Effect of assisted calving on uterine puerperal disorders occurrence, and on reproductive efficiency in crossbred dairy cows / Efeito do parto assistido na ocorrência de desordens uterinas puerperais e na eficiência reprodutiva de vacas leiteiras mestiças

The aim of this study was to evaluate the effect of the type of calving (normal or assisted) on the occurrence of puerperal uterine disorders and on the number of artificial inseminations (AI) per conception and pregnancy rate at 150 days postpartum (PPD). Cows were observed during parturition and the type of calving was classified as normal or assisted. Normal calving required no human interference, while assisted calving required a calf removal aid via vaginal access. There were 825 births, 7 stillbirths (0.85%) and 17 twins (2.06%). We analyzed 801 single births, from which 766 (95.63%) were normal and 35 (4.36%) assisted. Were evaluated the uterine disorders occurrence such as retained placenta combined with metritis (PR/ME) and clinical endometritis (CE). The overall occurrences were 10.24% (82/801) of RP/ME, 12.86% for CE and 5.12% for RP/ME and CE. Most of normal calving cows had healthy puerperium (73.89%), whereas a majority of assisted calving cows had uterine disorders (74.29%). The number of AI per conception was similar for cows that had either normal or assisted calving (2.39±0.08 and 3.00±0.43, P = 0.16). There was no evidence of negative influence of calving type on the 150 PPD pregnancy rate of lactating crossbreed dairy cows (P = 0.44). Healthy cows had higher 150 PPD pregnancy rate than cows affected by puerperium uterine disorders (51.65 vs. 42.92%). Normal calving crossbred dairy cows had a healthier puerperium, compared to cows with assisted calving which were more susceptible to puerperium uterine disorders. And cows with a health puerperium have a higher pregnancy rate at 150 days postpartum.

Objetivou-se avaliar em vacas leiteiras mestiças que pariram um bezerro vivo, o efeito do tipo de parto (normal ou assistido) na ocorrência de desordens uterinas puerperais e no número de inseminações artificiais (IA) por concepção e taxa de prenhez 150 dias pós-parto (DPP). As vacas foram monitoradas durante o parto e o tipo de parto foi classificado como normal ou assistido. O parto normal não precisou de interferência humana, enquanto o parto assistido precisou de auxílio para retirada do bezerro por via vaginal. Foram registrados 825 partos, sendo 7 natimortos (0,85%) e 17 gemelares (2,06%). Foram analisados 801 partos simples, dos quais 766 (95,63%) foram normais e 35 (4,36%) foram assistidos. Foram avaliadas a ocorrência de desordens uterinas como a retenção de placenta associada com metrite (RP/ME) e endometrite clínica (EC). A ocorrência das doenças foi de 10,24% (82/801) para RP/ME, 12,86% para EC e 5.12% para RP/ME com CE. A maioria das vacas com parto normal tiveram puerpério saudável (73,89%), enquanto a maioria das vacas com parto assistido apresentaram desordens uterinas (74,29%). O número de IA por concepção foi semelhante nas vacas que tiveram parto normal ou assistido (2,39±0,08 e 3,00±0,43, P = 0,16). Não houve evidência de influência negativa do tipo de parto na taxa de prenhez 150 DPP de vacas leiteiras mestiças em lactação (P = 0,44). Vacas saudáveis apresentaram maior taxa de prenhez 150 DPP do que vacas afetadas por desordens uterinas no puerpério (51,65 vs. 42,92%). Vacas leiteiras mestiças com parto normal tiveram um puerpério saudável, comparadas às que tiveram parto assistido, por sua vez foram mais susceptíveis as desordens uterinas no puerpério. E vacas com puerpério saudável resultaram em maiores taxas de prenhez aos 150 dias pós parto.

Cow milk or milk replacer in the diet of Holstein calves: effects on complete blood count, biochemistry variables, and performance / Leite de vacaousucedâneo do leitenadieta de bezerrosholandeses: efeitos no hemogramacompleto, variáveis ​​bioquímicas e desempenho

This study aimed to evaluate whether feeding calves with replacers instead of cow's milk interferes with complete blood count, biochemistry variables, survival, and weight gain, and the cost-benefit of these feeds in the suckling phase. We used 16 calves of the Holstein breed with an average of 8±4 days and 39±6 kg of average body weight, randomly divided into two groups: Replacer Group (N=8), receiving four liters of replacer milk during the 60 experimental days; and the Milk Group (N=8), calves receiving four liters of cow's milk. We observed that animals fed with cow's milk had higher body weight and weight gain at all weightings compared to those who consumed the dairy replacer. There was no calve death during the study. The cost (R$) of the diet of the calves that consumed replacer was lower. However, if we consider the weight gain during the experiment, the cost to produce 1 kg of body weight was similar between the treatments, because the calves that consumed milk were weaned with an average of 19kg more body weight. In conclusion, the use of dairy replacers as a replacer for cow's milk caused calves to have an overall lower performance compared to those who received cow's milk during the suckling phase.(AU)

Este estudo teve como objetivo avaliar se a alimentação de bezerros com sucedâneoem substituição ao leite de vaca causa interferência no hemograma, variáveis bioquímicas, sobrevivência e ganho de peso e o custo-benefício desses alimentos na fase de aleitamento. Foram utilizados 16 bezerros da raça Holandesa com média de 8±4 dias e 39±6 kg de peso corporal médio, divididos aleatoriamente em dois grupos: Grupo Sucedâneo (N=8), recebendo quatro litros de leite em pó durante os 60 dias de experimentos; e o Grupo Leite (N=8), bezerros recebendo quatro litros de leite de vaca. Observamos que os animais alimentados com leite de vaca apresentaram maior peso corporal e ganho de peso em todas as pesagens em relação aos que consumiram o sucedâneo lácteo. Não houve morte de bezerros durante o estudo. O custo (R$) da dieta dos bezerros que consumiram substituto foi menor. No entanto, se considerarmos o ganho de peso durante o experimento, o custo para produzir 1 kg de peso corporal foi semelhante entre os tratamentos, pois os bezerros que consumiram leite foram desmamados com média de 19kg a mais de peso corporal. Em conclusão, o uso de sucedâneos lácteos como substituto do leite de vaca fez com que os bezerros tivessem um desempenho geral inferior em comparação com aqueles que receberam leite de vaca durante a fase de aleitamento.(AU)

Risk factors related to the appearance of umbilical disorders in dairy calves / [Fatores de risco relacionados ao surgimento de afecções umbilicais em bezerros leiteiros]

The objective of this study was to determine the types of calve housing used in dairy farms, the prevalence of umbilical disorders and related risk factors. The 16 farms studied were visited to characterize the types of installation and possible risk factors, as well as information obtained from a questionnaire applied to the farmers. 806 Holstein calves were physically examined, in addition to collecting blood samples for the evaluation of Failures in Passive Immunity Transfer (FPIT), in animals that manifested inflammatory omphalopathies, and were also submitted to ultrasound examination. The prevalence of omphalopathies was assessed by Fisher's test, and multivariate logistic regression to assess risk factors. Eight types of installation were found: tropical house, suspended cage, collective stall, collective picket, Argentinean type, single-story cage, individual stall, and collective picket with chain. Omphalopathies accounted for 6.45% of the calves. Small size farms (up to 99 lactation cows) had high risk for umbilical disorders, ground floor collective calves, without side protection, with sand floor, in closed sheds and without heatstroke were considered risk factors for omphalopathies. Adequate colostrum and umbilical antisepsis are not associated with disease, its appearance being related to the housing conditions of the animals.(AU)

