Effect of partially replacing corn with sugar cane molasses on blood parameters and composition of the M. longissimus thoracis of growing pigs / Efeito da substituição parcial do milho por melaço de cana-de-açúcar sobre parâmetros sanguíneos e a composição do músculo longissimus thoracis de suínos em crescimento

The effect of sugar cane molasses, as a partial replacement to corn in the diet, on blood parameters and composition of the M. longissimus thoracis (LT) in growing pigs was explored in this study. Twenty female pigs aged 63 days, and weighing 28.98 ± 3.56 kg, were randomly assigned to either the control or sugar cane molasses treatments. Molasses was included at the 3% level to partially replace corn in their diet. Blood samples were collected at the beginning and end of the experiments. The animals were slaughtered at 110 days of age after 47 days in the experiment, weighing 67.9 ± 5.58 kg, and an LT muscle sample was extracted and evaluated. Each animal was considered an experimental unit. The treatment had no effect on the length and area of the LT muscle. Backfat thickness was reduced when using the sugar cane molasses treatment (5.80 mm) compared to the control treatment (8.90 mm) (P < 0.05). Higher enzyme gamma-glutamyl transferase (GGT) levels were observed in animals of the control treatment (67.10 IU/L) compared to animals treated with the sugar cane molasses treatment (49.90 IU/L) (P < 0.05). Moreover, the proximal composition, fatty acid profile, and quality were not influenced by treatment. Sugar cane molasses, used as an energy source to partially replace corn in the diet of growing pigs at a level of 3%, reduced the backfat thickness of the pig carcass and improved the serum concentration of the enzyme gamma-glutamyl transferase in pigs.(AU)

Neste estudo foi explorado o efeito do melaço de cana-de-açúcar em substituição parcial ao milho na dieta sobre os parâmetros sanguíneos e a composição do músculo longissimus thoracis (LT) de suínos em crescimento. Vinte leitoas com 63 dias de idade, pesando 28,98 ± 3,56 kg foram aleatoriamente distribuídas nos tratamentos controle ou melaço de canade-açúcar. O melaço foi incluído ao nível de 3% em substituição parcial ao milho na dieta. Ao início e ao final do experimento foram coletadas amostras de sangue dos animais. Os animais foram abatidos aos 110 dias de idade após 47 dias de experimento pesando 67,9 ± 5,58 kg e uma amostra do músculo LT foi extraída e avaliada. Cada animal foi considerado uma unidade experimental. Não houve diferença entre os tratamentos sobre o comprimento e a área do músculo LT. A espessura de toucinho foi reduzida ao utilizar o tratamento melaço de cana-de-açúcar (5,80 mm) em relação ao tratamento controle (8,90 mm) (P < 0,05). Níveis mais elevados da enzima gama-glutamil transferase (GGT) foram observados nos animais do tratamento controle (67,10 UI/L) em comparação aos animais do tratamento melaço de cana-de-açucar (49,90 UI/L) (P < 0,05). A composição proximal e o perfil e qualidade dos ácidos graxos não foram influenciados pelo tratamento. O melaço de cana-de-açúcar utilizado como fonte energética em substituição parcial ao milho na dieta de suínos em crescimento ao nível de 3% reduziu a espessura de toucinho da carcaça de suínos e melhorou a concentração sérica da enzima gama-glutamil transferase de suínos.(AU)

Socioeconomic profile of producers and dairy technological of farms in the southern mesoregion of Santa Catarina / Perfil socioeconômico dos produtores e tecnológico de propriedades leiteiras da mesorregião sul de Santa Catarina

This study characterized the socioeconomic profile of milk producers and dairy technological of farms in the southern mesoregion of Santa Catarina. Following a 6.5% sampling of total farms by municipality, 95% confidence level, 5% sampling error, and group heterogeneity, data were collected from 308 farms, 22 of which were excluded due to insufficient data. The farmers were selected randomly, and information extracted from an electronic form, addressing social, economic, technical and technological issues. The data were analyzed using factor, cluster, and discriminant analysis. As farms with the main activity of dairy farming, they have an average area of 20.79 hectares and a production of 12.18 liters per animal per day. I n the factor analysis, the first factor was related to the area and productivity of farms and the second factor to sanitary control and the feed variety of the animals. The cluster analysis formed three clusters; the first and the second were composed of larger farms and areas, and the other consisted of smaller farms, the latter involving more producers. As farms are characterized by low production, there is clearly a deficiency in technical support for producers.(AU)

