Influência da restrição alimentar e do estresse térmico sobre parâmetros fisiológicos em ovinos / [Influence of food restriction and heat stress on physiological parameters in sheep]

Objetivou-se avaliar as alterações fisiológicas de ovinos submetidos à restrição alimentar, expostos à radiação solar e à sombra. Dez borregas mestiças foram divididas igualmente em dois grupos: grupo radiação solar - GRS, animais expostos ao sol durante o dia; e grupo sombra - GS, animais alocados dentro de um galpão à sombra. Nos seis dias iniciais de experimento, os animais foram submetidos à restrição alimentar, com acesso apenas à água, já expostos ao sol ou à sombra. Nos seis dias subsequentes, foi ofertada dieta composta por ração e feno de alfafa (3%PV). Os parâmetros avaliados foram frequência respiratória (FR), temperatura retal (TR), ß-hidroxibutirato (BHB), pH urinário, ingestão de matéria seca (IMS) e dados bioclimáticos (temperatura, umidade relativa do ar e índice de temperatura e umidade - ITU). A FR foi o parâmetro em que houve maior diferença significativa entre os grupos (p<0,05). O balanço energético negativo foi constatado em todos os animais (BHB>0,8mmol/L; pH<7,0). Ovelhas que sofrem restrição alimentar durante períodos de alta temperatura e umidade têm menor frequência respiratória e temperatura interna, independentemente de estar na sombra ou pleno sol. Porém, quando normalizado a oferta de alimento as ovelhas em pleno sol têm menor ingestão de matéria seca.(AU)

We aimed to evaluate physiological changes in sheep submitted to food restriction, exposed to the sun or shade. Ten ewe lambs were equally divided into two groups: Sun Radiation Group - GRS, exposed to sun during day hours, and Shade Group - GS, with animals placed inside a barn. In the first six days of experiment, animals were submitted to food restriction, with access to fresh water, already exposed to sun and shade. In the following six days alfalfa hay and concentrate were provided to the animals (3%BW). Parameters assessed were respiratory rate (FR), rectal temperature (TR), ß-hydroxybutyrate, urinary pH, dry matter intake (IMS) and climate data (air temperature, humidity, and temperature-humidity index - ITU). The parameter that most differed between groups was FR. All animals presented negative energy balance (BHB>0.8mmol/L; pH<7,0). Ewe lambs submitted to food restriction during periods of high temperature and humidity have lower respiratory rate and intern temperature, independently of being exposed to sun or shade. However, when food was offered animals exposed to sun had lower dry matter intake.(AU)

The occurrence of diseases and their relationship with passive immune transfer in Holstein dairy calves submitted to individual management in southern Brazil / Ocorrência de doenças e sua relação com a transferência de imunidade passiva em bezerras Holandês criadas em sistema individual no sul do Brasil

Calves are extremely dependent on colostrum intake for the acquisition of passive immunity. This study aimed to determine the occurrence of diarrhea and respiratory diseases and the impact of Failure of Passive Immune Transfer (FPIT) on the health and zootechnical performance of Holstein dairy calves in individual management. This study has been carried out in five commercial farms in Rio Grande do Sul State, Brazil, from March 2017 to January 2018. In this study, 131 calves were followed from birth to 60 days of age. Total Plasmatic Protein (TPP) has been performed to determine passive immune transfer quality in 53 calves (53/131). A daily clinical follow-up has been accomplished aiming at diagnosing diseases and their incidences, and zootechnical measures such as withers height, width of the croup and weight have been evaluated. FPIT rate was 32.07%, diarrhea occurrence and respiratory diseases were 77.9% and 49.6%, respectively. FPIT increased the chances of calves presenting diarrhea and developing respiratory diseases, but no differences on zootechnical performance were found. The frequency of FPIT is still high and is a factor that corroborated the increased risk for diarrhea and respiratory disease but did not influence the performance of calves in the preweaning phase.(AU)

