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.

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.

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

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.

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.

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

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.(AU)

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.(AU)

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

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.(AU)

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.(AU)

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.

Evaluation of biochemical profile and rumen fluid parameters of sheep supplemented with Saccharomyces cerevisiae and subjected to an abrupt diet change / Avaliação do perfil bioquímico e parâmetros do líquido ruminal de ovinos suplementados com Saccharomyces cerevisiae submetidos à troca abrupta de dieta

This study examines rumen-fluid parameters and the biochemical profile of feedlot sheep supplemented with a commercial product composed of yeast culture and enzymatically hydrolyzed yeast during an abrupt change of diet. Eight sheep at 30 months of age, with an average weight of 40.2 ± 3.4 kg, were housed in individual stalls where they received the same diet twice daily, which was formulated according to the National Research Council [NRC] (2007). The animals were divided into two groups, namely, supplemented with Saccharomyces cerevisiae (SG, n = 4) and control (CG, n = 4). The experiment consisted of three periods: the first (seven days) consisted of an acclimation to the roughage-only diet; in the second period (five days), the animals of SG started to receive supplementation; lastly, in the third period (five days), all animals underwent a sudden change of diet, which was characterized by an alteration from 100% roughage to a 50:50 ratio (roughage:concentrate) without prior adaptation. Blood samples were collected to evaluate albumin, aspartate amino transferase, calcium, gamma glutamyl transferase, globulins, glucose, magnesium, potassium, sodium, total plasma proteins and urea. Rumen fluid was harvested to evaluate physical aspects. Supplementation increased the protozoa count; the rate of sedimentation and fluctuation remained within the physiological parameters; and total plasma proteins and globulin decreased. Therefore, the yeast appears to be a promising alternative for reducing the deleterious effects of an abrupt change of diet.(AU)

Este estudo avaliou os parâmetros do líquido ruminal e o perfil bioquímico de ovinos confinados suplementados com um produto comercial composto por cultura de levedura e levedura hidrolisada enzimaticamente durante mudança abrupta de dieta. Foram utilizadas oito ovelhas, com 30 meses deidade e peso médio de 40,2±3,4kg, mantidas em baias individuais e receberam a mesma dieta duas vezes ao dia, formulada de acordo com o NRC (2007). Os animais foram distribuídos em dois grupos: suplementado com Saccharomyces cerevisiae (GS, n=4) e controle (GC, n=4). O experimento foi constituído de três períodos, o primeiro (sete dias) destinado a adaptação à dieta a base exclusivamente de volumoso, o segundo período (cinco dias) onde os animais do grupo GS passaram a receber suplementação e um último período (cinco dias) onde todos os animais sofreram mudança brusca de dieta, que foi caracterizada por alteração de 100% do volumoso para uma dieta na relação de 50:50 (volumoso:concentrado), sem adaptação prévia. Foram coletadas amostras de sangue, para avaliação de albumina, AST, cálcio, GGT, globulinas, glicose, magnésio, potássio, sódio, PPT (proteínas plasmáticas totais) e ureia. E líquido ruminal para avaliação de aspectos físicos. A suplementação aumentou a contagem de protozoários, a taxa de sedimentação e flutuação manteve-se dentro do fisiológico e houve redução em PPT e globulina mostrando-se uma alternativa promissora na redução dos efeitos deletérios da troca abrupta de dieta.(AU)

Evaluation of biochemical profile and rumen fluid parameters of sheep supplemented with Saccharomyces cerevisiae and subjected to an abrupt diet change / Avaliação do perfil bioquímico e parâmetros do líquido ruminal de ovinos suplementados com Saccharomyces cerevisiae submetidos à troca abrupta de dieta