O objetivo deste estudo foi determinar os tipos de alojamento para bezerros leiteiros, a prevalência de onfalopatias e os fatores de risco relacionados. As 16 fazendas estudadas foram visitadas buscando-se caracterizar os tipos de instalação e os possíveis fatores de risco, além de informações obtidas de um questionário aplicado aos fazendeiros. Foram examinados fisicamente 806 bezerros da raça Holandesa, além da coleta de amostras de sangue, para avaliação da falha de transferência de imunidade passiva (FTIP), nos animais que manifestaram onfalopatias inflamatórias, sendo submetidos também ao exame ultrassonográfico. A prevalência das onfalopatias foi avaliada por teste de Fisher, e foi feita regressão logística multivariada a fim de se avaliarem os fatores de risco. Verificou-se oito tipos de instalação: casinha tropical, gaiola suspensa, baia coletiva, piquete coletivo, bezerreiro tipo argentino, gaiola térrea, baia individual e piquete coletivo com corrente. As onfalopatias corresponderam a 6,45% dos bezerros. Os bezerreiros coletivos térreos, sem proteções laterais, com piso de areia, borracha, concreto ou madeira, em galpões fechados, sem insolação, com alta densidade animal, antissepsia umbilical realizada por três dias e FTIP acima de 50% foram considerados fatores de risco para onfalopatias e possuem relação com o bezerreiro, sendo decisivas para evitar essas condições a colostragem e a antissepsia umbilical adequadas.(AU)

Effects on the lipid peroxidation and the antioxidant defense systems of the use of isoflurane or sevoflurane in calves undergoing surgery

Background: Incoming anaesthesia created by the use of many drugs with different physicochemical properties is a sourceof stress and trauma for the body. This event increases the oxidative response and changes the balance between oxidant/antioxidant capacity in the organism in favor of oxidant capacity. This situation is defined as oxidative stress. For thesereasons, studies are conducted to determine the effects of general anaesthetic agents on oxidant and antioxidant systems inthe organism. In this study, it was aimed to determine the effects of isoflurane and sevoflurane used for general anaesthesiain humans and animals on lipid peroxidation and antioxidant defense system in calves.Materials, Methods & Results: The study included 14 calves of different breeds, ages, sexes, and weighing, average 2 weeksold. The cases randomly were divided into 2 groups, the isoflurane group (group I), and the sevoflurane group (group II),and each group included 7 animals. Before general anaesthesia, 0.04 mg/kg atropine was administered intramuscularly toall animals for premedication. At 15 min after atropine administration, isoflurane was administered at an inspiratory concentration of 3-5% in group I, and sevoflurane was administered at an inspiratory concentration of 5-7% in group II, via aface mask for 15 min for the induction of anaesthesia. Endotracheal intubation was performed in all cases at the 15 min ofthe induction period following the onset of general anaesthesia symptoms. After the induction, anaesthesia was continuedat an inspiratory concentration of 1.5-3% in the isoflurane group and inspiratory concentration of 2.5-4% in the sevofluranegroup. Blood samples were taken just before anaesthesia, just before skin incision, at the end of anaesthesia and surgery,and at the 24 h postoperatively. The malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione...

Effects on the lipid peroxidation and the antioxidant defense systems of the use of isoflurane or sevoflurane in calves undergoing surgery

Background: Incoming anaesthesia created by the use of many drugs with different physicochemical properties is a sourceof stress and trauma for the body. This event increases the oxidative response and changes the balance between oxidant/antioxidant capacity in the organism in favor of oxidant capacity. This situation is defined as oxidative stress. For thesereasons, studies are conducted to determine the effects of general anaesthetic agents on oxidant and antioxidant systems inthe organism. In this study, it was aimed to determine the effects of isoflurane and sevoflurane used for general anaesthesiain humans and animals on lipid peroxidation and antioxidant defense system in calves.Materials, Methods & Results: The study included 14 calves of different breeds, ages, sexes, and weighing, average 2 weeksold. The cases randomly were divided into 2 groups, the isoflurane group (group I), and the sevoflurane group (group II),and each group included 7 animals. Before general anaesthesia, 0.04 mg/kg atropine was administered intramuscularly toall animals for premedication. At 15 min after atropine administration, isoflurane was administered at an inspiratory concentration of 3-5% in group I, and sevoflurane was administered at an inspiratory concentration of 5-7% in group II, via aface mask for 15 min for the induction of anaesthesia. Endotracheal intubation was performed in all cases at the 15 min ofthe induction period following the onset of general anaesthesia symptoms. After the induction, anaesthesia was continuedat an inspiratory concentration of 1.5-3% in the isoflurane group and inspiratory concentration of 2.5-4% in the sevofluranegroup. Blood samples were taken just before anaesthesia, just before skin incision, at the end of anaesthesia and surgery,and at the 24 h postoperatively. The malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione...(AU)

Comparison of use of isoflurane or sevoflurane for anaesthesia induced by mask in calves

Background: Inhalation anaesthesia is an effective and reliable general anaesthesia method for inactivity, analgesia, and unconsciousness in extensive surgical procedures. Although widely used, especially in small animals, there are very few studies investigated the reliability and superiority of inhalation anaesthesia in surgical procedures for ruminants. This study intended to evaluate the anaesthetic effects of isoflurane and sevoflurane in different surgical cases with endotracheal intubation following the induction of anaesthesia using a calve-specific facemask, which is not yet a routine option in cattle. Materials, Methods & Results: The study was conducted on 14 calves, from new-born up to 3 months-old, that undergoing various surgical operations. The animals were divided into isoflurane and sevoflurane groups, and each group contained 7 animals. In all cases, atropine (0.04 mg/kg was administered intramusculer as premedication before 15 min from anaesthesia induction. For induction, the anaesthetic agent was given at an inspiratory concentration of 3-5% in the isoflurane group and at an inspiratory concentration of 5 - 7% in the sevoflurane group during 5 min via mask at 15 min after atropine administration. In both groups, endotracheal intubation was performed (about 1-3 min) after of general anaesthesia symptoms starting. At 5 min after induction, anaesthesia was continued at 1.5 - 3% in the isoflurane group and at 2.5 - 4% in the sevoflurane group during operation. The animals were monitored during anaesthesia and, anaesthetic effect, reaction of the calve, pronounced side effects, Heart Rate (HR), Systolic Arterial Blood Pressure (SABP), Diastolic Arterial Blood Pressure (DABP), Mean Arterial Blood Pressure (MABP), Respiration Rate (RR), Pulse Rate (PR), Arterial Oxygen Saturation (SpO2 ) were recorded at before anaesthesia, the premedication period, 5...

Necrose asséptica da cabeça do fêmur em cão da raça spitz alemão: Relato de caso

A necrose asséptica da cabeça do fêmur pode ser conhecida também como doença de Legg-Calvé-Perthes, osteocondrite dissecante, necrose avascular da cabeça do fêmur, dentre outras. É uma afecção não inflamatória da cabeça e colo femoral que ocorre principalmente em animais jovens e de pequeno porte. Os sinais clínicos costumam ser parecidos com as de outras enfermidades ortopédicas por isso é imprescindível um minucioso exame clínico e físico do animal, juntamente com exame de imagem para auxiliar no diagnóstico. A escolha do tratamento a ser utilizado depende da severidade da doença podendo ser conservador ou cirúrgico.(AU)

Aseptic necrosis of the femoral head may also be known as Legg-Calvé-Perthes disease, osteochondritis dissecans, avascular necrosis of the femoral head, among others. It is a noninflammatory condition of the femoral head and neck that occurs mainly in young and small animals. The clinical signs are usually similar to those of other orthopedic diseases, so a thorough clinical and physical examination of the animal is essential, along with imaging to aid in diagnosis. The choice of treatment to be used depends on the severity of the disease and may be conservative or surgical.(AU)

Necrose asséptica da cabeça do fêmur em cão da raça spitz alemão: Relato de caso

A necrose asséptica da cabeça do fêmur pode ser conhecida também como doença de Legg-Calvé-Perthes, osteocondrite dissecante, necrose avascular da cabeça do fêmur, dentre outras. É uma afecção não inflamatória da cabeça e colo femoral que ocorre principalmente em animais jovens e de pequeno porte. Os sinais clínicos costumam ser parecidos com as de outras enfermidades ortopédicas por isso é imprescindível um minucioso exame clínico e físico do animal, juntamente com exame de imagem para auxiliar no diagnóstico. A escolha do tratamento a ser utilizado depende da severidade da doença podendo ser conservador ou cirúrgico.