Bezerras são extremamente dependentes da ingestão de colostro para adquirir imunidade passiva. Este estudo teve o objetivo de determinar os índices de ocorrência de diarreia e de doença respiratória, assim como o impacto da falha na transferência de imunidade passiva (FTIP) no desenvolvimento de doenças e no desempenho zootécnico de bezerras Holandês criadas em sistema individual. O estudo foi desenvolvido em cinco propriedades comerciais no Rio Grande do Sul, Brasil, entre março de 2017 e janeiro de 2018. Assim, 131 bezerras foram acompanhadas, do nascimento aos 60 dias de idade. Em 53 animais, foi realizada avaliação de proteínas plasmáticas totais para determinar a qualidade na transferência de imunidade passiva. Acompanhamento clínico diário foi realizado, a fim de diagnosticar doenças e suas incidências, assim como avaliações zootécnicas, como altura de cernelha, largura de garupa, perímetro torácico e peso. O percentual de FTIP foi 32,07%, a ocorrência de diarreias e de doenças respiratórias foi, respectivamente, 77,9% e 49,6%. A FTIP aumentou as chances de as bezerras apresentarem diarreia e doenças respiratórias, mas não alterou o desempenho zootécnico. Conclui-se que a frequência na FTIP ainda é elevada, fator que corroborou o aumento do risco para as diarreias e doença respiratória. Apesar disso, a FTIP não influenciou no desenvolvimento das bezerras na fase de aleitamento.(AU)

Induction of lactation in dairy heifers: milk production, inflammatory and metabolic aspects / Indução de lactação em novilhas leiteiras: produção de leite, aspectos inflamatórios e metabólicos

The aim of this study was to evaluate the metabolic, inflammatory, and hepatic aspects, as well as the milk yield in heifers submitted to protocol for induction of lactation compared to primiparous cows. Sixty Holstein heifers were selected and enrolled into two groups: Control (n= 30), pregnant heifers and Induction heifers (n= 30), non-pregnant femeales, submitted to a lactation induction protocol. Blood samples were collected at: pre-lactation period (weeks -3, -2 and -1) and post-lactation period (weeks 1, 2 and 3), aiming to evaluate glucose, non-esterified fatty acids, paraoxonase-1, albumin, ALT, GGT and cortisol. The protocol efficiently induced lactation in all the heifers, which produced 74.54% of the total production of milk from primiparous cows. In the pre-lactation period, induced animals presented higher concentrations of non-esterified fatty acids than the Control heifers, and the opposite was observed in the post lactation period. In both moments albumin and ALT were lower in the Induction group, and paraoxonase-1 activity and GGT concentrations were higher, compared to the Control. Thus, lactation induction protocol is efficient to initiate milk production in dairy heifers with no considerable changes in energetic, metabolic and hepatic profile when compared to heifers in physiological lactation.(AU)

O objetivo deste estudo foi avaliar os perfis metabólico, inflamatório, hepático e a produção de leite de novilhas induzidas à lactação comparadas a primíparas. Sessenta novilhas da raça Holandês foram selecionadas e alocadas em grupos: controle (n=30), novilhas prenhas, e indução (n=30), novilhas vazias submetidas a um protocolo de indução de lactação. As amostras de sangue foram coletadas nas semanas -3, -2 e -1 (pré-lactação) e nas semanas 1, 2 e 3 (pós-início de lactação) para avaliação de glicose, ácidos graxos não esterificados, paraoxonase-1, albumina, ALT, GGT e cortisol. O protocolo induziu eficientemente a lactação em todas as novilhas, que produziram 74,54% da produção total de leite do controle. No período pré-lactação, o grupo indução apresentou maiores concentrações de ácidos graxos não esterificados que o controle, e o oposto foi observado pós-lactação. Em ambos os momentos, albumina e ALT foram menores no grupo indução, e a atividade da paraoxonase-1 e as concentrações de GGT foram maiores, em comparação ao controle. Assim, o protocolo de indução de lactação foi eficiente para iniciar a produção de leite em novilhas induzidas, além de terem sido observadas alterações nos perfis energético, metabólico e hepático em comparação a novilhas em lactação fisiológica.(AU)

Avaliação metabólica de um dispositivo intravaginal polimérico para a administração de cálcio e magnésio em ruminantes / Metabolic evaluation of a polymer intravaginal device for the administration of calcium and magnesium in ruminants