This study examines rumen-fluid parameters and the biochemical profile of feedlot sheep supplemented with a commercial product composed of yeast culture and enzymatically hydrolyzed yeast during an abrupt change of diet. Eight sheep at 30 months of age, with an average weight of 40.2 ± 3.4 kg, were housed in individual stalls where they received the same diet twice daily, which was formulated according to the National Research Council [NRC] (2007). The animals were divided into two groups, namely, supplemented with Saccharomyces cerevisiae (SG, n = 4) and control (CG, n = 4). The experiment consisted of three periods: the first (seven days) consisted of an acclimation to the roughage-only diet; in the second period (five days), the animals of SG started to receive supplementation; lastly, in the third period (five days), all animals underwent a sudden change of diet, which was characterized by an alteration from 100% roughage to a 50:50 ratio (roughage:concentrate) without prior adaptation. Blood samples were collected to evaluate albumin, aspartate amino transferase, calcium, gamma glutamyl transferase, globulins, glucose, magnesium, potassium, sodium, total plasma proteins and urea. Rumen fluid was harvested to evaluate physical aspects. Supplementation increased the protozoa count; the rate of sedimentation and fluctuation remained within the physiological parameters; and total plasma proteins and globulin decreased. Therefore, the yeast appears to be a promising alternative for reducing the deleterious effects of an abrupt change of diet.

Este estudo avaliou os parâmetros do líquido ruminal e o perfil bioquímico de ovinos confinados suplementados com um produto comercial composto por cultura de levedura e levedura hidrolisada enzimaticamente durante mudança abrupta de dieta. Foram utilizadas oito ovelhas, com 30 meses deidade e peso médio de 40,2±3,4kg, mantidas em baias individuais e receberam a mesma dieta duas vezes ao dia, formulada de acordo com o NRC (2007). Os animais foram distribuídos em dois grupos: suplementado com Saccharomyces cerevisiae (GS, n=4) e controle (GC, n=4). O experimento foi constituído de três períodos, o primeiro (sete dias) destinado a adaptação à dieta a base exclusivamente de volumoso, o segundo período (cinco dias) onde os animais do grupo GS passaram a receber suplementação e um último período (cinco dias) onde todos os animais sofreram mudança brusca de dieta, que foi caracterizada por alteração de 100% do volumoso para uma dieta na relação de 50:50 (volumoso:concentrado), sem adaptação prévia. Foram coletadas amostras de sangue, para avaliação de albumina, AST, cálcio, GGT, globulinas, glicose, magnésio, potássio, sódio, PPT (proteínas plasmáticas totais) e ureia. E líquido ruminal para avaliação de aspectos físicos. A suplementação aumentou a contagem de protozoários, a taxa de sedimentação e flutuação manteve-se dentro do fisiológico e houve redução em PPT e globulina mostrando-se uma alternativa promissora na redução dos efeitos deletérios da troca abrupta de dieta.

Serum metabolic markers pre and postpartum in holstein cows according to the mastitis occurrence

Background: Bovine mastitis causes major economic losses for milk producers by reducing the quantity and the quality of the milk or even leading to the complete loss of the mammary gland secretory capacity. During the transition period, dairy cows are susceptible to infectious diseases; therefore, markers that allow early identification of cows in higher risk of developing diseases are especially useful at this time. Therefore, the aim of this study was to evaluate serum markers in the pre and postpartum of multiparous dairy cows with clinical mastitis and with health condition in the postpartum period in a semi-extensive management system.Materials, Methods & Results: Thirty-Six Holstein cows were monitored daily during milking until 59 days postpartum and were categorized according to the pre-milking strip cup test into clinical mastitis (mastitis group (MG)) and absence of symptoms (control group (CG)) that were negative to the test, representing the health cows. All cows were reared as one group and maintained in a semi-extensive pasture-based system. Blood samples were collected weekly after morning milking via venipuncture of the coccinea vein into tubes without anticoagulant and grouped for prepartum (-21 to 0 days from calving), early postpartum (0 to 30 days from calving), and late postpartum (30 to 59 days from calving) periods. Milk production was recorded daily. The serum markers albumin, aspartate aminotransferase (AST), phosphorus, gammaglutamyltransferase (GGT) and non-esterified fatty acids (NEFA) were measured. Statistical analyses were performed using SAS®. The cases of clinical mastitis occurred on average at 37.2 ± 4.9 days postpartum. Health cows (CG) had higher milk production compared to the mastitis group (MG) only in the late postpartum period (P < 0.05). There was no difference among groups for albumin and NEFA concentrations in all periods evaluated (P > 0.05).[...](AU)

