Thermoregulatory response of black or red lactating Holstein cows in the hot and cold season in southern Brazil.

Dairy cows in pasture-based systems are more susceptible to heat stress. Holstein cows have the black or red phenotypes, the latter having lower absorbance of solar radiation. Therefore, the study's objective was to evaluate whether cows with red (R) coats are more resistant than black (B) cows to hot weather in a subtropical climate. R and B lactating Holstein cows were evaluated during the cold and hot seasons for internal and surface temperature and sweating rate. In the cold season, body temperature (n = 9/group) did not differ between groups, but the average superficial temperature (n = 13/group) was lower in R cows (B: 30.9 ± 0.3 °C; RW: 29.6 ± 0.3 °C; p = 0.02). In the hot season, under mild to moderate heat stress, mean body temperature (n = 9/group) of R cows was lower (B: 38.75 ± 0.01 °C; R: 38.62 ± 0.1 °C; p=<0.0001), whereas no difference was observed in superficial temperature (n = 17/group). The maximum internal temperature and sweating rate (n = 11/group), measured in the hot season, and the number of evaluations in hyperthermia in both seasons did not differ. Therefore, there were differences in thermoregulation between phenotypes under mild to moderate heat stress conditions. However, considering that only discrete differences were observed, the red and white coat is unlikely to benefit the Holstein cow's welfare under mild to moderate thermal stress.

Induced endometrial inflammation compromises conceptus development in dairy cattle†.

Endometrial inflammation is associated with reduced pregnancy per artificial insemination (AI) and increased pregnancy loss in cows. It was hypothesized that induced endometritis alters histotroph composition and induces inflammatory signatures on conceptus that compromise development. In Experiment 1, lactating cows were assigned to control (CON; n = 23) or to an intrauterine infusion of Escherichia coli and Trueperella pyogenes (ENDO; n = 34) to induce endometritis. Cows received AI 26 days after treatment, and the uterine fluid and conceptuses were collected on day 16 after AI. In Experiment 2, Holstein heifers were assigned to CON (n = 14) or ENDO (n = 14). An embryo was transferred on day 7 of the estrous cycle, and uterine fluid and conceptuses were recovered on day 16. Composition of histotroph and trophoblast and embryonic disc gene expression were assessed. Bacterial-induced endometritis in lactating cows altered histotroph composition and pathways linked to phospholipid synthesis, cellular energy production, and the Warburg effect. Also, ENDO reduced conceptus length in cows and altered expression of genes involved in pathogen recognition, nutrient uptake, cell growth, choline metabolism, and conceptus signaling needed for maternal recognition of pregnancy. The impact of ENDO was lesser on conceptuses from heifers receiving embryo transfer; however, the affected genes and associated pathways involved restricted growth and increased immune response similar to the observed responses to ENDO in conceptuses from lactating cows. Bacterial-induced endometrial inflammation altered histotroph composition, reduced conceptus growth, and caused embryonic cells to activate survival rather than anabolic pathways that could compromise development.

Early versus late body condition score loss in dairy cows: Reproductive performance.

This study aimed to compare milk production and reproductive performance in high yield Holstein cows that lose BCS early and late in the postpartum period. Lactating dairy cows (n = 76) were received first timed AI at 60 to 75 DIM using the farm-managed estradiol-progesterone-GnRH-based timed AI protocol. The BCS of all cows was daily evaluated by automated BCS cameras. Aiming to evaluate the effect of the days in milk (DIM) in which a cow reached the nadir BCS on the reproductive parameters, cows were separated into two groups: early BCS loss (n = 42), cows that reached the nadir BCS ≤ 34 DIM, and late BCS loss (n = 34), cows that reached the nadir BCS > 34 DIM. The optimal cut-off point for determining the relationship between days to nadir BCS and pregnancy by 150 DIM (P150) was calculated using the receiver operating characteristic (ROC) curve. From the ROC analysis, the cut-off was 34 DIM (Se, 80.9%; Sp, 66.7%; AUC, 0.74; P < 0.01). No differences (P>0.05) were detected between groups on the BCS and milk production. The average of milk production in both groups was 46.65 ± 6.15 Kg/day. Cows that reached the nadir BCS early postpartum presented lower (P < 0.01) calving interval and greater (P < 0.01) pregnancy at first AI and P150. In summary, cows that lost BCS early had better reproductive performance and had similar milk yield compared with cows that lost BCS late in the postpartum period.

Effects of substituting sweet potato flour for ground corn on performance, feeding behavior, and metabolism of dairy cows.

The objective of this study was to evaluate the effect of substituting sweet potato flour for ground corn in rations fed to lactating dairy on milk yield and composition, blood metabolites, and feeding behavior. Twenty lactating Holstein cows from 30 to 60 days postpartum were randomly assigned to one of two groups (n = 10 each) and used in a cross-over design trial with two treatments: a standard concentrate with ground corn as an energy source or experimental concentrate with sweet potato flour (SPF) replacing all of the ground corn. Each of the 35-day periods consisted of 14 days for adaptation to diet and 21 days for data and sample collection. Milk yield, dry matter intake (DMI), and feeding behavior were evaluated daily throughout the trial. Milk samples were collected weekly and blood samples were collected every 3 days. Milk was analyzed for fat, protein, lactose, and total solid constituents. Blood was analyzed for glucose, non-esterified fatty acid (NEFA), gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST), total protein (TP), albumin, and urea concentrations. Milk yield (P = 0.62) and composition (fat: P = 0.71; protein: P = 0.12; lactose: P = 0.82; total solids: P = 0.56) were not affected by dietary treatments. There were no differences between treatments in DMI or meal frequency, but total eating time (P = 0.001), feeding time (P = 0.001), and meal duration (P = 0.001) was higher for control compared with SPF. However, feeding rate (P = 0.001) and serum urea concentration (P = 0.001) were higher for SPF compared with control. No differences were observed in serum metabolites and enzymes measured among treatments. The results of this trial indicate that SPF can be substituted for ground corn without impairing the performance, feeding behavior, and metabolism in dairy cows.