O objetivo do estudo foi avaliar a disponibilidade de cálcio (Ca2+) a partir de duas formas farmacêuticas (oral e intravaginal) e o seu efeito sobre o metabolismo de ruminantes. O estudo foi realizado na fazenda experimental da Universidade Federal de Pelotas, foram estudadas 24 ovelhas lactantes, divididas de forma randomizada em 4 grupos: dispositivo tratamento (DT); dispositivo controle (DC); oral tratamento (OT); e oral controle (OC). Os animais tratados receberam formiato de cálcio e cloreto de magnésio, as avaliações foram realizadas após a administração dos tratamentos. Foi feita avaliação de cálcio total (CaT), magnésio (Mg), proteínas plasmáticas totais (PPT), aspartato aminotransferase (AST), gama glutamil transpeptidase (GGT), ureia, albumina e pH urinário, e realizado exame clínico em todos os animais. As concentrações séricas de CaT, CaI e Mg diferiram entre os grupos (P≤ 0,05), os animais dos grupos DT e DC, diferiram nas três avaliações, o grupo DT apresentou as maiores médias, sendo significativamente igual ao grupo OT. Não houve diferença nas concentrações séricas de PPT, AST, GGT, Albumina, Ureia e pH urinário. Conclui-se que a disponibilidade sanguínea de CaT, CaI e Mg é igual quando a administração de formiato de cálcio e magnésio é por via intravaginal ou por via oral, sem alterar outros parâmetros metabólicos avaliados.(AU)

The aim of the study was to evaluate the availability of calcium (Ca2+) from two pharmaceutical forms (oral and intravaginal) and its effect on the metabolism of ruminants. The study was carried out at the experimental farm of the Federal University of Pelotas. Twenty-four lactating ewes were randomly divided into 4 groups: treatment device (TD); control device (DC); oral treatment (OT); and oral control (OC). Treated animals received calcium formate and magnesium chloride, evaluations were performed after administration of the treatments. Total calcium (CaT), magnesium (Mg), total plasma proteins (PPT), aspartate aminotransferase (AST), gamma glutamyl transpeptidase (GGT), urea, albumin and urinary pH, and clinical examination were performed on all animals. Serum CaT, CaI and Mg levels differed between the groups (P≤ 0.05), the animals in the DT and DC groups differed in the three evaluations, the DT group had the highest mean values, being significantly equal to the OT group. There was no difference in the serum concentrations of PPT, AST, GGT, Albumin, Urea and urinary pH. In conclusion, the blood availability of CaT, CaI and Mg is the same when administration of calcium and magnesium formate is intravaginal or orally, without altering other metabolic parameters evaluated.(AU)

Limits of grape byproduct inclusion in diets for lambs: Zinc supplementation to prevent copper poisoning.

The aims of the current study were to assess the inclusion levels of grape byproduct replacing jiggs hay in lambs diets and to evaluate signs of copper poisoning. Thirty-four Texel and Corriedale crossbred female lambs were used in a randomized block experimental design. The treatments comprised four levels of grape byproduct (0; 100; 200 and 300 g/kg DM) in replacement of jiggs hay. The diets were adjusted to the same ZnCu ratio (6:1) of the basal diet. Grape byproduct consumption at up to 30%, led to similar weight gain in the different treatments (P = .92), which was suitable for growing lambs. Grape byproduct in the diet had linear effect on GGT (P < .001) and AST (P < .0001) enzymes as well as on total bilirubin (P = .05). In addition, the highest grape byproduct addition showed the highest consumption of hay (P < .01). Hay replacement by grape byproduct at up to 300 g/kg in the DM was satisfactory to weight gain and did not negatively affect feed intake and weight gain of growing lambs. Maintaining zinc:copper ratio in sheep diets is not effective in preventing liver damage caused by increased dietary copper concentrations over a period of 70 days.

Effect of mature size and body condition of Nelore females on the reproductive performance.