Serum metabolic markers pre and postpartum in holstein cows according to the mastitis occurrence

Background: Bovine mastitis causes major economic losses for milk producers by reducing the quantity and the quality of the milk or even leading to the complete loss of the mammary gland secretory capacity. During the transition period, dairy cows are susceptible to infectious diseases; therefore, markers that allow early identification of cows in higher risk of developing diseases are especially useful at this time. Therefore, the aim of this study was to evaluate serum markers in the pre and postpartum of multiparous dairy cows with clinical mastitis and with health condition in the postpartum period in a semi-extensive management system.Materials, Methods & Results: Thirty-Six Holstein cows were monitored daily during milking until 59 days postpartum and were categorized according to the pre-milking strip cup test into clinical mastitis (mastitis group (MG)) and absence of symptoms (control group (CG)) that were negative to the test, representing the health cows. All cows were reared as one group and maintained in a semi-extensive pasture-based system. Blood samples were collected weekly after morning milking via venipuncture of the coccinea vein into tubes without anticoagulant and grouped for prepartum (-21 to 0 days from calving), early postpartum (0 to 30 days from calving), and late postpartum (30 to 59 days from calving) periods. Milk production was recorded daily. The serum markers albumin, aspartate aminotransferase (AST), phosphorus, gammaglutamyltransferase (GGT) and non-esterified fatty acids (NEFA) were measured. Statistical analyses were performed using SAS®. The cases of clinical mastitis occurred on average at 37.2 ± 4.9 days postpartum. Health cows (CG) had higher milk production compared to the mastitis group (MG) only in the late postpartum period (P 0.05).[...]

Metabolic and ruminal fluid markers of dairy cows supplemented with a combination of yeast culture and hydrolyzed yeast

Background: In order to reduce the effects of a negative energy balance, some measures have been taken into account in nutritional management during the transition period. The use of yeast, has been a good alternative used to improve the rumen metabolism and helping the adjustment of the microbiotato the new diet. The aim of the study was to evaluate the effects of supplementing a combination of yeast culture and hydrolyzed yeast on the metabolism of dairy cows during the transition period.Materials, Methods & Results:The experiment was conducted in a semi-extensive system, using 20 Holstein cows, divided equally into a control group (CG) and a supplemented group (SG). The SG received 28 g/animal/day of a combination of yeast culture and hydrolyzed yeast from 20 ± 2 days pre-calving until early lactation (18 ± 3 days). Serum concentrations of non-esterified fatty acids (NEFA), albumin and urea were determined at calving, and for three time points during the early postpartum period and three time points during the early lactation period. Regarding energy metabolism, prepartum concentrations of NEFA were higher than the physiological standard in both groups. However, NEFA, albumin and urea decreased during the early postpartum period in the supplemented animals and could be attributed to the yeast in enhancing ruminal microorganisms cellulolytic capacity, increasing fibre digestibility and starch utilization.Discussion: The increased concentration of non-esterified fatty acids (NEFA) due to the mobilization of fat deposits that happens in the transition period, especially in the postpartum period reflects the cows adaptation to the negative energy balance (NEB). The lower concentrations of NEFA observed in the present study could be attributed to the effect of the yeast in enhancing the ruminal microorganisms cellulolytic capacity.[...](AU)

Metabolic and ruminal fluid markers of dairy cows supplemented with a combination of yeast culture and hydrolyzed yeast

Background: In order to reduce the effects of a negative energy balance, some measures have been taken into account in nutritional management during the transition period. The use of yeast, has been a good alternative used to improve the rumen metabolism and helping the adjustment of the microbiotato the new diet. The aim of the study was to evaluate the effects of supplementing a combination of yeast culture and hydrolyzed yeast on the metabolism of dairy cows during the transition period.Materials, Methods & Results:The experiment was conducted in a semi-extensive system, using 20 Holstein cows, divided equally into a control group (CG) and a supplemented group (SG). The SG received 28 g/animal/day of a combination of yeast culture and hydrolyzed yeast from 20 ± 2 days pre-calving until early lactation (18 ± 3 days). Serum concentrations of non-esterified fatty acids (NEFA), albumin and urea were determined at calving, and for three time points during the early postpartum period and three time points during the early lactation period. Regarding energy metabolism, prepartum concentrations of NEFA were higher than the physiological standard in both groups. However, NEFA, albumin and urea decreased during the early postpartum period in the supplemented animals and could be attributed to the yeast in enhancing ruminal microorganisms’ cellulolytic capacity, increasing fibre digestibility and starch utilization.Discussion: The increased concentration of non-esterified fatty acids (NEFA) due to the mobilization of fat deposits that happens in the transition period, especially in the postpartum period reflects the cow’s adaptation to the negative energy balance (NEB). The lower concentrations of NEFA observed in the present study could be attributed to the effect of the yeast in enhancing the ruminal microorganisms’ cellulolytic capacity.[...]