O objetivo desse estudo foi caracterizar o perfil socioeconômico dos produtores de leite e o tecnológico de propriedades leiteiras da mesorregião sul do estado de Santa Catarina. Seguindo uma amostragem de 6,5% sobre o total de propriedades por município, nível de confiança de 95%, erro amostral de 5% e heterogeneidade no grupo, foram coletados dados de 308 propriedades, sendo que 22 delas foram excluídas por apresentarem dados insuficientes. Os produtores foram selecionados de forma aleatória e as informações extraídas através de um formulário eletrônico, abarcando questões sociais, econômicas, técnicas e tecnológicas. Os dados foram analisados pelas análises fatorial, de agrupamento e discriminante. As propriedades apresentaram como principal atividade a bovinocultura leiteira, possuem área média de 20,79 hectares e uma produção de 12,18 litros por animal por dia. Na análise fatorial, o primeiro fator esteve relacionado com a área e produtividade das propriedades e o segundo fator com controle sanitário e a variedade alimentar dos animais. A análise de agrupamento formou três clusters, o primeiro e o segundo, compostos por propriedades com áreas e produtividade maiores e outro constituído por propriedades de menor porte, sendo esse último o que envolveu mais produtores. As propriedades são caracterizadas por baixa produção, existindo claramente uma deficiência no acompanhamento técnico aos produtores.(AU)

In vitro and in vivo parameters for identification of landrace pigs with low reproductive performance / Parâmetros in vitro e in vivo para detecção de machos suínos Landrace com baixo desempenho reprodutivo

In pig farming, measurements of production parameters play a fundamental role in the success of the activity. Minimal differences in fertility between breeders can lead to less reproductive efficiency and, less productivity. However, assessing the fertility of each male and the early identification of subfertile males is a difficult task to be performed. Thus, the aim of this study was to evaluate the use of in vitro and in vivo parameters in the identification of subfertile males of the Landrace breed, aiming to collaborate with genetic improvement programs, routine optimization in the Genetic Diffusion Units (GDUs) and the results of performance. In experiment 1, an approach to identify males with subfertility was evaluated based on retrospective data. For this, the results (averages of birth rates, number of total births and average percentages of female and male piglets per litter) were evaluated for a total of 996 matings and 847 parturitions. The inseminations came from ejaculates of 32 males, who had at least 19 females inseminated with homospermic doses in the concentration of 2.5 x 109 total sperm from the same male. As for the birth rate (BR), an average of 85.47% ± 6.05 was observed with a group of median males, seven males that stood out and one individual (M32) with a performance of 58.06% ± 9.0. For the total number of piglets born (PB) the average was 13.41 ± 0.56, with three males with better performance and one (M32) with very poor performance (8.62 ± 0.59). In experiment 2, it was verified whether evaluations of inseminating doses (ID) of semen in vitro (motility and sperm morphology) after 96 hours of storage had correlations with fertility in vivo, which can be used to identify subfertile males. The evaluations were performed on 30 ejaculates regarding the means of BR and PB, considering only those who had at least 7 females inseminated. There were no correlations between the motility assessments and semen morphological changes and the reproductive parameters evaluated. The results obtained in vivo, referring to BR and PB, demonstrated that it was possible to identify differences between males, the individual (M32) had the worst results for the percentages of BR and PB. It is concluded that there are males of high and low fertility and that only the in vitro analyzes carried out in this study are not enough to categorize them, however, the evaluation of retrospective data was efficient for this purpose.(AU)