Zootechnical and health performance of Holstein x Gir crossbred calves.

Crossbreeding is used to increase production and disease resistance in adult animals, and there is no research to assess the performance of animals in the early stages. The aim of this study was to evaluate the zootechnical and health performance of Holstein x Gir calves (½ HG: ½ Dutch ½ Gir and ¾ HG: ¾ Dutch » Gir), from birth to 80 days of age, and compare metabolic parameters between groups. In this sense, calves were monitored for zootechnical parameters; epidemiological indexes such as morbidity, mortality, recurrence of diarrhea, pneumonia, and other diseases; as well as serum concentrations of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, total proteins, cholesterol, triglycerides, albumin, urea, and paraoxonase1 (PON1). ¾ HG calves showed higher morbidity for diarrhea and remained with diarrhea for longer compared to ½ HG calves, and this was reflected in the average daily weight gain until the 42nd day, with ½ HG calves performing better. There were no differences regarding passive immune transfer between groups, as well as no differences in morbidity and mortality from pneumonia. Regarding biochemical analyses, a difference was found only in the concentrations of PON1, which were higher in ¾ HG calves. The findings show that blood degree influences the occurrence and duration of diarrhea, negatively impacting the zootechnical performance of the animals. Crossbreeding bulls with zebu cattle can be an alternative to increase calf resistance and reduce diarrhea, thus lowering economic losses and improving animal performance.

Sweet Potato Flour as a Replacement for Ground Corn as an Energetic Concentrate / Utilização de farinha de batata-doce como substituto ao milho moído como concentrado energético

ABSTRACT: This study evaluated the effects of different levels of substitution of ground corn by sweet potato flour on intake, digestibility, microbial protein synthesis and total Nitrogen (N) retention in sheep fed mixed diets based on corn silage. Eight castrated male sheep were used, kept in metabolic cages. The animals received fixed proportions of oat hay, corn silage and soybean meal. The control group (0%) received only ground corn, while the other groups received different levels of inclusion of sweet potato flour (SPF) to replace ground corn, in the proportions of 33%, 66%, and 100%. The 0% and 33% groups had lower neutral detergent fiber (NDF) intake than the 66% and 100% groups. There was a trend (P = 0.07) of effect of treatments on crude protein (CP) intake with a significant positive linear effect (P = 0.03). There was a trend (P = 0.07) for treatment effects in N intake with a significant positive linear effect (P = 0.03). The other parameters as urine N excretion (P = 0.91) and feces N excretion (P = 0.16) were not affected by the replacement of ground corn by SPF. Moreover, there was no effect on N retention (P = 0.43) and on efficiency of N use (P = 0.69). Adding SPF to a diet instead of corn did not alter the microbial protein parameters. The inclusion of sweet potato flour did not cause changes in the protein metabolism of animals, suggesting it can be used instead of corn.

RESUMO: O objetivo desse estudo foi avaliar os efeitos dos diferentes níveis de substituição de milho moído por farinha de batata-doce na ingestão, digestibilidade, síntese de proteína microbiana e a retenção de Nitrogênio (N) em ovinos alimentados por dietas com base em silagem de milho. Foram utilizados oito ovinos machos castrados, mantidos em gaiolas metabólicas, divididos em quatro grupos no quadrado latino 4 x 4, totalizando quatro períodos de 15 dias cada. Os animais receberam proporções fixas de feno de aveia, silagem de milho e farelo de soja. O grupo controle (0%) recebeu apenas milho moído, enquanto os outros grupos receberam diferentes níveis de inclusão de farinha de batata doce (FBD) em substituição ao milho moído, nas proporções de 33%, 66% e 100%. Amostras de alimentos e sobras foram coletadas para avaliação do consumo e análise bromatológica. A urina foi coletada para avaliação da síntese proteica microbiana através dos derivados da purina (DP). As fezes foram coletadas para análise e estimativa da digestibilidade. Os grupos de 0% e 33% apresentaram menor consumo de fibra em detergente neutro (FDN) do que os grupos de 66% e 100%. Houve uma tendência (P = 0,07) de efeito dos tratamentos na ingestão de proteína bruta (PB) com efeito linear positivo significativo (P = 0,03). Houve uma tendência (P = 0,07) para os efeitos do tratamento na ingestão de N com um efeito linear positivo significativo (P = 0,03). Os demais parâmetros como excreção de N na urina (P = 0,91) e excreção de N nas fezes (P = 0,16) não foram afetados pela substituição do milho moído pela FBD. Além disso, não houve efeito na retenção de N (P = 0,43) e na eficiência do uso de N (P = 0,69). A adição de FBD a uma dieta em vez de milho não alterou os parâmetros das proteínas microbianas. A inclusão de farinha de batata-doce não causou alterações no metabolismo proteico dos animais, sugerindo que pode ser utilizada no lugar do milho.