Aseptic necrosis of the femoral head may also be known as Legg-Calvé-Perthes disease, osteochondritis dissecans, avascular necrosis of the femoral head, among others. It is a noninflammatory condition of the femoral head and neck that occurs mainly in young and small animals. The clinical signs are usually similar to those of other orthopedic diseases, so a thorough clinical and physical examination of the animal is essential, along with imaging to aid in diagnosis. The choice of treatment to be used depends on the severity of the disease and may be conservative or surgical.

Effects of flunixin meglumine on oxidant and antioxidant system after disbudding with caustic paste in calves

Background: Disbudding is often practiced in modern farm because of the reasons for the safekeeping of the animal, other animals lessen the risk of injury and less aggressive behavior. Without regard to the method of disbudding leads to disruption behavioral changes, cardiac and endocrine responses related pain of animals. Sedation, local anesthesia and analgesia are performed studies in order to eliminate of cardiac, endocrine, behavioral response which is caused by pain associated with disbudding. In this study, it was aimed to determine the effect on the oxidant and antioxidant system in the calves of disbudding by using the caustic paste with and without painkiller.Materials, Methods & Results: The animal material of the study was created 24 Simmentals calves in different sexes on average 2 weeks (± 2 days) and 50 kg (± 15 kg) live weight. The cases were randomly divided into 2 groups of 12 calves in each group. In the group I (analgesia group); caustic paste+painkiller (2.2 mg-1 flunixin meglumine intravenous, IV) and group II (non-analgesia group); as disbudding applied with caustic pasta application only were divided into 2 groups. In the I group, 15th min before the application, flunixin meglumine at a dose of 2.2 mg-1 was administered IV and the horn blunting was performed by caustic paste method. Blood samples were taken at 15, 30 and 60th min after completion of horn blunting and physiological findings were recorded. In group II, the horns of the calves were disbudding with the same technique (but no analgesia aplication). Blood samples were taken at 15, 30 and 60th min after completion of horn blunting and physiological findings were record. Cortisol, glucose, total oxidant capacity (TOC) and total antioxidant capacity (TAC), 8-hydroxy-2’-deoxyguanosine (8-OHdG), glutathione (GSH), superoxide dismutase (SOD) enzymes measurements (ELISA) were performed in both groups.[...]

Effects of flunixin meglumine on oxidant and antioxidant system after disbudding with caustic paste in calves

Background: Disbudding is often practiced in modern farm because of the reasons for the safekeeping of the animal, other animals lessen the risk of injury and less aggressive behavior. Without regard to the method of disbudding leads to disruption behavioral changes, cardiac and endocrine responses related pain of animals. Sedation, local anesthesia and analgesia are performed studies in order to eliminate of cardiac, endocrine, behavioral response which is caused by pain associated with disbudding. In this study, it was aimed to determine the effect on the oxidant and antioxidant system in the calves of disbudding by using the caustic paste with and without painkiller.Materials, Methods & Results: The animal material of the study was created 24 Simmentals calves in different sexes on average 2 weeks (± 2 days) and 50 kg (± 15 kg) live weight. The cases were randomly divided into 2 groups of 12 calves in each group. In the group I (analgesia group); caustic paste+painkiller (2.2 mg-1 flunixin meglumine intravenous, IV) and group II (non-analgesia group); as disbudding applied with caustic pasta application only were divided into 2 groups. In the I group, 15th min before the application, flunixin meglumine at a dose of 2.2 mg-1 was administered IV and the horn blunting was performed by caustic paste method. Blood samples were taken at 15, 30 and 60th min after completion of horn blunting and physiological findings were recorded. In group II, the horns of the calves were disbudding with the same technique (but no analgesia aplication). Blood samples were taken at 15, 30 and 60th min after completion of horn blunting and physiological findings were record. Cortisol, glucose, total oxidant capacity (TOC) and total antioxidant capacity (TAC), 8-hydroxy-2-deoxyguanosine (8-OHdG), glutathione (GSH), superoxide dismutase (SOD) enzymes measurements (ELISA) were performed in both groups.[...](AU)

Caracterização da dinâmica folicular no pós-parto de vacas da raça Gir amamentando, criadas em regime de pastagem tropical

Este estudo teve como objetivo avaliar a dinâmica folicular de vacas da raça Gir no período pós-parto. Foram utilizadas 15 vacas recém-paridas amamentando, mantidas a pasto e recebendo água e mineralização à vontade. Os animais foram pesados semanalmente a partir do parto até a quinta semana pós-parto (medidas do PV Parto a PV5), além de ser avaliado o escore de condição corporal (ECC) da primeira semana à sexta semana pós-parto (ECC1 a ECC5). Durante todo o período experimental os animais foram monitorados visualmente, duas vezes ao dia, para possível manifestação de estro pós-parto. A involução uterina foi avaliada macroscopicamente por palpação transretal, classificando o posicionamento dos cornos uterinos. O estudo da dinâmica folicular ovariana pós-parto foi realizado por meio de ultrassonografia do quarto (4PP) ao quadragésimo dia pós-parto (40PP). Foram realizadas medições diárias registrando-se os diâmetros (mm) máximos do maior e segundo maior folículos presentes em cada ovário. As vacas foram divididas em três grupos experimentais: G1: vacas que apresentaram crescimentos foliculares esporádicos em intervalos irregulares, sem aparente perfil característico de ondas folicularese seus maiores folículos não ultrapassando diâmetros de 7mm (n=5); G2: vacas que apresentaram crescimentos foliculares regulares, com perfil característico de ondas foliculares e subordinação e com os seus maiores folículos de cada onda atingindo diâmetros de, no máximo, de 8 a 10mm (n=5); G3: vacas que apresentaram crescimentos foliculares regulares, com perfil característico de ondas foliculares e subordinação, tendo os seus maiores folículos de cada onda atingindo, pelo menos em uma onda folicular, diâmetros superiores a 10mm (n=5). Observou-se perda de peso (P<005) dos animaisdo G1, sendo o peso vivo no PV6 representando perda de 17% em relação ao PV Parto. Houve diminuição de ECC significativa nos animais dos grupos G1 e G2 no ECC6, em relação ao ECC1. O posicionamento uterino se tornou pélvico nos três grupos a partir de 17 dias pós-parto. Os animais dos grupos G2 e G3 tiveram maior número de ondas durante os 40 dias de avaliação e maior diâmetro de folículo no 4PP. Características da dinâmica folicular, diâmetro máximo do maior folículo (mm), comprimento de onda folicular (dias), duração do crescimento (dias), taxa de crescimento (mm/dia), persistência folicular (dias) e diâmetro do segundo maior folículo (mm) foram diferentes nos animais dos três grupos, sendo valores maiores para os animais do grupo G3, intermediários para G2 e menores para G1.