Na suinocultura moderna, as mensurações de parâmetros de produção têm papel fundamental para o sucesso da atividade. No entanto, a avaliação da fertilidade de cada macho e a identificação precoce de machos subférteis é uma tarefa difícil de ser realizada. O objetivo deste estudo foi avaliar a utilização de parâmetros in vivo e in vitro na identificação de machos subférteis da raça Landrace, visando colaborar com os programas de melhoramento genético, otimização da rotina nas Unidade de Difusão Genética (UDGs) e dos resultados a campo. No experimento 1, foi proposta uma abordagem de identificação dos machos subférteis tendo como base dados retrospectivos. Para isso, foram avaliados os resultados (médias das taxas de parto, número de nascidos totais e média das porcentagens de leitões fêmeas e machos por leitegada) de um total de 996 coberturas e 847 partos. As inseminações foram oriundas de ejaculados de 32 machos, que tiveram ao menos 19 fêmeas cobertas com doses homospérmicas na concentração de 2,5 x 109 de espermatozoides totais e obrigatoriamente do mesmo macho. Quanto a taxa de parto (TP) obtivemos uma média de 85,47% ± 6,05 e observou-se um grupo de machos medianos, sete machos que se destacaram positivamente e um indivíduo (M32) com um desempenho 58,06 ± 9,0. Para número de leitões nascidos totais (NT) obtivemos uma média de 13,41 ± 0,56 e notou-se três machos com melhor desempenho e um (M32) com péssimo desempenho (8,62 ± 0,59). No experimento 2, foi verificado se as avaliações das doses inseminantes (DI) de sêmen in vitro (motilidade e morfologia espermática) após 96 horas de armazenamento apresentaram correlação com a fertilidade in vivo. As avaliações foram realizadas em 30 ejaculados quanto às médias de TP e NT, considerando apenas ejaculados que tiveram ao menos 7 fêmeas inseminadas. Não foram verificadas correlações entre as avaliações de motilidade e alterações morfológicas do sêmen com os parâmetros produtivos avaliados. Os resultados obtidos in vivo, referentes a TP e NT, mostrou que foi possível identificar diferença entre os machos, onde o indivíduo (M32) apresentou os piores resultados para as porcentagens de TP e NT. Desta forma, pode-se concluir que existem machos de alta e baixa fertilidade e que somente as análises in vitro realizadas neste estudo não são suficientes para categorizá-los, no entanto, a avaliação de dados retrospectivos foi eficiente para esta finalidade.(AU)

Distribution of cysts holding Ascocotyle (Phagicola) longa metacercariae in tissues and organs of mugilid / Distribuição de cistos contendo metacercárias de Ascocotyle (Phagicola) longa em tecidos e órgãos de mugilídeos

Ascocotyle (Phagicola) longa is an etiological agent of human phagicolosis. Mugilids are the second intermediate host, the first being Heleobia australis, and mugilids predatory birds and mammals are its definitive hosts. The occurrence of cysts holding A. longa metacercariae is described in mugilids with a prevalence of up to 100%. The wide geographical distribution of A. longa and its intermediate hosts coupled with the rise in the consumption of raw or poorly cooked fish may elevate the risk of human infection. Therefore, in this study, we aimed to verify the distribution pattern of cysts holding A. longa in mugilids. The tissue and organ samples of these fish were processed in a domestic blender and examined under a stereoscopic microscope to identify the cysts holding the digenetic metacercariae. Of the 24 (100%) fish samples that were analyzed, 12 of Mugil curema and 12 of Mugil liza possessed cysts holding A. longa metacercariae. Digenetic cysts were identified to be present in the gills, heart, stomach, liver, intestines, mesentery, and muscular tissues collected from M. curema and M. liza. Conclusively, in M. curema, the cysts holding A. longa metacercariae were found to be distributed randomly throughout the fish body in almost every tissue and organ that was examined.(AU)