Use of Saccharomyces cerevisiae-based products and effects on rumen environment and performance of sheep subjected to dietary changes / Utilização de produtos à base de Saccharomyces cerevisiae e seus efeitos sobre o ambiente ruminal e desempenho de ovinos submetidos a mudanças de dieta

ABSTRACT: Natural additives in ruminant diet optimizes animal performance by controlling or modifying the rumen fermentation pattern. The aim of this study was to evaluate the effects of using Saccharomyces cerevisiae products during abrupt changes in dietary starch concentration on ruminal pH maintenance, performance and metabolism of confined sheep. Twenty adult ewes, crossbred Texel x Corriedale(44.7±6.97 Kg BW) were divided into three groups: Control (n=6), Cultron X (yeast culture; n=7) and Cultron Pro (hydrolyzed yeast; n=7), administered at a dose of 5 g/sheep/day (10x1010CFU/g DM). The experiment lasted 20 days divided into four periods, alternating between 40 and 60% concentrate. Blood and ruminal fluid were collected at the end of each period, and daily dry matter intake was measured to determine the average daily gain (ADG). Blood tests included blood count and biochemical parameters such as glucose, urea, total plasma proteins (TPP), liver enzymes, acute phase proteins and minerals. There was an upward trend in ADG in group Cultron X compared to control in period 3. Although, ruminal pH did not differ between groups, protozoan motility was higher in animals supplemented with hydrolyzed yeast. The Cultron Pro group showed an increase in TPP in periods 3 and 4, and AST in periods 2 and 3 compared to the control group. There was no difference in other metabolites. Yeast supplementation is a potential tool in times of feeding challenge, in which yeast culture is the most effective for improving performance of confined sheep being in improving performance of confined sheep.

RESUMO: A utilização de aditivos naturais na dieta de ruminantes é uma prática que otimiza o desempenho, controlando ou modificando o padrão de fermentação ruminal. O objetivo do estudo buscou avaliar os efeitos da utilização de produtos à base de Saccharomyces cerevisiae durante mudanças na concentração de amido da dieta sobre a manutenção do pH ruminal, desempenho e metabolismo de ovinos confinados. Dessa forma, 20 fêmeas ovinas adultas mestiças das raças Texel e Corriedale (44,7±6,97 PV) foram divididas em três grupos: Controle (n=6), Cultron X (cultura de levedura; n=7) e Cultron Pro (levedura hidrolisada; n=7), administrados na dose de 5 g/ovelha/dia (10x1010ufc/g de MS). O experimento teve duração de 20 dias divididos em quatro períodos, alternando entre 40 e 60% de concentrado. Foram realizadas coletas de sangue e líquido ruminal ao final de cada período e mensuração da ingestão de matéria seca diariamente, a fim de determinar o ganho médio diário (GMD). As análises sanguíneas incluíram hemograma e parâmetros bioquímicos como glicose, ureia, proteínas plasmáticas totais (PPT), enzimas hepáticas, proteínas de fase aguda e minerais. Houve tendência de aumento no GMD no grupo Cultron X em relação ao controle no período 3. Apesar do pH ruminal não diferir entre grupos, a motilidade de protozoários foi melhor nos animais suplementados com levedura hidrolisada. O grupo Cultron Pro apresentou aumento de PPT nos períodos 3 e 4 e aumento nos níveis da enzima hepática AST nos períodos 2 e 3 em comparação ao grupo controle. Não houve diferença nos demais metabólitos. A suplementação com levedura apresentou-se como potencial ferramenta em momentos de desafio alimentar, sendo a cultura de levedura mais eficaz na melhora da performance de ovinos confinados.

Utilização de taninos como aditivo nutricional na dieta de ruminantes / Use of tannins as a nutritional additive for ruminants / Uso de taninos como aditivo nutricional en dieta de rumiantes

Os taninos são compostos fenólicos presentes em plantas, classificados quanto à estrutura química em compostos hidrolisáveis e condensados. Os condensados são adicionados à dieta de ruminantes devido a sua capacidade de formar complexos com proteínas tornando-as não degradáveis no ambiente ruminal. Dessa forma, aumenta o aporte proteico no intestino delgado onde ocorrerá a maior absorção na porção cranial do órgão, o duodeno. A vantagem desse mecanismo é aumentar o aproveitamento da proteína da dieta pelos animais o que influenciará na produtividade e sistema imunológico, entre outros. Os efeitos positivos com a utilização desse composto como aditivo nutricional ainda precisam ser estudados, portanto, o objetivo dessa revisão consiste em demonstrar os resultados, até então conhecidos, da utilização de taninos condensados na dieta de ruminantes.(AU)

Tannins are phenolic compounds present in plants. According to their chemical structure, they can be classified into hydrolysable and condensed compounds. Condensed compounds are added to the ruminant nutrition due to their ability to form complexes with proteins, rendering them as non-degradable in the rumen environment. Thus, it increases the protein supply in the small intestine, where the highest absorption will occur in the duodenum, the cranial portion of the organ. The advantage of this mechanism is the increase of the use of dietary protein by the animals, which will thus influence productivity and the immune system, among others. The positive effects of the use of this compound as a nutritional additive still need to be further investigated, therefore, the purpose of this review is to demonstrate the known results of the use of condensed tannins in the diet of ruminants.(AU)

Los taninos son compuestos fenólicos presentes en plantas, clasificados según la estructura química en compuestos hidrolizables y condensados. Los condensados se agregan a la dieta de rumiantes debido a su capacidad de formar complejos con proteínas, haciéndolas no degradables en el entorno del rumen. Así, aumenta el aporte proteico en el intestino delgado donde habrá mayor absorción en la porción craneal del órgano, el duodeno. La ventaja de ese mecanismo es aumentar el aprovechamiento de la proteína de la dieta por los animales, lo que influirá en la productividad y sistema inmunológico, entre otros. Los efectos positivos con la utilización de ese compuesto, como aditivo nutricional, todavía necesita ser estudiado, el objetivo de esa revisión consiste en demostrar los resultados, hasta ahora conocidos, del uso de taninos condensados en la dieta de rumiantes.(AU)

Atypical evolution after dengue: extradural hematoma of vertebral canal level l4-l5 / Evolução atípica após dengue: formação de hematoma extradural do canal vertebral nível l4-l5 / Evolución atípica después del dengue: formación de hematoma extradural del canal vertebral nivel l4-l5

ABSTRACT The objective of this paper is to report a case of atypical evolution after a classic case of dengue confirmed by serology, in which the formation of an epidural hematoma with low back pain and radiculopathy was observed. The article is a qualitative and descriptive case report. Data were collected from the medical records of the hospital where the patient was treated. In conclusion, the diagnostic correlation of dengue with this rare condition was possible due to radiological comparisons before and after the formation of the extradural hematoma. Level of evidence V; Expert Opinion.