The size and body condition of cows can affect their reproductive efficiency. However, few studies reported genetic correlations between these traits in beef cattle. Thus, we estimated the genetic parameters and correlations between weight (MW), height (MH) and body condition score (BCS) of cows and reproductive traits (SC: scrotal circumference, AFC: age at first calving, GL: gestation length, DC: days to calving, and CI: calving interval) in Nelore animals. In addition, it has also obtained direct and correlated responses aiming at determining whether changes in cow size and body condition may affect the herd reproductive performance. A series of two-trait Bayesian analyzes were performed including MW, MH or BCS with each of the reproductive traits. The heritability estimated for MW, MH and BCS were 0.46 ±â€¯0.02, 0.35 ±â€¯0.01 and 0.17 ±â€¯0.02, indicating an involvement of additive gene action mainly in cows' size determination. For the reproductive traits of females, heritability ranged from 0.05 ±â€¯0.00 for CI to 0.18 ±â€¯0.01 for GL, and was 0.37 ±â€¯0.01 for SC. Low repeatability were estimates for GL (0.19 ±â€¯0.00), DC (0.19 ±â€¯0.00) and CI (0.05 ±â€¯0.00). The MW was positive correlated with AFC (0.23 ±â€¯0.08), CI (0.25 ±â€¯0.15) and, with lower magnitude, of GL (0.14 ±â€¯0.03). Null genetic correlations were obtained between MW with SC (0.03 ±â€¯0.03) and DC (-0.01 ±â€¯0.04). The MH showed positive and low genetic association with all female reproductive traits, but negative with SC (-0.08 ±â€¯0.03). Negative and favorable genetic correlations were estimated between BCS and females reproductive traits, but unfavorable with SC (-0.13 ±â€¯0.06). In summary, the negative impact of increase the size of Nelore females on their reproductive performance is expected to be small in tropical regions. The use of sires with high genetic breeding values for SC should result in slight reduction of BCS of cows, but no effective genetic response in female size is expected. Selection based on BCS should promote little improvement in reproductive efficiency of cows.

Genetic analysis of age at first calving, accumulated productivity, stayability and mature weight of Nellore females.

The female reproductive performance, productivity and size are strongly associated with production efficiency of herds raised in a tropical environment. The age at first calving (AFC), accumulated productivity (AP), stayability (STAY) and mature weight (MW) could be used as indicators of these traits. In this study, the genetic parameters and correlations between AFC, AP, STAY and MW measured in Nellore females were estimated, in order to provide support for the beef cattle evaluation programs. In addition, the genetic changes for these traits were obtained. The (co)variance components were estimated by Gibbs sampling by four-trait multivariate analysis, using a threshold animal model for STAY and linear animal model for the other traits (AFC, AP and MW). Heritability of AFC, AP and STAY showed low values, with posterior means of 0.13 ± 0.02, 0.14 ± 0.01 and 0.19 ± 0.03, respectively. On the other hand, for MW were estimated mean heritability of 0.44 ± 0.03 and repeatability of 0.77 ± 0.03, demonstrating the importance of genetic and permanent environmental effects for the expression of beef cows' size. The AFC showed null genetic correlation with AP (-0.06 ± 0.12) and MW (0.01 ± 0.09) and low and negative with STAY (-0.15 ± 0.11). The AP showed high genetic correlation with STAY (0.86 ± 0.03) and weak with MW (0.23 ± 0.09). Positive and moderate genetic association was estimated between STAY and MW (0.66 ± 0.05). Annual direct genetic trends of 0.19 kg, 0.30 units and 0.10 kg were estimated for AP, STAY and MW, respectively, and were significant (P < 0.05) for STAY and MW. For AFC, negative and favorable annual genetic change was estimated (-0.08 months, P < 0.05). In this population, the selection of heifers for an early reproductive age should have little influence, however favorable, in the time that the cows remain in the herd. The use of AP as a selection criterion should result in smaller changes in the females' mature weight when compared to selection based on STAY.

Effect of oestrous synchrony between embryo donors and recipients, embryo quality and state on the pregnancy rate in beef cattle.

This study aimed to evaluate the effect of oestrous synchrony between donors and recipients and the embryo quality on the pregnancy rate in beef cow recipients. The experiment was performed over two years at an embryo transfer (ET) centre in Southern Brazil. Ninety Aberdeen Angus cows were subjected to superovulation (SOV) protocols, resulting in the recovery of 1,048 transferable embryos. Eleven groups were formed with intervals of 6 hr, from -30 to +30 hr, with respect to recipient versus donor oestrous detection. Evaluation of embryo quality was according to the IETS guidelines. The overall pregnancy rate was 52%. Effects related to donor and recipient oestrous synchronization on pregnancy rate were observed (p = .01), ranging from 36% to 50%. The embryo quality rate affected the pregnancy rate, where Grade I resulted in 57% and Grade III in 43% of pregnancy (p < .001). The embryonic state (frozen or fresh) showed no (p > .05) effect on pregnancy rate: 53% for fresh embryos and 44% for frozen embryos. The odds ratio for explanatory variables causing pregnancy indicated that Grade III embryos had 31% less chance of conception compared to Grade I. Thus, oestrous synchrony between donor and recipient, considering ±30 hr apart, can affect the pregnancy rate along with embryo quality.