Ascocotyle (Phagicola) longa é o agente etiológico da fagicolose humana. Os mugilídeos são os segundos hospedeiros intermediários. O primeiro é Heleobia australis e pássaros e mamíferos predadores de mugilídeos, os hospedeiros definitivos. A ocorrência de cistos contendo metacercárias de A. longa é descrita em mugilídeos, com até 100% de prevalência. A ampla distribuição geográfica de A. longa e seus hospedeiros intermediários, acompanhado do aumento do consumo de peixe cru ou mal cozido, pode aumentar o risco de infecção humana, portanto o objetivo do presente estudo foi verificar o padrão de distribuição de cistos, contendo metacercárias de A. longa, em mugilídeos. Amostras de tecidos e órgãos desses peixes foram processadas em liquidificador doméstico e observadas em microscópio estereoscópico à procura de cistos contendo metacercárias do digenético. Todos os 24 (100%) mugilídeos, 12 Mugil curema e 12 Mugil liza examinados apresentaram cistos contendo metacercária de A. longa. Foram observados cistos do digenético nas brânquias, coração, estômago, fígado, intestino, mesentério e tecido muscular de M. curema e de M. liza. Em M. curema, os cistos contendo metacercárias de A. longa estão distribuídos de forma aleatória por praticamente todos os tecidos e órgãos dos mugilídeos examinados.(AU)

Distribution of cysts holding Ascocotyle (Phagicola) longa metacercariae in tissues and organs of mugilid / Distribuição de cistos contendo metacercárias de Ascocotyle (Phagicola) longa em tecidos e órgãos de mugilídeos

Abstract Ascocotyle (Phagicola) longa is an etiological agent of human phagicolosis. Mugilids are the second intermediate host, the first being Heleobia australis, and mugilids predatory birds and mammals are its definitive hosts. The occurrence of cysts holding A. longa metacercariae is described in mugilids with a prevalence of up to 100%. The wide geographical distribution of A. longa and its intermediate hosts coupled with the rise in the consumption of raw or poorly cooked fish may elevate the risk of human infection. Therefore, in this study, we aimed to verify the distribution pattern of cysts holding A. longa in mugilids. The tissue and organ samples of these fish were processed in a domestic blender and examined under a stereoscopic microscope to identify the cysts holding the digenetic metacercariae. Of the 24 (100%) fish samples that were analyzed, 12 of Mugil curema and 12 of Mugil liza possessed cysts holding A. longa metacercariae. Digenetic cysts were identified to be present in the gills, heart, stomach, liver, intestines, mesentery, and muscular tissues collected from M. curema and M. liza. Conclusively, in M. curema, the cysts holding A. longa metacercariae were found to be distributed randomly throughout the fish body in almost every tissue and organ that was examined.

Resumo Ascocotyle (Phagicola) longa é o agente etiológico da fagicolose humana. Os mugilídeos são os segundos hospedeiros intermediários. O primeiro é Heleobia australis e pássaros e mamíferos predadores de mugilídeos, os hospedeiros definitivos. A ocorrência de cistos contendo metacercárias de A. longa é descrita em mugilídeos, com até 100% de prevalência. A ampla distribuição geográfica de A. longa e seus hospedeiros intermediários, acompanhado do aumento do consumo de peixe cru ou mal cozido, pode aumentar o risco de infecção humana, portanto o objetivo do presente estudo foi verificar o padrão de distribuição de cistos, contendo metacercárias de A. longa, em mugilídeos. Amostras de tecidos e órgãos desses peixes foram processadas em liquidificador doméstico e observadas em microscópio estereoscópico à procura de cistos contendo metacercárias do digenético. Todos os 24 (100%) mugilídeos, 12 Mugil curema e 12 Mugil liza examinados apresentaram cistos contendo metacercária de A. longa. Foram observados cistos do digenético nas brânquias, coração, estômago, fígado, intestino, mesentério e tecido muscular de M. curema e de M. liza. Em M. curema, os cistos contendo metacercárias de A. longa estão distribuídos de forma aleatória por praticamente todos os tecidos e órgãos dos mugilídeos examinados.

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).[...]