This study aimed to evaluate the follicular dynamics of Gir cows in the post partum period. Fifteen recently calved cows were used, which were breast feeding, kepton pasture, receiving water and mineralization. The animals were weekly weighed from the calve moment until the fifth week post partum, besides it was assessed the body condition score (ECC) from the first week to the sixt week post partum. During the experimental period, the animals were visually monitored twice a day for possible manifestation of post partum estrus. The uterine involution of the cows was evaluated macroscopically by transrectal palpation, classifying the position of the uterine horns. The study of post partum ovarian folicular dynamics was performed by ultrasonography from the fourth day (4PP) to the fortieth day post partum. Daily scores were done by recording the maximum diameters (mm) of the largest follicles and the second largest follicles presente in each ovary. The cows were divided in three groups: G1: five cows showed sporadic folicular grow that irregular intervals, with no apparent characteristic profile of folicular waves and their largest follicles not exceeded 7mm in diameter; G2: five cows showed regular folicular growth, folicular waves characteristic profile and the largest follicles reached between 8 to 10mm; G3: five cows showed regular folicular growth, folicular waves characteristic profile and the largest follicles reached, at least in one, more than 10mm. Significant weight loss was observed in G1, representing 17% of loss between PV 6 and PV Parto. Significant decrease in ECC of G1 animals and ECC6 of G2 animals in inrelation to ECC1. The uterine position became pelvic in the three groups after 17 days post partum. G2 and G3 had a greater number of waves during the 40 days of evaluation and a larger follicle diameter in the 4PP. Folicular dynamics features, such as maximum diameter of the largest follicle (mm), folicular wave (days), growth duration (days), growth rate (mm/day), folicular persistence (days), diameter of these conflargest follicle (mm) were higher in G3, intermediate for G2 and lower for G1.

Aspectos clínicos e imunológicos relacionados à infecção pelo Vírus da Leucose Enzoótica Bovina (VLB), em novilhas no período de transição

O objetivo da pesquisa foi avaliar o impacto do Vírus da Leucemia Bovina (Bovine Leukemia Virus - BLV) sobre o perfil hematológico, bioquímico, inflamatório e do metabolismo energético em novilhas leiteiras naturalmente infectadas no período de transição. O rebanho foi inicialmente triado por meio da prevalência de anticorpos específicos anti-BLV pela técnica de ensaio imunoenzimático (ELISA). Para tanto, 24 novilhas prenhas das raças Holandesa e Jersey foram distribuídas em 2 grupos experimentais, composto por novilhas soropositivas BLV +, (n=12); e o grupo BLV composto por novilhas soronegativas (n=12). Foi realizada ainda a pesquisa de DNA proviral por avaliação digital da reação da polimerase em cadeia (ddrPCR). Amostras de sangue foram colhidas semanalmente nos períodos -3, -2, -1, parto, +1, +2 e +3 semanas em relação ao parto previsto, e avaliadas para determinação de perfil hematológico, bioquímico hepático (AST, GGT) Inflamatório (Fibrinogênio, HP) e energético (BHB, triglicerídeos e colesterol). Os animais foram monitorados diariamente por um sistema automático de avaliação de ruminação. Foram levantados os registros relativos à saúde, produção e qualidade do leite das novilhas.. De forma complementar, os animais foram ainda distribuídos em grupos com alta carga proviral e baixa carga proviral, para avaliação dos mesmos parâmetros previamente descritos. Para análise estatística, os dados foram linearizados e avaliados pelo modelo linear misto (Mixed model). O método de regressão logística foi usado para avaliação de inflamação, cetose e lesão hepática. A prevalência encontrada para anticorpos anti- BLV foi de 57.25% (351/613), sendo nas novilhas prenhes de 38.7% (76/124). A infecção por BLV alterou o perfil hematológico das novilhas para CHCM (P= 0.026), bioquímico com a elevação nas concentrações da enzima AST (P= 0.023), além de alterar o perfil cinético dos triglicerídeos entre os grupos (P= 0.023). A avaliação do perfil inflamatório revelou uma influência da infecção por BLV no fibrinogênio (P= 0.043), e aumento expressivo no risco de elevação da HP (OR= 4.959). Adicionalmente, as contagens leucocitárias de animais com alta carga viral foram significativamente maiores no grupo com alta carga vira (P= 0.018), especialmente por linfocitose (P= 0.036). Conclui-se que a infecção pelo BLV pode alterar o perfil hematológico e bioquímico e o metabolismo energético de novilhas no período de transição; além de aumentar as chances de inflamação. A carga viral pode impactar nas contagens leucocitárias, especialmente por predisposição de linfocitose.

The aim of the study is to evaluate the impact of the Bovine Leukemia Virus (BLV) on hematological, biochemical, inflammatory and energetic metabolic profile, in naturally infected heifers during the transition period. Initially, herd was screened (n= 613) to determinate anti-BLV specific antibodies by using immunenzymatic assay (ELISA). Therefore, 24 pregnancy Holstein and Jersey heifers were divided in two experimental groups composed by seropositive BLV+ (12); and seronegative BLV- (12) heifers. Proviral DNA was also evaluated through the Droplet digital Polimerase chain reaction (ddPCR). Whole blood and serum were weekly sampled in interval -3, -2, -1, 0, calve, +1, +2, +3 weeks, and evaluated to determination of hematological, hepatic biochemistry (AST and GGT), Inflammatory (Fibrinogen, Haptoglobin), and energetic (BHB, triglycerides and cholesterol). Animals were daily monitored with automatic rumination monitoring system, and clinically by the farm veterinaries assistance. Complementarily. Complementarily, animals were also divided in groups with high and low proviral load, to evaluation of the same parameters previously described. For the statistical analyses, data were linearized and evaluated according to Mixed Model. Regression logistic model were used to evaluate inflammation, ketosis and hepatic damage. Herd antibodies prevalence was 57.25% (351/613), with heifers prevalence of 38.7% (76/124). BLV infection altered heifers hematological profile for MCHC (P= 0.026), Biochemical by increasing AST concentration (P= 0.023), and altered the triglycerides kinetic amog groups (P= 0.023). Inflamatory profile evaluation revels an influence of BLV infection on fibrinogen (P= 0.043), and an expressive increase risk for HP elevation (OR= 4.959) in BLV+ animals. Moreover, leukocytes count were significantly increased in group with high proviral load (P= 0.018), mainly by lymphocytosis (P= 0.036). In conclusion, BLV infection altered the hematological, biochemnical and energetic metabolic profile of heifers during the transition period. Moreover, proviral load may increase leukocytes count especially due to lymphocytosis.

Uso de diferentes gonadotrofinas na maturação in vitro de oócitos ovinos

O objetivo deste estudo foi avaliar o efeito do uso das gonadotrofinas eCG e hCG, comparado ao FSH, na maturação in vitro de oócitos ovinos. Para tanto, ovários ovinos foram transportados do matadouro local para o laboratório, em solução salina, a 0,9%, a 30°C, até duas horas após o abate. Após a colheita, os oócitos foram avaliados e divididos em três grupos: grupo CON, onde os oócitos foram imersos em meio MIV base: TCM-199, suplementado com EGF (20 ng/mL), cisteamina (100 L/mL); E2 (1 g/mL); L glutamina (1 mM), Piruvato (40 mM); Soro Fetal Bovino (10%v/v); nos grupos ECG e HCG, os oócitos foram imersos em meio MIV base, adicionado, respectivamente, de 10 UI/mL de eCG e de 10 UI/mL de hCG; já no grupo FSH, os oócitos foram imersos em meio MIV base, adicionado de 10 g/mL de FSH-p. A MIV dos oócitos foi realizada a 38,5°C em atmosfera umidificada de 5% de CO2 em ar, durante 24 horas. Não foram observadas diferenças significativas com relação à taxa de expansão de células do cumulus. Todavia, ao se comparar os grupos dentro de cada grau de expansão, no grupo FSH, foi obtido o maior percentual de oócitos com expansão total de células do cumulus (P<0,05). Já o grupo eCG foi superior para expansão moderada (P<0,05), enquanto o grupo HCG foi superior para expansão leve (P<0,05). A percentagem de oócitos em MII foi maior no grupo ECG do que no grupo CON e HCG (P<0,05), mas foi semelhante ao grupo FSH. Em conclusão, 10 UI de eCG podem ser utilizadas em substituição ao FSH na MIV de oócitos ovinos.