Parâmetros clínicos, hematológicos e bioquímicos de novilhas com hipocalcemia subclínica pré-parto suplementadas com dieta aniônica / Anionic diet on clinical, haematological and biochemical parameters of heifers with subclinical hypocalcemia prepartum

A hipótese do presente estudo consiste em que uma dieta aniônica prolongada acarretaria uma mobilização mais rápida do cálcio sanguíneo. O objetivo proposto foi avaliar parâmetros clínicos, hematológicos e bioquímicos de novilhas, com hipocalcemia subclínica, submetidas a diferentes períodos de fornecimento de dieta aniônica no pré-parto. Foram utilizadas nove novilhas da raça Holandês induzidas à hipocalcemia subclínica no pré-parto, divididas em três grupos: G0 = sem dieta aniônica antes da indução; G11 = 11 dias de dieta aniônica pré-indução; e G15 = 15 dias de dieta aniônica pré-indução. Foi realizado exame clínico antes e depois da indução, e avaliaram-se cálcio total e ionizado, magnésio e albumina nos dias -2, 0, 1, 2 e 3 (dia 0 = momento da indução) e parâmetros hematológicos nos dias 0, 1, 2 e 3. O G11 apresentou maiores concentrações de cálcio total e ionizado que o G0 e maiores níveis de cálcio total que o G15 (P<0,01). O magnésio teve maiores valores no G15 quando comparado aos outros grupos (P<0,01). O G0 apresentou os maiores valores de monócitos e neutrófilos bastonetes (P<0,01). A dieta aniônica por 11 dias é suficiente para manter a homeostase do cálcio e a resposta leucocitária em novilhas desafiadas a uma diminuição do cálcio sanguíneo.(AU)

This study's hypothesis is that cows receiving anionic diet for a longer period respond more quickly to decreased blood calcium. The aim was to evaluate the heifers' clinical, hematological, and biochemical parameters, with subclinical hypocalcemia, subjected to different periods of anionic diet supply during antepartum. Nine heifers were induced to subclinical hypocalcemia during antepartum, sorted in 3 groups: G0 = no anionic diet before induction; G11= eleven days of anionic diet before induction; and G15 = fifteen days of anionic diet before induction. Examinations were held before and after induction and total and ionized calcium, magnesium and albumin were evaluated from days -2, 0, 1, 2 and 3, day 0 being the moment of induction; hematologic parameters were evaluated at days 0, 1, 2 and 3. G11 presented a higher total and ionized calcium concentration than G0 and higher total calcium concentration than G15 (P < 0.01). Magnesium had its highest values at G15 when compared to the other two groups (P < 0.01). G0 presented its highest values of monocytes and neutrophils rods (P<0.01). The eleven days of anionic diet supply were enough to maintain calcium homeostasis and leukocyte response in heifers challenged to reduction in blood calcium.(AU)

Combinação de butafosfan e cianocobalamina no metabolismo da glicose em vacas leiteiras após o parto / Combined of butaphosphan and cyanocobalamin on the glucose metabolism of dairy cows after calving