Calcium and magnesium urinary excretion in dairy cows with different fee of glucose metabolization / Excreção urinária de cálcio e magnésio em vacas leiteiras com diferentes taxas de metabolização de glicose

Background: The post-partum period in dairy cows is accompanied by a low glucose metabolism in adipose tissue and skeletal muscle tissue, being glucose conducted to the milk production. In humans, low glucose metabolism is associated with metabolic syndromes, the high glucose levels reduce tubular reabsorption of Magnesium (Mg) and Calcium (Ca), leading to hypomagnesemia and hypocalcemia. These minerals are important to the dairy cow, as their decrease leads to diseases. The aim of this study was to evaluate the relationship between glucose metabolism rate with the urinary excretion of Ca and Mg in multiparous dairy cows during the post-partum period.Materials, Methods & Results: Twenty dairy cows were used from a commercial farm southern Brazil, in the semi-extensive system. Glucose tolerance tests were performed (TTG) on day 9 relative to calving. The cows were categorized into three groups according to the glucose metabolism rate (area under the glucose curve, glucose half-life and glucose consumption rate): High Glucose Metabolization (GA); Intermediate Glucose Metabolizing (GI); and Low Glucose Metabolization (GL). Blood and urine samples were collected on days 0, + 3, + 6, + 9, +16 and +23 in relation to calving for to determine the levels of Ca, Mg, insulin (Ins), non-esterified fatty acids (NEFA) and Glu. In urine was evaluated the excretion of Ca and Mg. The cows were milked twice a day (at 3:00 a.m. and 3:00 p.m.) and the milk yield (kg/cow) was recorded daily and averages were generated every five days from day 15 to day 60 postpartum. The statistical analyses were performed with the MIXED procedure to assess the main effect of group, time (in days) and their interaction by using version 9.2 SAS software.[...]

Calcium and magnesium urinary excretion in dairy cows with different fee of glucose metabolization / Excreção urinária de cálcio e magnésio em vacas leiteiras com diferentes taxas de metabolização de glicose

Background: The post-partum period in dairy cows is accompanied by a low glucose metabolism in adipose tissue and skeletal muscle tissue, being glucose conducted to the milk production. In humans, low glucose metabolism is associated with metabolic syndromes, the high glucose levels reduce tubular reabsorption of Magnesium (Mg) and Calcium (Ca), leading to hypomagnesemia and hypocalcemia. These minerals are important to the dairy cow, as their decrease leads to diseases. The aim of this study was to evaluate the relationship between glucose metabolism rate with the urinary excretion of Ca and Mg in multiparous dairy cows during the post-partum period.Materials, Methods & Results: Twenty dairy cows were used from a commercial farm southern Brazil, in the semi-extensive system. Glucose tolerance tests were performed (TTG) on day 9 relative to calving. The cows were categorized into three groups according to the glucose metabolism rate (area under the glucose curve, glucose half-life and glucose consumption rate): High Glucose Metabolization (GA); Intermediate Glucose Metabolizing (GI); and Low Glucose Metabolization (GL). Blood and urine samples were collected on days 0, + 3, + 6, + 9, +16 and +23 in relation to calving for to determine the levels of Ca, Mg, insulin (Ins), non-esterified fatty acids (NEFA) and Glu. In urine was evaluated the excretion of Ca and Mg. The cows were milked twice a day (at 3:00 a.m. and 3:00 p.m.) and the milk yield (kg/cow) was recorded daily and averages were generated every five days from day 15 to day 60 postpartum. The statistical analyses were performed with the MIXED procedure to assess the main effect of group, time (in days) and their interaction by using version 9.2 SAS software.[...](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). There was no difference among groups for albumin and NEFA concentrations in all periods evaluated (P > 0.05).[...](AU)

Paraoxonase activity in the serum of peripartum dairy cows with different placental lactogen concentrations / Atividade sérica de Paraoxanase durante o periparto de vacas leiteiras com diferentes concentrações de Lactogênio Placentário