Monensin controlled-release capsules do not change performance and metabolic profile in unchallenged beef cattle

Background: Some additives are able to improve animal performance in growing and finishing periods. Monensin was firstused to control coccidiosis in poultry and was extended to other animals, like ruminants, to act also as a growth promoterand improve cattle performance. In this species, monensin improves the synthesis of propionic acid in the rumen anddecreases methane synthesis and protein degradation, resulting in better performance in protein and energy metabolism.The objective of this study was to evaluate the use of monensin controlled-release capsules on animals grazing Loliummultiflorum intercropped with Trifolium repens on metabolic profile and performance.Materials, Methods & Results: Thirty Hereford cows were randomly distributed into two groups: control (CG) and monensingroup (MG). Monensin was individually administered by controlled-release capsules placed in the rumen through oroesophageal pathway. All animals were identified through earring and kept under the same management condition, grazingon upland pasture mixture of Trifolium repens and Lolium multiflorum. Data from biochemical profile and performancewere collected during 45 days. Blood samples started on the day of monensin controlled-release capsule placement (day0) and continued in periods of 15, 30 and 45 days, after initial placement. Serum levels of albumin, glucose, urea, lactatedehydrogenase (LDH) and aspartate aminotransferase (AST) were evaluated using colorimetric diagnostic kits. In the rumen fluid, pH was measured and protozoa count was performed. All statistical analyses were made using software SAS.Albumin, AST, glucose, LDH and urea were analyzed through MIXED procedure and Tukey-Kramer test was applied forcomparison of means. For average daily gain, the orthogonal polynomials test was applied. Treatments did not differ inBSC, body weight and average daily gain (ADG). None of these performance parameters were significantly affected...(AU)

Monensin controlled-release capsules do not change performance and metabolic profile in unchallenged beef cattle

Background: Some additives are able to improve animal performance in growing and finishing periods. Monensin was firstused to control coccidiosis in poultry and was extended to other animals, like ruminants, to act also as a growth promoterand improve cattle performance. In this species, monensin improves the synthesis of propionic acid in the rumen anddecreases methane synthesis and protein degradation, resulting in better performance in protein and energy metabolism.The objective of this study was to evaluate the use of monensin controlled-release capsules on animals grazing Loliummultiflorum intercropped with Trifolium repens on metabolic profile and performance.Materials, Methods & Results: Thirty Hereford cows were randomly distributed into two groups: control (CG) and monensingroup (MG). Monensin was individually administered by controlled-release capsules placed in the rumen through oroesophageal pathway. All animals were identified through earring and kept under the same management condition, grazingon upland pasture mixture of Trifolium repens and Lolium multiflorum. Data from biochemical profile and performancewere collected during 45 days. Blood samples started on the day of monensin controlled-release capsule placement (day0) and continued in periods of 15, 30 and 45 days, after initial placement. Serum levels of albumin, glucose, urea, lactatedehydrogenase (LDH) and aspartate aminotransferase (AST) were evaluated using colorimetric diagnostic kits. In the rumen fluid, pH was measured and protozoa count was performed. All statistical analyses were made using software SAS.Albumin, AST, glucose, LDH and urea were analyzed through MIXED procedure and Tukey-Kramer test was applied forcomparison of means. For average daily gain, the orthogonal polynomials test was applied. Treatments did not differ inBSC, body weight and average daily gain (ADG). None of these performance parameters were significantly affected...

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.

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.(AU)

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.(AU)