A hipótese deste estudo é de que o uso da combinação de butafosfan e cianocobalamina pode melhorar a resistência periférica à insulina, aumentar a quantidade de glicose disponível para a glândula mamária e a produção de leite. Assim, o objetivo foi investigar os efeitos combinados de butafosfan e cianocobalamina sobre o metabolismo da glicose em vacas leiteiras no período pós-parto. Vinte e uma vacas leiteiras foram divididas em dois grupos: grupo controle (CON, n= 11), que recebeu cinco aplicações de solução salina (20mL / animal 0,9% NaCl), e grupo Catosal(r) (ABC, n= 10), que recebeu cinco aplicações de 20mL de uma solução contendo as substâncias butafosfan e cianocobalamina (B12 Catosal(r), 100mg da substância butafosfan e 50µg de cianocobalamina por mL). As aplicações foram realizadas por via intramuscular, nos dias sete, 12, 17, 22 e 27 pós-parto. As amostras de sangue foram coletadas para a avaliação das concentrações plasmáticas de fósforo, glicose, ácidos graxos não esterificados (AGNE), albumina, aspartato aminotransferase (AST) e creatina quinase (CK). Nos dias oito e 28 pós-parto, os animais foram pesados e submetidos aos testes de tolerância à glicose e à insulina. O tratamento promoveu perda de peso (ABC 40,4kg, CON 10,73kg, P<0,05) e aumento da AST (ABC 62,92 ±3,31U/L, CON 53,11±3,49 U / L, P<0,05) e dos níveis de CK (ABC 134,09± 19,08U / L, CON 79,43 ± 18,27U / L). Os grupos não diferiram quanto ao metabolismo (área sob a curva) da glicose nos dias oito e 28, porém os animais tratados tiveram um aumento na glicemia (P<0,05) no dia 28 pós-parto (97,54 ± 8,54mg / dL), após a administração de insulina, em comparação ao dia oito (83,01 ± 8,54mg / dL). Assim, pode-se concluir que a combinação de butafosfan e cianocobalamina melhora a adaptação do metabolismo da glicose em vacas leiteiras no início da lactação.(AU)

The hypothesis of this study is that the combined use of butaphosphan and cyanocobalamin could enhance peripheral insulin resistance, increasing the amount of glucose available for the mammary gland and milk production. Thus, our aim was to investigate the combined effects of butaphosphan and cyanocobalamin on the glucose metabolism in dairy cows during the postpartum period. Twenty one dairy cows were divided into two groups: Control Group (CON, n= 11), that received 5 injections of saline solution (20mL/animal 0.9 % NaCl), and Catosal group (ABC, n= 10) which received 5 injections of 20mL of a Butafosfan and Cyanocobalamin solution (Catosal(r) B12, 100mg of Butafosfan and 50µg Cyanocobalamin for mL). The injections were performed by intramuscular route, on days 7, 12, 17, 22 and 27 postpartum. Blood samples were taken on these days to evaluate plasma concentrations of phosphorus, glucose, non-esterified fatty acids (NEFA), albumin, aspartate aminotransferase (AST) and creatine kinase (CK). On days 8 and 28 postpartum, the animals were weighted and subjected to the glucose tolerance and insulin challenge tests. The treatment promoted weight loss (ABC 40.4kg, CON 10.73kg, P< 0.05) and increased AST (ABC 62.92 ±3.31U/L, CON 53.11 ±3.49U/L, P< 0.05) and CK levels (ABC 134.09 ±19.08U/L, CON 79.43 ±18.27U/L). Glucose metabolism (area under the curve) did not differ (P> 0.05) among groups on days 8 and 28; however, ABC animals showed higher serum glucose levels (P< 0.05) after insulin administration on day 28 postpartum (97.54 ±8.54mg/dL) when compared to day 8 (83.01 ±8.54mg/dL). It could be concluded that the combined use of butaphosphan and cyanocobalamin interferes positively with the adaptation of glucose metabolism in dairy cows in early lactation.(AU)

Different doses of equine chorionic gonadotropin on ovarian follicular growth and pregnancy rate of suckled Bos taurus beef cows subjected to timed artificial insemination protocol.