The action of the bovine placental lactogen (bPL) hormone on maternal metabolism is still poorly known. Some markers, such as the acute phase protein paraoxonase (PON1), are used as indicators of liver function and help to determine the metabolic condition during the transition period in dairy cows. The aim of this study was to evaluate the activity of paraoxonase (PON1) in the serum of peripartum dairy cows with different levels of bPL. Based on the plasma bPL concentration, 18 cows were divided equally into three groups: LOW ( < 2,68 ng bPL mL-1), MEDIUM (2,682,80 ng bPL mL-1), and HIGH ( > 2,80 ng bPL mL-1). The experiment was conducted between 21 days prepartum and 28 days postpartum. Serum samples were collected during the experiment for the determination of bPL concentrations and PON1 activity. The bPL concentration was significantly different between the experimental groups (P ≤ 0,0001) and the days of serum collection (P ≤ 0,0001). In the prepartum dairy cows, the PON1 levels were different between the groups (P ≤ 0,05) and the days of serum collection (P ≤ 0,05). Cows with high bPL concentration had lower serum PON1 activity (P ≤ 0,05), while cows with low hormone levels had higher enzyme activity (P ≤ 0,05). In the postpartum period, there was a significant difference between the days of serum collection (P ≤ 0,0001) and the interaction between groups and collections(P ≤ 0,01). The group with high concentrations of bPL had lower levels of PON1 (P ≤ 0,01), while thegroup with low bPL maintained higher concentrations of PON1 (P ≤ 0,01). It was concluded that thecows with higher concentrations of bPL in the prepartum period present a reduction in the serum activityof the PON1 enzyme during the peripartum period.(AU)

A ação do hormônio Lactogênio Placentário Bovino (bLP) no metabolismo materno ainda é poucoconhecida. Alguns marcadores, como a proteína de fase aguda Paraoxanase (PON1), são utilizadoscomo indicadores da função hepática auxiliando na determinação da condição metabólica no período de transição em vacas leiteiras. O objetivo deste trabalho foi avaliar a atividade sérica de PON1 duranteo periparto em vacas leiteiras com diferentes níveis de bLP. As vacas foram divididas em três gruposde acordo com as concentrações plasmáticas de bLP, em que BAIXO < 2,68 ng mL-1 (n=6), MÉDIO> 2,68 ng mL-1 e < 2,80 ng mL-1 (n=6) e ALTO > 2,80 ng mL-1 (n=6). O período experimental ocorreuentre os 21 dias pré-parto e 28 dias pós-parto. Amostras de soro foram coletadas para a determinaçãodas concentrações de bLP e atividade sérica de PON1. Houve diferença entre os três grupos (P ≤ 0,0001)de acordo com as concentrações de bLP, assim como entre os dias coletados (P ≤ 0,0001). No pré-parto,os níveis de PON1 apresentaram diferença entre grupos (P ≤ 0,05) e coletas (P ≤ 0,05). Vacas com altaconcentração de bLP apresentaram menor atividade sérica de PON1 (P ≤ 0,05), enquanto vacas combaixos níveis do hormônio obtiveram maior atividade da enzima (P ≤ 0,05). No pós-parto não houvediferença entre grupos (P ≥ 0,10), houve diferença entre os dias coletados (P ≤ 0,0001) e interação entregrupos e coletas (P ≤ 0,01). O grupo com altas concentrações de bLP apresentou menores níveis dePON1 (P ≤ 0,01), enquanto vacas do grupo com baixo bLP mantiveram maiores concentrações de PON1(P ≤ 0,01). Conclui-se que, vacas com maiores concentrações de bLP no período pré-parto apresentamredução na atividade sérica da enzima PON1 durante o período periparto.(AU)

Lesões associadas à laminite subclínica e exame radiográfico digital em vacas da raça holandês no período transicional / Lesions associated with subclinical laminitis and digital radiographic exam in holstein cows in the transitional period

Subclinical laminitis has been responsible for economic losses in dairy industry; thus, its diagnostic    is very important to prevent negative responses to milk production industry. The aim of this study  was to identify lesions associated with subclinical laminitis during the transition period with presence or absence of radiographic signs linked to this disease in Holstein cows. The cows were evaluated during the transition period and categorized into two groups (with and without laminitis) according to the lesions associated with this subclinical disease. The radiological dynamic was performed in two target points during the transition period (prepartum and postpartum), with the objective of determining capsular position possible alterations and third phalanx bone degeneration (F3). There was no effect of the presence of lesions associated with subclinical laminitis regarding the position of the third phalanx to the hoof wall (p>0.05). Significant radiographic angular differences (p 0.05) between F3 and the hoof wall were observed between the lateral and medial nails of the same digit, but not within groups (p>0.05). Overall, this study did not show radiographic signs of phalangeal misalignment in the hoof of dairy cows with lesions associated with subclinical laminitis during the transition period.