RESUMO O presente trabalho tem como objetivo relatar um caso de evolução atípica após quadro clássico de dengue, confirmada por sorologia, em que foi observada a formação de um hematoma extradural, com dor lombar baixa e radiculopatia. O artigo é tipo relato de caso, qualitativo e descritivo. Os dados foram coletados no prontuário do hospital onde o doente foi atendido. Como conclusão, a correlação diagnóstica da dengue com essa afecção rara foi possível devido a comparações radiológicas pré- e pós-formação do hematoma extradural. Nível de evidência V; Opinião de Especialista.

RESUMEN El presente trabajo tiene como objetivo relatar un caso de evolución atípica después de un cuadro clásico de dengue, confirmado por serología, en el que se observó la formación de un hematoma extradural, con dolor lumbar bajo y radiculopatía. El artículo es tipo relato de caso, cualitativo y descriptivo. Los datos fueron recolectados en el prontuario del hospital en donde el enfermo fue atendido. Como conclusión, la correlación diagnóstica del dengue con esta afección fue posible debido a las comparaciones radiológicas pre y post formación del hematoma extradural. Nivel de evidencia V; Opinión de Especialista.

Prepartum lameness on subsequent lactation in Holstein dairy cows / Impactos da claudicação pré-parto na lactação subsequente de vacas leiteiras da raça Holandês

ABSTRACT: The aim of this study was to confirm the possible consequences of prepartum lameness on subsequent lactation among Holstein cows. In this research, 27 multiparous cows, were monitored from the 30th to 63rd day, relative to calving. Thirty days prior to parturition, the animals were segregated into two groups based on the locomotion score (LS), where LS 1 is attributed to animals without claudication, LS 2 to those with suspected lameness and LS 3, 4 and 5 to those with mild, moderate and severe lameness, respectively; in the lame cows group (LC) (n=15), the animals displayed LS ≥ 3, whereas in the non-lame cows group (NLC) (n=12) they showed LS 1. Milk production, body condition score (BCS) and blood concentration levels of β-hydroxybutyrate (BHB), urea, phosphorus, calcium aspartate aminotransferase (AST), gamma glutamyl transferase (GGT) and total plasma proteins (PPT) were evaluated. Milk production (17.675 ± 0.31 L of milk/day) and blood calcium concentration (7.42 ± 0.12 mg/dL) were lower in the lame cows in comparison to those without lameness (22.27 ± 0.42 L of milk/day and 9.63 ± 0.13 mg/dL). Besides, the lame cows showed higher BCS loss during the early postpartum period. The metabolites AST, GGT, PPT, urea, BHB and phosphorus revealed no difference between the groups during the period evaluated. The lameness evident in cows during prepartum exerted major negative effects on the milk production and calcemia, making the LS evaluation during these period an important tool in the early diagnosis of losses for future lactation.

RESUMO: O objetivo deste estudo foi verificar as consequências da claudicação no período pré-parto no início da lactação subsequente de vacas da raça Holandês. Vinte e sete vacas multíparas foram monitoradas do dia -30 até o dia 63 em relação ao parto. Trinta dias antes do parto os animais foram divididos em dois grupos de acordo com classificação de escore de locomoção (EL) em que EL é atribuído ao animal sem claudicação, EL 2 suspeito de claudicar e EL 3, 4 e 5 representam claudicação leve, moderada e severa, respectivamente. No grupo de vacas claudicantes (n=15) os animais apresentavam EL ≥3 e no grupo controle (n=12) apresentavam EL de 1. Foi mensurada a produção de leite, escore de condição corporal (ECC) e as concentrações sanguíneas de β-hidroxibutirato (BHB), ureia, fósforo, cálcio, aspartato aminotransferase (AST), gama glutamil transferase (GGT) e proteínas plastmáticas totais (PPT). A produção média de leite das vacas claudicantes (17,675 ± 0,31 L/dia) e concentração de cálcio sanguíneo (7,42 ± 0,12 mg/dL) foram menores quando comparadas com as não-claudicantes (22,27 ± 0,42 L/dia e 9,63 17,675 ± 0,13 mg/dL). Além disso, vacas claudicantes perderam mais ECC no pós-parto recente. Os metabólitos AST, GGT, PPT, ureia, BHB e fósforo não diferiram entre grupos durante o período avaliado. A claudicação evidente em vacas no pré-parto apresenta grandes reflexos negativos na produção de leite e calcemia desses animais, tornando o EL pré-parto uma ferramenta importante no diagnóstico precoce de prejuízos na futura lactação.

In vitro fermentation of diets containing sweet potato flour as a substitute for corn in diets for ruminants / Fermentação in vitro de dietas contendo farinha de batata-doce como substituto do milho em dietas para ruminantes

ABSTRACT: With the intensification of production systems, dairy cow feeding has undergone changes creating the need to increase substitute feed options, focusing on more efficient, modern, and sustainable alternatives. Few researches were carried out evaluating the inclusion of sweet potato flour as an energy source in substitution of maize for ruminants. The aim of this study was to evaluate the in vitro gas production of ground corn replacement by sweet potato flour at different levels. For in vitro gas production, four treatments were performed, consisting of corn replacement by sweet potato flour at the levels of 0, 33, 66, and 100%, in a diet consisting of corn silage, soybean meal, and ground corn. In vitro incubations were conducted in sealed bottles containing 50 ml of the inoculum prepared using ruminal fluid and 0.5 g of each treatment. Gas production was determined in 96 consecutive hours. The cumulative gas production was greater when the corn was 100% replaced by SPF (224 ± 1.45 and 231.9 ± 1.45 ml/g DMi for 0 and 100% of replacement, P = 0.01). Degradation rates were 7.10, 7.59, 8.08, and 8.59 ± 0.06% per hour for the 0, 33, 66, and 100% replacement rates, respectively (P<0.001). There was also a difference (P = 0.002) in the lag time, in which diets with the highest SPF inclusion had a lower colonization time. In conclusion, sweet potato flour produced more gas and was more rapidly degraded than corn.