The aim of this study was to evaluate the effect of using gonadotropins eCG and hCG, compared to FSH, on in vitro maturation of sheep oocytes. To this end, sheep ovaries were transported from the local slaughterhouse to the laboratory in 0.9% saline at 30 °C within two hours of slaughter. After harvest, the oocytes were evaluated and allocated into three groups: CON group, where the oocytes were immersed in IVM base medium: TCM-199, supplemented with EGF (20 ng / mL), cysteamine (100 L / mL); E2 (1 g / mL); L - glutamine (1 mM), Pyruvate (40 mM); Fetal Calve Serum (10% v / v); in the ECG and HCG groups, the oocytes were immersed in IVM base medium, added, respectively, 10 IU / mL eCG and 10 IU / mL hCG; In the FSH group, the oocytes were immersed in IVM base medium, added with 10 g / mL pFSH. The IVM was performed at 38.5 °C, in a humidified atmosphere of 5% CO2 in air, for 24 hours. No significant differences were observed with respect to cumulus cell expansion rate. However, when comparing the groups within each degree of expansion, in the FSH group, the highest percentage of oocytes with total cumulus cell expansion was obtained (P<0.05). The eCG group was superior for moderate expansion (P<0.05), while the HCG group was superior for mild expansion (P<0.05). The percentage of oocytes in MII was higher in the ECG group than in the CON and HCG groups (P <0.05), but was similar to the FSH group. In conclusion, 10 IU eCG can be used in place of FSH in sheep oocyte IVM.

Efeito de diferentes biotécnicas reprodutivas (IA, TE e FIV) no desempenho produtivo e reprodutivo de fêmeas da raça Holandesa

Resumo: Biotécnicas da reprodução como IA, TE-in vivo e TE-in vitro têm sido aplicadas como estratégias de manejo visando maior produtividade, ganho genético e eficiência reprodutiva na pecuária brasileira e mundial. O objetivo deste estudo foi avaliar o efeito das diferentes biotécnicas (IA, TE-in vivo e TE-in vitro) no desempenho reprodutivo de vacas da raça Holandesa em lactação, e avaliar o desempenho reprodutivo e produtivo de sua progênie. O estudo foi conduzido na Fazenda Santa Rita/Agrindus S.A. localizada em Descalvado, SP, Brasil. Foram analisadas as seguintes variáveis em vacas Holandesas lactantes que receberam as três biotecnologias contemporaneamente nos anos de 2013 a 2018: taxa de gestação aos 30 (TG30) e 60 (TG60) dias, taxa de perda gestacional entre 30 e 60 dias (TPG) e taxa de aborto (TA). Além disso, também foram analisadas as variáveis duração da gestação (DG), facilidade de parto (FP) e retenção de anexos fetais (RAF). Na progênie, foram avaliadas as seguintes variáveis: informação genômica (IG), peso ao nascimento (PN) e ao desmame (PD), mortalidade do nascimento ao desmame (MN-D) e idade à primeira cobertura (IP-COB), das bezerras nascidas entre os anos de 2013 a 2018. Ainda, foram avaliadas idade ao primeiro parto (IP-PAR) e a produção de leite total na primeira lactação (PLT-1), das bezerras nascidas entre os anos de 2013 a 2017, e a produção de leite total na segunda lactação (PLT-2), das bezerras nascidas entre os anos de 2013 a 2015. Os dados foram analisados por procedimentos do SAS. Houve interação biotécnica ano para as variáveis TG30 (P<0,0001), TG60 (P<0,0001) e TPG (P=0,03), porém, houve efeito de biotécnica (P=0,01) e de ano (P=0,03) para TA. Houve interação biotécnica ano para DG (P<0,0001). Houve efeito de biotécnica para FP (P<0,0001) e não houve efeito de biotécnica para RAF (P=0,14). Houve interação biotécnica ano para IG (P<0,0001). Não houve interação biotécnica ano (P=0,30), efeito de biotécnica (P=0,62) e de ano (P=0,82) para MN-D. Houve interação biotécnica ano para PN (P=0,01) e PD (P<0,0001). Entretanto, houve apenas efeito de ano para IP-COB (P<0,0001), IP-PAR (P=0,0002) e PLT-1 (P<0,0001). Não houve interação biotécnica ano (P=0,41), efeito de biotécnica (P=0,97) e de ano (P=0,92) para PLT-2. Nas progenitoras, a TE apresentou maior eficiência reprodutiva, com semelhantes perdas gestacionais quando comparada com a IA. Adicionalmente, a TE-in vivo apresentou semelhantes eficiência reprodutiva e perda gestacional do que a TE-in vitro. Na progênie, não houve efeito de biotecnologia na produtividade de fêmeas nascidas de IA, TE-in vivo e TE-in vitro.

Abstract: Reproductive biotechnologies as AI, ET-in vivo and ET-in vitro have been applied as manegement strategies to acomplish productivity, genetic gain and reproductive efficiency on Brazilian and worldwide livestock. However, there are differences on the efficiency of this biotechnologies that may compromises the reproductive and productive development of the farms. The objective of this study was to evaluate the effect of different reproductive technologies (AI, ET-in vivo and ET-in vitro) on reproductive development of lactating Holstein cows, and evaluate the reproductive and productive development of their progeny. The study was conducted at Santa Rita/Agrindus S.A. Farm, located in Descalvado, SP, Brazil. The following variables of the lactating Holstein cows that received the three biotechnologies contemporaneously from 2013 to 2018 were analyzed: gestation rate at 30 (GR30) and 60 (GR60) days, gestation lost between 30 and 60 days (GLO) and abortion rate (AR). Additionally, other variables were analyzed: gestation length (GLE), labor facility (LF) and retention of fetal attachments (RFA). The following variables were analyzed on the progeny: genomic information (GI), weight at birth (WB) and at weaning (WW), mortality from calve to weaning (MCW) and age at first conception (ACON) of calves born from 2013 to 2018. Also, were analyzed age at first calve (ACA) and milk production from the first lactation (MP1) of calves born from 2013 to 2017, and milk production from the second lactation (MP2) of calves born from 2013 to 2015. The data were analyzed by procedures of SAS. There was interaction biotechnology year to GR30 (P<0,0001), GR60 (P<0,0001) and GLO (P=0,03), however, there was effect of biotechnology (P=0,01) and effect of year (P=0,03) to AR. There was interaction biotechnology year to GLE (P<0,0001). There was effect of biotechnology to LF (P<0,0001), without effect of biotechnology to RFA (P=0,14). There was interaction biotechnology year to GI (P<0,0001). There was no interaction biotechnology year (P=0,30), effect of biotechnology (P=0,62) and effect of year (P=0,82) to MCW. There was interaction biotechnology year to WB (P=0,01) and WW (P<0,0001). However, there was only effect of year to ACON (P<0,0001), ACA (P=0,0002) and MP1 (P<0,0001). There was no interaction biotechnology year (P=0,41), effect of biotechnology (P=0,97) and effect of year (P=0,92) to MP2. On lactating cows ET presented better reproductive efficiency, with similar gestation lost than AI. Additionally, ET-in vivo presented similar reproductive efficiency and lower gestation lost than ET-in vitro. On progeny, there were no differences between productivity of females born from AI, ET-in vivo or ET-in vitro.