A laminite subclínica é responsável por grandes prejuízos na pecuária leiteira, sendo o seu diagnóstico de grande relevância para evitar reflexos negativos na produção. Portanto, o objetivo deste trabalho foi relacionar lesões associadas à laminite subclínica no período de transição de vacas da raça Holandês com a ocorrência ou não de sinais radiográficos vinculados a essa enfermidade. As vacas foram avaliadas durante o período de transição e divididas em dois grupos (com e sem sinais de laminite subclínica) de acordo com as lesões associadas a essa enfermidade subclínica. A dinâmica radiológica foi realizada em dois momentos durante o período de transição, com o propósito de determinar possíveis alterações de posicionamento capsular e degeneração óssea da terceira falange (F3). Não foram observados efeitos da presença de lesões associadas à laminite subclínica frente ao posicionamento da terceira falange      à cápsula do casco (p>0,05). Diferenças radiográficas significativas (p 0,05) angulares entre a F3 e      a cápsula do casco foram observadas entre as unhas lateral e medial do mesmo dígito, mas não entre grupos (p>0,05). Assim, neste estudo, vacas leiteiras no período de transição com lesões associadas      à laminite subclínica não apresentaram sinais radiográficos de desalinhamento falangeano ao estojo córneo digital.

Lesões associadas à laminite subclínica e exame radiográfico digital em vacas da raça holandês no período transicional / Lesions associated with subclinical laminitis and digital radiographic exam in holstein cows in the transitional period

Subclinical laminitis has been responsible for economic losses in dairy industry; thus, its diagnostic    is very important to prevent negative responses to milk production industry. The aim of this study  was to identify lesions associated with subclinical laminitis during the transition period with presence or absence of radiographic signs linked to this disease in Holstein cows. The cows were evaluated during the transition period and categorized into two groups (with and without laminitis) according to the lesions associated with this subclinical disease. The radiological dynamic was performed in two target points during the transition period (prepartum and postpartum), with the objective of determining capsular position possible alterations and third phalanx bone degeneration (F3). There was no effect of the presence of lesions associated with subclinical laminitis regarding the position of the third phalanx to the hoof wall (p>0.05). Significant radiographic angular differences (p 0.05) between F3 and the hoof wall were observed between the lateral and medial nails of the same digit, but not within groups (p>0.05). Overall, this study did not show radiographic signs of phalangeal misalignment in the hoof of dairy cows with lesions associated with subclinical laminitis during the transition period.(AU)

A laminite subclínica é responsável por grandes prejuízos na pecuária leiteira, sendo o seu diagnóstico de grande relevância para evitar reflexos negativos na produção. Portanto, o objetivo deste trabalho foi relacionar lesões associadas à laminite subclínica no período de transição de vacas da raça Holandês com a ocorrência ou não de sinais radiográficos vinculados a essa enfermidade. As vacas foram avaliadas durante o período de transição e divididas em dois grupos (com e sem sinais de laminite subclínica) de acordo com as lesões associadas a essa enfermidade subclínica. A dinâmica radiológica foi realizada em dois momentos durante o período de transição, com o propósito de determinar possíveis alterações de posicionamento capsular e degeneração óssea da terceira falange (F3). Não foram observados efeitos da presença de lesões associadas à laminite subclínica frente ao posicionamento da terceira falange      à cápsula do casco (p>0,05). Diferenças radiográficas significativas (p 0,05) angulares entre a F3 e      a cápsula do casco foram observadas entre as unhas lateral e medial do mesmo dígito, mas não entre grupos (p>0,05). Assim, neste estudo, vacas leiteiras no período de transição com lesões associadas      à laminite subclínica não apresentaram sinais radiográficos de desalinhamento falangeano ao estojo córneo digital.(AU)