This study evaluated the effect of different doses of eCG (control, 300 or 400 IU) administered at progesterone (P4) device removal in suckled Bos taurus beef cows undergoing a timed artificial insemination (TAI) protocol. A total of 966 cows received a P4 insert and 2.0 mg intramuscular estradiol benzoate at the onset of the synchronization. After 9 days, P4 insert was removed, and 12.5 mg of dinoprost tromethamine and 1 mg of estradiol cypionate were administered, followed by TAI 48 hours later. Then, the cows received one of three treatments as follows: control (n = 323), 300 (n = 326), or 400 IU of eCG (n = 317). A subset (n = 435) of cows in anestrus had their ovaries evaluated using ultrasound at the time of P4 removal and at TAI. Data were analyzed by orthogonal contrasts (C): C1 (eCG effect) and C2 (eCG dose effect). Estrous occurrence (control = 53.7%, 300 IU = 70.6%, and 400 IU = 77.0%) and pregnancy per artificial insemination (control = 29.7%, 300 IU = 44.8%, and 400 IU = 47.6%) were improved by eCG treatment (C1; P = 0.0004 and P < 0.0001, respectively). Furthermore, the cows receiving eCG presented larger follicles at TAI (control = 13.5 ± 0.3 mm, 300 IU = 14.0 ± 0.2 mm, and 400 IU = 15.1 ± 0.3 mm; P < 0.0001; C1). However, there was no effect of eCG dose on any response variables studied (C2; P > 0.15). In conclusion, the eCG treatment administered at the time of P4 removal increased the occurrence of estrus, the larger follicles at TAI, and pregnancy per artificial insemination of suckled B taurus beef cows. Despite the greater occurrence of estrus in noncyclic cows receiving 400 IU of eCG, both eCG doses (300 and 400 IU) were equally efficient to improve pregnancy to artificial insemination.

Prepartum administration of recombinant bovine somatotropin (rBST) on adaptation to subclinical ketosis of the ewes and performance of the lambs / Administração pré-parto de somatotropina bovina recombinante (rBST) na adaptação da cetose subclínica de ovelhas e no desempenho dos cordeiros

The aim of this study was to determine the effect of prepartum rbST injection on the metabolic profile of pregnant ewes induced to subclinical ketosis, as well as the metabolism until seven days of life and weight gain until seven weeks of life of the lambs. Twenty seven pregnant ewes of the pantaneiro genetic group were used, divided into two groups: rbST group (n = 14) and control group (n = 13). The rbST group received two applications of 1 mg/kg of rbST, at 97 and 111 days gestation, while the control group received placebo injections. There were significant differences between groups in levels of GGT in the ketosis post induction period and BHB concentrations in the postpartum period. Concentrations of glucose, urea, phosphorus, albumin, cholesterol, AST, NEFA and insulin were not different between dams from the two groups in different periods of the study (P>0.05). There was an effect of rbST on body weight observed already at fourteen days of life (P<0.0001), there was an increase in serum phosphorus levels at birth of lambs (P=0.0014), and albumin at seven days of life (P = 0.0014) of the lambs, with no difference between groups for the other metabolites. Therefore, the use of rbST was effective in increasing the weight of the lambs until the seventh week of life. In addition, rbST treatment had positive effects on the dam metabolism with reduction of liver overload, as indicated by decreased GGT after ketosis induction and decreased BHB at the postpartum period.

O objetivo deste estudo foi determinar o efeito da administração pré-parto de rbST sobre o perfil metabólico de ovelhas induzidas à cetose subclínica, assim como sobre o metabolismo até sete dias de vida e ganho de peso até sete semanas de vida dos cordeiros. Vinte e sete ovelhas prenhas do grupo genético pantaneiro foram divididas em dois grupos: grupo rbST (n = 14) e grupo controle (n = 13). O grupo rbST recebeu duas aplicações de 1mg/kg de rbST, aos 97 e 111 dias de gestação, ao passo que o grupo controle recebeu injeções de placebo. Houve diferenças significativas entre os grupos nos níveis de GGT no período de pós-indução de cetose e concentrações de BHB no período pós-parto. As concentrações de glicose, ureia, fósforo, albumina, colesterol, AST, NEFA e insulina não foram diferentes entre os grupos nos diferentes períodos do estudo (P>0,05). Houve um efeito de rbST no peso corporal dos cordeiros já observado nos 14 dias de vida (P<0,0001), verificou-se um aumento dos níveis séricos de fósforo ao nascimento de cordeiros (P=0,0014) e albumina de sete dias de vida (P=0,0014 ), e não houve diferença entre os grupos para os outros metabólitos. Portanto, a utilização de rbST foi eficaz em aumentar o peso dos cordeiros até a sétima semana de vida. Além disso, a aplicação de rbST teve efeitos positivos no metabolismo com a redução da sobrecarga do fígado, como indicado pela diminuição da GGT após a indução da cetose e diminuição de BHB no período pós-parto.