HORMÔNIO ANTI-MULLERIANO E DESEMPENHO NA PRODUÇÃO IN VITRO DE EMBRIÕES EM FÊMEAS DA RAÇA GIR (Bos indicus)

O hormônio anti-mülleriano (AMH) tem sido proposto como critério para otimizar a PIVE (Produção In Vitro de Embriões) em bovinos. Contudo, não há parâmetros claros para o uso do AMH como critério para a seleção de doadoras de oócitos. Dessa forma, o objetivo deste estudo foi avaliar a concentração plasmática de AMH como potencial marcador para a seleção de fêmeas com maior eficiência na PIVE. Novilhas pré-púberes (n=120) foram submetidas à contagem folicular antral (CFA) e à coleta de sangue para análise de AMH. As associações entre AMH e CFA, resultados de PIVE (n=506) e valor genômico, foram estimadas. A concentração plasmática de AMH foi analisada, usando-se a curva característica de operação do receptor (ROC). Em seguida, verificou-se o valor de corte que resultaria em um aumento na média para a produção de oócitos totais, viáveis e embriões. Por fim, utilizaram-se dados de PIVE de doadoras (n=658) com valores genômicos conhecidos para a produção de leite (GPTAm) e idade ao primeiro parto (GPTAafc) para determinar a associação entre os valores genômicos e os indicadores de sucesso na PIVE. Em média, as novilhas apresentaram CFA de 31,2 ± 1,1 e AMH de 932,9 ± 48,4 ng/mL e produziram 32,3 ± 1,5 oócitos totais, 25,9 ± 1,4 oócitos viáveis e 5,3 ± 0,4 embriões por sessão OPU-PIVE. Observou-se correlação positiva e moderada entre AMH e CFA, oócitos totais, oócitos viáveis e embriões produzidos, mas não com GPTAm ou GPTAafc. A área sob a curva ROC (AUC) para oócitos totais, oócitos viáveis e embriões produzidos foi de 0,77 (P<0,0001), 0,75 (P <0,0001) e 0,72 (P = 0,0003), e os pontos de corte estimados para a concentração de AMH foram 761,4, 622,5 e 681,5 pg/mL, respectivamente. Após exclusões de doadores com valores de AMH menores, as médias foram maiores (P <0,05) em um valor de corte de 632,4 pg/mL para oócitos totais, 672,3 pg/mL para oócitos viáveis e 776,8 pg/mL para embriões produzidos. Portanto, a concentração de AMH pode ser usada como marcador para selecionar doadoras com maior produção de oócitos e embriões e, assim, aumentar os resultados de PIVE em novilhas Gir. A seleção de doadoras Gir com base no rendimento de oócitos pode resultar em um aumento baixo, mas positivo, no GPTAm do rebanho. Entretanto, não apresenta relação com a idade ao primeiro parto

The anti-Mullerian hormone (AMH) has been proposed as a criterion to optimize IVEP (In Vitro Embryo Production) in cattle. However, there are no clear parameters for the use of AMH as a criterion for the selection of oocyte donors. Thus, the aim of this study was to evaluate the plasma concentration of AMH as a potential marker for the selection of females with greater efficiency in IVEP. Pre-pubertal heifers (n = 120) were submitted to blood collection for AMH analysis and antral follicle count (AFC). The associations between AMH and AFC, IVEP results (n = 506) and genomic value were estimated. The plasma AMH concentration was analyzed using the receiver operating characteristic curve (ROC). Then, the cutoff value that would result in an increase in the average for the production of total, viable oocytes and embryos was verified. Finally, IVEP data from donors (n = 658) with known genomic values for milk production (GPTAm) and age at first calve (GPTAafc) were used to determine the association between genomic values and success indicators in IVEP. On average, heifers presented AFC of 31.2 ± 1.1 and AMH of 932.9 ± 48.4 ng / mL and produced 32.3 ± 1.5 total oocytes, 25.9 ± 1.4 viable oocytes and 5.3 ± 0.4 embryos per OPU-IVEP session. A positive and moderate correlation was observed between AMH and AFC, total oocytes, viable oocytes and produced embryos, but not with GPTAm or GPTAafc. The area under the ROC curve (AUC) for total oocytes, viable oocytes and embryos produced was 0.77 (P <0.0001), 0.75 (P <0.0001) and 0.72 (P = 0, 0003), and the cutoff velues estimated for the AMH concentration were 761.4, 622.5 and 681.5 pg / mL, respectively. After exclusions from donors with lower AMH values, the averages were higher (P <0.05) at a cutoff value of 632.4 pg / mL for total oocytes, 672.3 pg / mL for viable oocytes and 776.8 pg / mL for produced embryos. Therefore, the concentration of AMH can be used as a marker to select donors with higher production of oocytes and embryos and, thus, increase the results of IVEP in Gir heifers. Selection of Gir donors based on oocyte yield may result in a low, but positive, increase in herd GPTAm. However, it is not related to age at first delivery

MICROBIOTA FECAL DE BEZERROS LACTENTES: EFEITO DA IDADE, DA RAÇA E DA DIARREIA

Os animais vivem em simbiose com microrganismos, as bacterias exercem várias funções importantes no organismo como digestão de alimentos, desenvolvimento do sistema imune e resistência à patógenos. Agentes infecciosos podem provocar desequilíbrios da microbiota e desenvolver doenças no hospedeiro. Com o objetivo de estudar os efeitos que alteram a microbiota intestinal dos bezerros lactentes, dois estudos foram desenvolvidos. O primeiro, investigou o efeito da idade e genética na microbiota intestinal de bezerros Nelore (n= 10) e Cruzados (Nelore x Raça britânica; n= 10) mantidos a campo com suas mães, sem receber suplementação. Foram realizadas oito colheitas nos respectivos dias de vida, 5 (5d), 14d, 28d, 60d, 90d, 180d, no desmame (245d) e quinze dias após (260d), e foram colhidas amostras de seis vacas (DAM) no desmame para servir como controle. O efeito do peso ao desmame nas populações bacterianas entre Nelore e Cruzados foi avaliado. As regiões V3-V4 do gene 16S rRNA foram sequenciadas (Illumina). No geral, os filos mais abundantes foram Firmicutes (64.68%), Bacteroidetes (16.81%), Fusobacteria (9.10%), Proteobacteria (1.49%) e Actinobacteria (1.28%). A riqueza aumentou de acordo com o crescimento dos bezerros até se tornar similar à da mãe ao desmame. A composição e a estrutura da microbiota intestinal mudaram com a idade. Não há semelhança na composição da microbiota entre bezerros e as mães, mas a estrutura da microbiota foi semelhante à da mãe próximo ao desmame. O grupo genético demonstrou influenciar a composição aos 60d e 90d e a estrutura aos 60d, 90d, 245d e 260d. O gênero Fusobacterium foi abundante na microbiota dos bezerros de corte saudáveis. Os bezerros Cruzados foram mais pesados do que os Nelore ao desmame (240,70 vs. 216,80 kg). O segundo estudo, teve como objetivos avaliar a eliminação de Cryptosporidium durante o primeiro mês de vida de bezerras leiteiras e as mudanças na microbiota intestinal. Foram colhidas amostras de fezes de 30 bezerras durante o primeiro mês de vida, foram anotados dados de colostro, transferência de imunidade passiva, uso de antibióticos e diagnóstico de doenças. A presença do Cryptosporidium foi detectada com SNPCR em 15 amostras de cada bezerra em dias alternados, totalizando 450 amostras. Amostras de 16 bezerras foram utilizadas para a análise da microbiota intestinal de acordo com o primeiro dia de diarreia (D0), anterior a diarreia (D-4 e D-2), durante o curso da diarreia (D+4), ao final (DX) e seis dias após (DX+6). Amostras do segundo dia de vida (n=30), terceiro (n=12) e quarto dia (n=18) também foram analisadas. A região V4 do gene 16S rRNA foi sequenciada (Illumina). Foi observada ocorrência de diarreia em todas as bezerras, com início no quinto dia de vida e duração média de 7,86 dias. Todas as bezerras foram positivas para Cryptosporidium. Os principais filos observados foram Firmicutes, Proteobacteria, Fusobacteria, Bacteroidetes e Actinobacteria. O Cryptosporidium spp. alterou a microbiota intestinal e o filo Fusobacteria aumentou durante a diarreia. A efetiva transferência de imunidade passiva diminuiu o uso de antibióticos e foi observado que o colostro e a imunidade têm funções na restauração da microbiota dos animais e necessitam de maiores estudos.