RESUMO: Com a intensificação dos sistemas de produção e o aumento das exigências alimentares das vacas leiteiras criou-se a necessidade de diversificação nas opções de alimentos, focando em alternativas mais eficientes, modernas e sustentáveis. Poucas pesquisas foram realizadas avaliando a inclusão da farinha de batata-doce como fonte de energia em substituição ao milho para ruminantes. O objetivo deste trabalho foi avaliar a produção de gás in vitro da farinha de batata-doce (SPF) em substituição ao milho moído em diferentes níveis. Para a produção de gás in vitro, foram realizados quatro tratamentos, com substituição de milho por farinha de batata-doce a 0, 33, 66 e 100%, em uma dieta com silagem de milho, farelo de soja e milho moído. As incubações foram conduzidas em frascos selados contendo 50 ml do inóculo preparado utilizando o fluido ruminal, solução tampão e 0,5 g de cada tratamento. A produção de gás acumulada foi maior na substituição do milho pela SPF em 100% (224 ± 1.45 e 231,9 ± 1.45 ml/g MSi para as substituições 0 e 100%, P = 0,01). A taxa de degradação foi 7,10, 7,59, 8,08 e 8,59 ± 0,06% por hora nas substituições 0, 33, 66 e 100%, respectivamente (P<0,001). Houve também diferença (P = 0,002) no lag time, em que as dietas com maior inclusão de SPF tiveram tempo de colonização bacteriana menor. Em conclusão, a farinha de batata-doce produziu mais gás e foi degradada mais rapidamente que o milho.

Rumen-protected methionine in cattle: influences on reproduction, immune response, and productive performance / Metionina protegida da degradação ruminal em bovinos: influências na reprodução, resposta imune e desempenho produtivo

Nowadays, information and knowledge generated about the main ingredients used in cattle diets have enabled greater assertiveness in their formulation. Among the ingredients, amino acids stand out as a promising tool, capable of reducing total crude protein (CP) levels and adjusting optimal metabolizable protein concentrations in diets. Nutritional programs allow diets due to amino acid requirements, providing the opportunity to increase the efficiency of the use of dietary nitrogen, increasing the scarce protein concentrates, maintaining or even boosting performance. This review aimed to present the influences of methionine, in its formulation protected from ruminal degradation, according to reproductive parameters, immune response, and productive performance in cattle. Reproduction-related benefits are linked to the early days of embryonic implantation in the uterine environment, which initially secretes through the histotroph produced by endometrial glands, the nutrients needed to develop the conceptus until implantation, and vascular communication with the mother. Given the immune response, the main results are related to the benefits of innate immunity, with marked increase in phagocytic capacity of neutrophils and monocytes, as well as an important antioxidant effect mediated by methionine products, such as glutathione. When evaluating the influences on productivity, the most evident correlation is the increase in protein in the milk of cows supplemented with methionine. Over the past decade, studies investigating the potential benefits of this strategic supplementation in beef cattle were intensified, expanding the opportunities for the development of new experimental projects.(AU)

Atualmente, as informações e o conhecimento gerado sobre os principais ingredientes utilizados em dietas para bovinos possibilitaram maior assertividade em suas formulações. Dentre esses ingredientes, os aminoácidos se destacam como uma ferramenta promissora, capaz de levar à redução nos níveis totais de proteína bruta e ajustar as concentrações ideais de proteína metabolizável nas dietas. Programas nutricionais permitem formular dietas por exigências de aminoácidos, oportunizando o aumento na eficiência de utilização do nitrogênio dietético, reduzindo dispêndios com concentrados ricos em proteína, com a manutenção, ou ainda, incremento de desempenho. Esta revisão buscou apresentar as influências da metionina, em sua formulação protegida da degradação ruminal, frente a parâmetros reprodutivos, resposta imune e desempenho produtivo em bovinos. Os benefícios relacionados à reprodução se mostram ligados aos primeiros dias de implantação embrionária no ambiente uterino, que inicialmente secreta, através do histotrofo produzido por glândulas endometriais, os nutrientes necessários para o desenvolvimento do concepto até a implantação e comunicação vascular com a mãe. Dada a resposta imune, os principais resultados estão relacionados aos benefícios da imunidade inata, com aumento acentuado da capacidade fagocitária de neutrófilos e monócitos, assim como um importante efeito antioxidante mediado por produtos originários da metionina, como a glutationa. Por fim, quando avaliadas as influências em produtividade, a correlação mais evidente é o incremento em proteína no leite de vacas suplementadas com metionina. Na última década, os estudos que investigam os potenciais benefícios dessa suplementação estratégica em bovinos de corte foram intensificados, abrindo um caminho de oportunidades para o desenvolvimento de novos projetos experimentais.(AU)

Relationship between thermal comfort indices and internal temperature of grazing lactating Holstein × Gyr cows in western Amazonia / Relação entre índices de estresse térmico e a temperatura interna de vacas Holandês x Gir lactantes em pastejo na Amazônia Ocidenta