Animals and microorganisms live in symbiosis, bacteria are responsible by many important functions in the body like degradation of food, development of immune system and resistance against pathogens. Infectious agents can cause microbial dysbiosis and develop disease in the host. In order to study the effects that change the intestinal microbiota of nursing calves, two studies were developed. The first one exploited the effect of age and genetic of fecal microbial communities from beef calves rearing at range, twenty calves from two breed group, 100% Nellore pure breed (n= 10) and Crossbreed (50% Nellore x 50% Britannic breed; n= 10), were maintenance at range with dams without supplementation. Fecal samples were collected on days of life, 5 (5d), 14d, 28d, 60d, 90d, 180d, at weaning (245d) and after 15 days (260d) and of six dams (DAM) at weaning to be used as control. In addition, the effect of weight at weaning on bacterial taxa between Nellore straightbred and crossbred were evaluated. The sequencing was performed in Illumina system of V3-V4 regions of 16S rRNA gene. The phylum most abundant during all trial were Firmicutes (64.68%), Bacteroidetes (16.81%), (Fusobacteria (9.10%), Proteobacteria (1.49%) and Actinobacteria (1.28%). Richness increase as calves growth until be similar to DAM near of weaning. Membership and Structure changes over ages, there was no similarities of membership between calves and DAM, but the structure was similar to DAM around of weaning. Genetic group showed differences for membership at 60d and 90d and for structure at 60d, 90d, 245d and 260d. The Fusobacterium genus was abundant in fecal microbiota of healthy calves. The Crossbreed calves were heavier than Nellore at weaning (240.70 vs. 216.80 kg). The second study, the objective was evaluated the Cryptosporidium shedding during the first month of life and the effect of diarrhea in the intestinal microbiota of dairy calves. Fecal samples from 30 calves were collected during the first month of life, records of colostrum, passive immunity transference, antibiotics use and diseases. Cryptosporidium shedding was evaluated by SN-PCR in 15 samples from each calve every other day, totalizing 450 samples. Samples of sixteen calves were choose for intestinal microbial analysis of 16S rRNA gene, accord first day of diarrhea (D0), prior to diarrhea (D-4 and D-2), during diarrhea course (D+4), at finish of diarrhea (DX) and after six days (DX+6). Additionally, samples from second (n=30), third (n=12) and fourth (n=18) day of life were analyzed too. The v4 gene was sequenced with use of Illumina. Diarrhea was observed in all calves (100%), starting at day 5 of life and an average of 7.86 days. All calves were positive for Cryptosporidium spp. The main phyla observed were Firmicutes, Proteobacteria, Fusobacteria, Bacteroidetes and Actinobacteria. The Cryptosporidium spp. change the intestinal microbiota and Fusobacteria phylum increase with diarrhea. The effectiveness of immunity transference decrease the antibiotic uses and it was observed that colostrum and immunity play a role in restoring the animals' microbiota and need further studies.

Prepartum and postpartum nutritional management to optimize fertility in beef cattle

Background: The cow-calf sector of the beef industry has a constant challenge to provide cattle with the proper nutritional profile to optimize reproductive performance. Reproduction and nutrition are the two most important factorswhen considering profitability in this sector of cattle production. Feed costs account for 63% of the total annual cowcost, and, thus, it is evident that nutritional management plays a major role in the financial viability of beef enterprises.Female infertility and other reproductive diseases account for an estimated yearly cost between $441 and $502 millionfor beef producers.Review: There is evidence suggesting that prepartum nutrition affects subsequent postpartum reproduction in beef cattle.The energy balance of the cows and energy profile of their diet are crucial to reproductive success. Prepartum nutritionis important in ensuring cows remain in a positive energy balance and return to estrus efficiently. Cows grazing nativerange grass pastures and supplemented (0.3 kg of 41% Crude Protein cottonseed meal) to lose body weight (BW) for5 months during gestation, had reduced pregnancy rates (29.5% lower) when compared with cows that were fed (1.4kg of 41% Crude Protein cottonseed meal) to maintain BW. This result suggests that cows that lose weight and energyreserves during gestation may suffer from reduced reproductive performance and pregnancy rates when compared withcows that maintain BW and body condition score (BCS). Postpartum nutrition is an important factor in reducing thepostpartum interval to pregnancy and increasing reproductive efficiency in beef cows. When cattle enter a negativeenergy balance during gestation, they tend to mobilize energy reserves and consequently suffer a reduction in BCS. Ithas been shown that when cows calve at a poor BCS (4 or less on a 9 point scale), increasing postpartum dietary energycan decrease the interval from calving to pregnancy and increase conception rates...(AU)

Prepartum and postpartum nutritional management to optimize fertility in beef cattle

Background: The cow-calf sector of the beef industry has a constant challenge to provide cattle with the proper nutritional profile to optimize reproductive performance. Reproduction and nutrition are the two most important factorswhen considering profitability in this sector of cattle production. Feed costs account for 63% of the total annual cowcost, and, thus, it is evident that nutritional management plays a major role in the financial viability of beef enterprises.Female infertility and other reproductive diseases account for an estimated yearly cost between $441 and $502 millionfor beef producers.Review: There is evidence suggesting that prepartum nutrition affects subsequent postpartum reproduction in beef cattle.The energy balance of the cows and energy profile of their diet are crucial to reproductive success. Prepartum nutritionis important in ensuring cows remain in a positive energy balance and return to estrus efficiently. Cows grazing nativerange grass pastures and supplemented (0.3 kg of 41% Crude Protein cottonseed meal) to lose body weight (BW) for5 months during gestation, had reduced pregnancy rates (29.5% lower) when compared with cows that were fed (1.4kg of 41% Crude Protein cottonseed meal) to maintain BW. This result suggests that cows that lose weight and energyreserves during gestation may suffer from reduced reproductive performance and pregnancy rates when compared withcows that maintain BW and body condition score (BCS). Postpartum nutrition is an important factor in reducing thepostpartum interval to pregnancy and increasing reproductive efficiency in beef cows. When cattle enter a negativeenergy balance during gestation, they tend to mobilize energy reserves and consequently suffer a reduction in BCS. Ithas been shown that when cows calve at a poor BCS (4 or less on a 9 point scale), increasing postpartum dietary energycan decrease the interval from calving to pregnancy and increase conception rates...