The relationship between the indices of thermal comfort and internal temperature in lactating cows was evaluated inRondônia, western Amazonia in a 2 × 2 crossover trial carried out with eight Girolando cows, ½ Holstein × ½ Gyr (n=4) and Holstein × » Gyr (n=4), grazing palisade grass supplemented with or without soybean oil concentrates. Data logger thermometers adapted to intravaginal devices (hormone free) were used to measure internal temperatures (IT) every 10 min over 48 h. Concomitantly, environmental parameters (air temperature, relative humidity, wind speed, and solar radiation) were collected for the estimation of the temperature-humidity index (THI), equivalent temperature index (ETI), and predicted respiratory rate (PRR). Supplementation with soybean oil did not affect the internal temperature of the cows. IT varied significantly between the genetic groups, with the highest mean observed at night in the Holstein × » Gyr cows, compared with that in the ½ Holstein × ½ Gyr cows (39.54 °C vs 39.06 °C, respectively). THI, ETI, and PRR were significantly and positively correlated with the IT of the Girolando cows; however, the PRR was not found to be adequate in indicating the night-time heat stress in cows.

A relação entre índices de conforto térmico com a temperatura interna de vacas lactantes foi avaliada em Rondônia, na Amazônia Ocidental, em um ensaio crossover 2x2 utilizando oito vacas Girolando, ½ Holandês x ½ Gir (n=4) e Holandês x » Gir (n=4) pastejando capim-marandu suplementadas com concentrados contendo ou não óleo de soja. A temperatura interna (TI) dos animais foi aferida com termômetros eletrônicos adaptados em dispositivos intravaginais (livres de hormônio) a cada 10 minutos durante 48h. Concomitantemente, dados climáticos (temperatura do ar, umidade relativa do ar, velocidade do vento e radiação solar) foram coletados para cálculo dos índices de temperatura e umidade (ITU), índice de temperatura equivalente (ITE) e o índice de frequência respiratória predita (PFR). A suplementação com óleo de soja não afetou a temperatura interna das vacas. A TI variou significativamente entre os grupos genéticos, com a maior média observada à noite nas vacas Holandês × » Gir em relação às ½ Holandês × ½ Gir (39,54 °C vs 39,06 °C, respectivamente). ITU, ITE e PFR tiveram correlação significativa e positiva com a TI de vacas Girolando, mas o PFR não foi adequado para indicar estresse térmico em vacas no período da noite.

Parâmetros bioquímicos clínicos de vacas de alta e média produção de leite, criadas em sistema freestall / Clinical and biochemical parameters of high and medium milk yield cows reared in a freestall system

O objetivo deste trabalho foi avaliar os parâmetros bioquímico-clínicos de vacas primíparas e multíparas de alta e média produção de leite criadas em sistema freestall. Foram utilizadas 174 vacas da raça Holandês, divididas em quatro grupos: primíparas de alta produção (PA, n=37; 42,92±0,78 kg leite/dia); primíparas de média produção (PM, n=50; 26,44±0,91 kg leite/dia); multíparas de alta produção (MA, n=37; 44,28±0,87 kg leite/dia) e multíparas de média produção (MM, n=50; 24,87±0,91 kg leite/dia), com 216±12 dias em lactação. Analisaram-se os seguintes metabólitos: concentrações de: colesterol total, colesterol HDL (HDL), triglicerídeos (TAG), beta-hidroxibutirato (BHB), proteínas totais (PT), albumina, ureia, e a atividade da enzima aspartato aminotransferase (AST). O grupo PM apresentou maiores concentrações de albumina (P = 0,001), colesterol (P = 0,001), HDL (P = 0,002) e TAG (P = 0,010) quando comparado com as do grupo MM. O grupo PA apresentou maiores concentrações de HDL (P = 0,001) quando comparado com a MA. PA apresentou maiores concentrações de HDL (P = 0,023) e AST (P = 0,05) ao se comparar com PM. MA apresentou maiores concentrações de albumina (P = 0,009), colesterol (P = 0,041), HDL (P = 0,053) e TAG (P = 0,052) quando comparado com a MM. As diferenças encontradas nos metabólitos analisados tornam-se importantes no estabelecimento dos valores de referência para uma população regional de categorias semelhantes, além da possibilidade de utilização de parâmetros bioquímico-clínicos na prevenção e monitoramento de transtornos metabólicos.

The aim of this study was to evaluate the clinical and biochemical parameters of primiparous and multiparous cows of high and medium milk yield reared in a freestall system. One hundred seventy-four Holstein cows were used, divided into four groups: high yield primiparous (PA, n = 37; 42.92 ± 0.78 kg milk / day); medium yield primiparous (PM, n = 50; 26.44 ± 0.91 kg milk / day); high yield multiparous (MA, n = 37; 44.28 ± 0.87 kg milk / day) and medium yield multiparous (MM, n = 50; 24.87 ± 0.91 kg milk / day) with 216 ± 12 days in lactation. Blood analysis included: total cholesterol, HDL cholesterol (HDL), triglycerides (TAG), betahydroxybutyrate (BHB), total protein (PT), albumin, urea, and aspartate aminotransferase (AST). The PM group had higher albumin concentrations (P = 0.001), cholesterol (P = 0.001), HDL (P = 0.002) and TAG (P = 0.010) compared to the MM group. PA group had higher HDL concentrations (P = 0.001) than MA. PA had higher HDL (P = 0.023) and AST concentrations (P = 0.05) compared to PM. MA had higher albumin (P = 0.009), cholesterol (P = 0.041), HDL (P = 0.053) and TAG (P = 0.052) concentrations compared to MM. The results found in the analyzed metabolites are important in establishing reference values for a regional population, and also allow the use of these biochemical parameters in the prevention and monitoring of metabolic disorders.

Diets Rich in Polyunsaturated Fatty Acids With Different Omega-6/Omega-3 Ratio Decrease Liver Content of Saturated Fatty Acids Across Generations of Wistar Rats

Our study evaluated how the consumption of diets with low (LOW group - 0.4/1) or high (CON group - 13.6/1) omega-6/omega-3 ratio across generations (F1 and F2) can modulate liver fatty acid (FA) profile and blood biomarkers. Liver content of α-linolenic acid was higher in animals always fed with LOW diet than animals that changed from CON to LOW diet, which by your time was higher than animals always fed with CON diet. Liver saturated FA concentration decreased in both groups from F1 to F2. In conclusion, both diets were efficient in decreasing the saturated FA liver content across generations, the LOW ratio diet was more effective in reducing blood triglycerides and non-esterified fatty acids, and there was a multigenerational effect of the LOW ratio diet, improving the FA profile even when the offspring start receiving the CON diet.

Linoleic and α-linolenic fatty acid consumption over three generations exert cumulative regulation of hepatic expression of genes related to lipid metabolism.

The essential fatty acids, omega-3 and omega-6, consumed during pregnancy can benefit maternal and offspring health. For instance, they could activate a network of genes related to the nuclear receptor peroxisome proliferator-activated receptor α (Ppara) and sterol regulatory element binding transcription factor 1 (Srebf1), which play a role in fatty acid oxidation and lipogenesis. The present study aimed to investigate the effects of diets with different omega-3/omega-6 ratio consumed over three generations on blood biochemical parameters and hepatic expression of Ppara- and Srebf1-related genes. During three consecutive generations adult Wistar rats were evaluated in the postpartum period (21 days after parturition). Regardless of prenatal dietary omega-3/omega-6 ratio, an upregulation in liver tissue was observed for Rxra, Lxra and Srebf1 and a downregulation for Fasn in all the evaluated generations. The diet with higher omega-3/omega-6 ratio decreased triacylglycerol serum levels and resulted in a constant non-esterified fatty acid level. Our results indicated that the PUFAs effect on the modulation of genes related to fatty acid oxidation and lipogenesis is cumulative through generations.

Overfeeding Dairy Cattle During Late-Pregnancy Alters Hepatic PPARα-Regulated Pathways Including Hepatokines: Impact on Metabolism and Peripheral Insulin Sensitivity.

Hepatic metabolic gene networks were studied in dairy cattle fed control (CON, 1.34 Mcal/kg) or higher energy (overfed (OVE), 1.62 Mcal/kg) diets during the last 45 days of pregnancy. A total of 57 target genes encompassing PPARα-targets/co-regulators, hepatokines, growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis, lipogenesis, and lipoprotein metabolism were evaluated on -14, 7, 14, and 30 days around parturition. OVE versus CON cows were in more negative energy balance (NEB) postpartum and had greater serum non-esterified fatty acids (NEFA), ß-hydroxybutyrate (BHBA), and liver triacylglycerol (TAG) concentrations. Milk synthesis rate did not differ. Liver from OVE cows responded to postpartal NEB by up-regulating expression of PPARα-targets in the fatty acid oxidation and ketogenesis pathways, along with gluconeogenic genes. Hepatokines (fibroblast growth factor 21 (FGF21), angiopoietin-like 4 (ANGPTL4)) and apolipoprotein A-V (APOA5) were up-regulated postpartum to a greater extent in OVE than CON. OVE led to greater blood insulin prepartum, lower NEFA:insulin, and greater lipogenic gene expression suggesting insulin sensitivity was not impaired. A lack of change in APOB, MTTP, and PNPLA3 coupled with upregulation of PLIN2 postpartum in cows fed OVE contributed to TAG accumulation. Postpartal responses in NEFA and FGF21 with OVE support a role of this hepatokine in diminishing adipose insulin sensitivity.

Associations between resumption of postpartum ovarian activity, uterine health and concentrations of metabolites and acute phase proteins during the transition period in Holstein cows.

The resumption of ovarian activity, uterine health, severity of the negative energy balance and the synthesis of inflammatory mediators during the transition period in dairy cows are interrelated. Therefore, the aim of this study was to evaluate the association between the resumption of postpartum ovarian activity and the percentage of polymorphonuclear (PMN) cells in endometrial cytology, lipid mobilization and the secretion of acute phase proteins. For this study, 20 multiparous Holstein cows were used. Blood samples that were collected from 21d before calving to 44d in milk (DIM) were analyzed for serum glucose, non-esterified fatty acids (NEFA), insulin, haptoglobin, albumin, paraoxonase and progesterone. Endometrial cytology was performed at 37±2DIM to evaluate the percentage of PMN cells in the uterine flushing. Cows were divided into two groups: (1) ovulatory cows (n=12), which returned to ovarian activity by 44±2DIM; and (2) anovulatory cows (n=8), which did not resume ovarian activity during this period. Ovulatory cows had a lower (P=0.05) percentage of PMN cells in endometrial cytology than anovulatory cows (26.3±8.3% vs. 53.4±16.9%, respectively). Ovulatory cows had higher serum albumin during the pre- (P=0.03) and postpartum periods (P=0.01), and tended to have lower haptoglobin concentrations in the prepartum period (P=0.07) and higher paraoxonase activity in the postpartum period (P=0.09). In conclusion, cows that resumed ovarian activity early in the postpartum period had higher albumin concentrations in the peripartum period, which were associated with a lower percentage of uterine PMN cells.