RELAÇÕES ENTRE PESO DO BEZERRO À DESMAMA E PESO METABÓLICO DA VACA EM REBANHOS DA RAÇA NELORE

RESUMO WINKLER, Roberto, M.Sc., Universidade Federal de Viçosa, fevereiro de 2019. Relações entre peso do bezerro à desmama e peso metabólico da vaca em rebanhos da raça Nelore. Orientador: Henrique Torres Ventura. Coorientador: Fabyano Fonseca e Silva. Estudos sobre tamanho de bovinos e sua relação com eficiência são desenvolvidos há mais de 200 anos e os resultados indicam que o sistema de produção está intimamente ligado ao tamanho ideal. O presente estudo foi desenvolvido com dados de rebanhos da raça Nelore, de diversas regiões do Brasil, criados à pasto, com objetivo de estudar a produtividade das vacas, através da relação peso à desmama do bezerro/peso da vaca à desmama (RPD). O estudo foi realizado com 4.242 pares de informações de peso à desmama do bezerro e peso da vaca à desmama. O peso da vaca foi transformado em peso metabólico (peso metabólico = peso0,75), devido a maior associação do peso metabólico com eficiência que o peso vivo. Foi realizada análise de resíduos para identificar e remover outliers, sendo utilizado o método delta para determinar o intervalo de confiança para o cálculo do erro padrão da herdabilidade. A estimativa de herdabilidade de RPD foi de 0,31 (0,03), permitindo concluir que a utilização da característica como critério de seleção deverá promover ganhos na eficiência produtiva de vacas Nelore. A utilização de RPD como critério fenotípico de seleção tem mostrado problemas em alguns estudos, mas sua inclusão em índices de seleção, com ponderadores econômicos, parece viável.

WINKLER, Roberto, M.Sc., Universidade Federal de Viçosa, February, 2019. Relationships between calve weaning weight and cow metabolic weight in Nellore herds. Adviser: Henrique Torres Ventura. Co-adviser: Fabyano Fonseca e Silva. Over 200 years studies about cattle size are being accomplished and results show that the production system is deeply connected with ideal size. This study was developed with data of Nellore cattle herds, from different regions of Brazil, raised on pasture, with the goal to study cow productivity, through the ratio weaning weight of the calf/weight of the cow at weaning (RPD). The study was realized with 4.242 information pairs of weaning weight of the calf and cow weight at weaning. Cow weight was converted in metabolic weight (metabolic weight = weight0,75), because metabolic weight is more associated with efficiency as live weight. Analysis of residuals was used to identify and remove outliers and, the delta method for obtaining the confidence interval to calculate the standard error of the estimate of heritability. The heritability estimate for RPD was 0,31(0,03), allowing the conclusion that using RPD as selection criteria should promote gains in cow efficiency of Nellore cattle. The use of RPD as phenotypic selection criteria has showed problems in some studies, but its inclusion in selection indexes, with economic weights, seems to be viable.

AVALIAÇÃO CLÍNICA BUCAL DE BEZERROS COM DOENÇA PERIODONTAL E SUAS CORRELAÇÕES BIOQUÍMICAS SÉRICAS E SALIVARES

As doenças periodontais são associadas ao manejo do solo e à dieta e provocam danos à saúde e ao bem-estar dos bovinos. Da mesma forma afeta o desempenho e a eficiência alimentar em decorrência das dificuldades na mastigação e ruminação. Considerada uma enfermidade multifatorial, na qual as bactérias são necessárias para que ocorra o processo infeccioso, mas não suficientes, elas têm características clínico-patológicas e epidemiológicas particulares. Inicialmente associada à formação de pastagem em extensas áreas das regiões Sudeste, Centro-Oeste e Norte do país, a periodontite pode reincidir após a reforma dos pastos ou alimentação dos animais com forragens recém-cultivadas. Na pecuária extensiva, a doença tende à redução espontânea e gradativa nos sistemas de produção com o decorrer dos anos e na dependência do tipo de solo. Ocorrendo em episódios, ela tem característica sazonal e permanece sob a forma crônica em animais adultos; provocam inflamações dos tecidos de proteção e sustentação dos dentes. Na gengivite e gengivite necrosante, que são percursoras da periodontite, a inflamação está associada à formação do biofilme bacteriano e à resposta imune do hospedeiro. O objetivo geral do presente trabalho foi avaliar clinicamente bezerros com doença periodontal e verificar as correlações bioquímicas séricas e salivares. Dez bezerros desmamados, com idade entre 4 e 6 meses, mantidos em pastejo rotacionado em área reformada foram divididos aleatoriamente em dois grupos (n=5 cada grupo): controle e tratamento. Os animais do grupo tratamento receberam via oral pour-dressing 340 mg de virginiamicina diariamente, por um período de cinco meses, num total de período experimental de seis meses. O exame clínico periodontal foi realizado semanalmente, enquanto as análises bioquímicas séricas e salivares, além das análises hematológicas, mensalmente. Os parâmetros bioquímicos analisados foram proteína total, albumina, ureia, aspartato amino transferase (AST), fosfatase alcalina (FA), gama glutamil transferase (GGT), cálcio, fósforo e magnésio. No exame clínico houve maior prevalência de gengivite e gengivite necrosante no grupo controle. Os animais do grupo tratamento tiveram aumento do ganho de peso e condição corporal. Ao longo do período experimental os animais do grupo controle apresentaram redução significativa das concentrações séricas de albumina, magnésio e uréia, enquanto oscilações significantes na albumina, AST, FA, GGT, ureia e fósforo foram encontrados também no grupo controle, porém para os parâmetros salivares. Os animais do grupo contole apresentaram linfocitose e leucocitose e o grupo tratamento apresentou monocitose. A prevalência de gengivite no rebanho demonstrou uma correlação negativa com a concentração de magnésio sérico, e uma correlação positiva com atividade da FA salivar. Não houve correlação significante entre os parâmetros bioquímicos séricos e salivares entre si. Os resultados evidenciaram que as correlações negativas do parâmetro sérico magnésio com os achados clínicos podem sugerir que este parâmetro pode ser utilizado como um marcador para a gengivite nos bovinos.

Periodontal diseases are associated with soil management and diet and cause damage to the health and well-being of cattle. It also affects performance and food efficiency as a result of difficulties in chewing and rumination. Considered as a multifactorial disease, in which bacteria are necessary for the infectious process to occur, but not enough, they have particular clinical and pathological and epidemiological characteristics. Initially associated with pasture formation in extensive areas of the Southeast, Midwest and Northern regions of the country, periodontitis may recur after pasture reform or feed the animals with freshly grown fodder. In extensive livestock, the disease tends to spontaneous and gradual reduction in production systems over the years and depending on the type of soil. Occurring in episodes, it has a seasonal characteristic and remains chronic in adult animals; inflammation of the protective tissues and support of the teeth. In gingivitis and necrotizing gingivitis, which are precursors of periodontitis, inflammation is associated with the formation of the bacterial biofilm and the immune response of the host. The general objective of the present study was to evaluate clinically calves with periodontal disease and to verify the biochemical correlations between serum and salivary. Ten weaned calves, aged 4 to 6 months, maintained on rotational grazing in a reformed area were randomly divided into two groups (n = 5 each group): control and treatment. The animals in the treatment group were given orally pour-dressing 340 mg of virginiamycin daily for a period of five months for a total of six months experimental period. The periodontal clinical examination was performed weekly, while the serum and salivary biochemical analyzes, in addition to the hematological analyzes, monthly. The biochemical parameters analyzed were total protein, albumin, urea, aspartate amino transferase (AST), alkaline phosphatase (FA), gamma glutamyl transferase (GGT), calcium, phosphorus and magnesium. In the clinical examination there was a higher prevalence of gingivitis and necrotizing gingivitis in the control group. The animals in the treatment group had increased weight gain and body condition. During the experimental period, the animals in the control group showed a significant reduction in the serum concentrations of albumin, magnesium and urea, while significant oscillations in albumin, AST, FA, GGT, urea and phosphorus were also found in the control group, but for salivary parameters . The animals in the contole group had lymphocytosis and leukocytosis and the treatment group showed monocytosis. The prevalence of gingivitis in the herd showed a negative correlation with serum magnesium concentration, and a positive correlation with salivary AF activity. There was no significant correlation between serum and salivary biochemical parameters. The results showed that the negative correlations of the serum magnesium parameter with the clinical findings may suggest that this parameter can be used as a marker for gingivitis in cattle.