Effect of porcine somatotropin on metabolism and testicular characteristics of prepubertal pigs / Efeito da somatotrofina suína sobre o metabolismo e características testiculares de suínos pré-púberes

The effect of pST on the testicular characteristics and metabolic parameters of prepubertal pigs was evaluated. Experiment 1 aimed to determine the interval between applications of pST based on the concentrations of circulating IGF-I. Experiment 2 aimed to evaluate the effect of pST on metabolic parameters, testicular characteristics, and expression of GHR, IGF-I and PCNA. In Experiment 1 twelve piglets with 30 days of age were used. The pST Group (n = 6) was submitted to one i.m. injection of pST and the Control Group (n = 6) to one placebo injection. Blood collections were performed until day 7 post pST application to determine IGF-I concentration and metabolic profile. In Experiment 2 twelve piglets with 22 days of age were used. The pST Group was submitted to pST injections every three days, and the Control Group received placebo doses during 30 days. Blood collections were performed every 3 days. Samples of liver and testicular tissue were collected to determine gene expression and testicular characteristics. In Experiment 1 IGF-I concentration was higher for the pST Group (P = 0.02). In Experiment 2 the pST Group had higher body and testicular weight (P=0.06) and increased gene expression of PCNA in testes (P < 0.05). However, a reduction in the number of seminiferous tubules, and Sertoli cells, and in GHR expression (P < 0.05) was observed. Thus, pST administration increased body and testis development in prepubertal pigs, however it reduced the density of seminiferous tubules and Sertoli cells.

Foi investigado o efeito da pST sobre características testiculares e metabolismo de suínos pré-púberes. O Experimento 1 determinou o intervalo entre aplicações de pST, baseado nas concentrações de IGF-I. O Experimento 2 avaliou o efeito da pST sobre o metabolismo, características testiculares e expressão gênica de GHR, IGF-I e PCNA. No Experimento 1, foram usados 12 leitões com 30 dias de idade. O grupo pST (n = 6) foi submetido a uma injeção IM de pST e o grupo Controle (n = 6) a uma injeção de placebo. Coletas de sangue foram realizadas até o dia sete após a aplicação de pST para determinação dos níveis de IGF-I e parâmetros metabólicos. No Experimento 2, foram usados 12 leitões com 22 dias de idade. O grupo pST foi submetido às aplicações de pST a cada 3 dias, e o grupo Controle, às doses de placebo, durante 30 dias. Coletas de sangue foram realizadas a cada três dias. Amostras de fígado e testículo foram coletadas para determinar a expressão gênica e características testiculares. No Experimento 1, a concentração de IGF-I foi maior no grupo pST (P = 0,02). No Experimento 2, o grupo pST teve maior peso corporal e testicular (P = 0,06) e aumento na expressão de PCNA no testículo (P < 0,05). Contudo, foi observada uma redução no número de túbulos seminíferos, células de Sertoli e GHR (P < 0,05). Assim, a administração de pST aumentou o desenvolvimento testicular e corporal de suínos pré-púberes, porém reduziu a densidade de túbulos seminíferos e células de Sertoli.

The use of sodic monensin and probiotics for controlling subacute ruminal acidosis in sheep / O uso de monensina sódica e probióticos para o controle de acidose ruminal subaguda em ovinos

It was to validated a protocol for induction of subacute ruminal acidosis (SARA) (Experiment 1) and test the efficiency of probiotic Saccharomyces cerevisiae or monensin to avoid pH ruminal drops in sheep (Experiment 2). In Experiment 1, six ewes were fasted for two days and then fed most with concentrate during four days. Ewes in this protocol had ruminal fluid pH below 6.0 and kept it for 75 consecutive hours. In Experiment 2, 18 sheep were distributed into three groups: Control (CG, n = 6), monensin (MG, n = 6) and probiotic group (PG, n = 6). SARA was induced according Experiment 1. PG had lower pH (5.7 ± 0.1) than CG (6.0 ± 0.1) (P = 0.05), while MG (5.7 ± 0.1) was similar to both during SARA induction. SARA induction reduced ruminal protozoa population (P < 0.05) and increased chloride concentrations in ruminal fluid (P < 0.01). In serum, SARA increased concentrations of phosphorus (P < 0.01), AST (P < 0.01) and GGT (P < 0.01), but reduced LDH (P < 0.01). In conclusion, the protocol used for SARA induction was able to maintain ruminal pH between 5.5-6.0 for more than 48 hours. However, monensin and probiotics supplementation was not effective in preventing changes in ruminal and serum parameters during SARA.

Foi validado um protocolo para a indução de acidose ruminal subaguda (SARA) (Experimento 1) e testar a eficácia do probiótico Saccharomyces cerevisiae ou monensina na prevenção da queda do pH do fluido ruminal em ovinos (Experimento 2). No Experimento 1, seis ovelhas foram mantidas em jejum por dois dias e, em seguida, alimentadas basicamente com concentrado durante quatro dias. Nesse protocolo as ovelhas mantiveram o pH do fluido ruminal abaixo de 6,0 por 75 horas consecutivas. No Experimento 2, 18 ovelhas foram distribuídas em três grupos: controle (GC, n = 6), monensina (GM, n = 6) e o grupo probiótico (GP, n = 6). A SARA foi induzida de acordo com o Experimento 1. GP apresentaram valores de pH mais baixos (5,7 ± 0,1) do que o GC (6,0 ± 0,1) (P = 0,05), enquanto GM (5,7 ± 0,1) foi semelhante durante a indução de SARA. A indução SARA reduziu a população de protozoários no rúmen (P < 0,05) e aumentou a concentração de cloreto no líquido ruminal (P < 0,01). Durante a SARA observou-se aumento das concentrações séricas de fósforo (P < 0,01), AST (P < 0,01) e GGT (P < 0,01), mas reduziu a de LDH (P < 0,01). Em conclusão, o protocolo utilizado para a indução de SARA foi capaz de manter o pH do rúmen entre 5,5-6,0 por períodos superiores a 48 horas. No entanto, a suplementação com monensina e probióticos não foi eficaz na prevenção das alterações nos parâmetros ruminais e séricos durante SARA.