LESÕES ASSOCIADAS À LAMINITE SUBCLÍNICA E EXAME RADIOGRÁFICO DIGITAL EM VACAS DA RAÇA HOLANDÊS NO PERÍODO TRANSICIONAL

Abstract Subclinical laminitis has been responsible for economic losses in dairy industry; thus, its diagnostic is very important to prevent negative responses to milk production industry. The aim of this study was to identify lesions associated with subclinical laminitis during the transition period with presence or absence of radiographic signs linked to this disease in Holstein cows. The cows were evaluated during the transition period and categorized into two groups (with and without laminitis) according to the lesions associated with this subclinical disease. The radiological dynamic was performed in two target points during the transition period (prepartum and postpartum), with the objective of determining capsular position possible alterations and third phalanx bone degeneration (F3). There was no effect of the presence of lesions associated with subclinical laminitis regarding the position of the third phalanx to the hoof wall (p>0.05). Significant radiographic angular differences (p 0.05) between F3 and the hoof wall were observed between the lateral and medial nails of the same digit, but not within groups (p>0.05). Overall, this study did not show radiographic signs of phalangeal misalignment in the hoof of dairy cows with lesions associated with subclinical laminitis during the transition period.

Resumo A laminite subclínica é responsável por grandes prejuízos na pecuária leiteira, sendo o seu diagnóstico de grande relevância para evitar reflexos negativos na produção. Portanto, o objetivo deste trabalho foi relacionar lesões associadas à laminite subclínica no período de transição de vacas da raça Holandês com a ocorrência ou não de sinais radiográficos vinculados a essa enfermidade. As vacas foram avaliadas durante o período de transição e divididas em dois grupos (com e sem sinais de laminite subclínica) de acordo com as lesões associadas a essa enfermidade subclínica. A dinâmica radiológica foi realizada em dois momentos durante o período de transição, com o propósito de determinar possíveis alterações de posicionamento capsular e degeneração óssea da terceira falange (F3). Não foram observados efeitos da presença de lesões associadas à laminite subclínica frente ao posicionamento da terceira falange à cápsula do casco (p>0,05). Diferenças radiográficas significativas (p 0,05) angulares entre a F3 e a cápsula do casco foram observadas entre as unhas lateral e medial do mesmo dígito, mas não entre grupos (p>0,05). Assim, neste estudo, vacas leiteiras no período de transição com lesões associadas à laminite subclínica não apresentaram sinais radiográficos de desalinhamento falangeano ao estojo córneo digital.

Evaluation of the diagnosis of perihepatitis in swine after slaughter and relationship with the levels of liver enzymes / Avaliação do diagnóstico de perihepatite em suínos após o abate e sua relação com os níveis de enzimas hepáticas

The liver is an organ with a differential value on the market. However, due to its metabolic functions it is susceptible to various types of alterations, including a large rate of disposal by perihepatitis. The aim of this study was to evaluate the sensitivity and specificity of the diagnosis of perihepatitis by the Federal Inspection Service (FIS), according to histopathological examination and correlate these findings with plasmatic concentrations of AST and GGT. One hundred and fifty four culled sows of the Landrace breed were used. Slaughter was performed by the method of desensitization by electrical stimulation and subsequent exsanguination. Then 5 mL of whole blood was collected to evaluate concentrations of GGT and AST. During evisceration, liver condition was assessed by visual inspection and classified as good or condemned by perihepatitis. Also, fragments of the liver were collected to histopathologic examination. The alterations in the liver parenchyma were classified as degenerative, inflammatory or reparative. The alterations found in liver tissues, considered as perihepatitis by visual inspection, were often due to fibrosis, fatty degeneration or mild hepatitis. The serum concentrations of GGT were high. Moreover, it concentrations were higher in livers with lesions of inflammatory and degenerative nature when compared to livers without injuries (p 0.05).However, the same was not observed for AST concentrations (p>0.05). Concluding, the perihepatitis diagnosis from the FIS showed low specificity and sensitivity, and the enzyme GGT was a good indicator of liver injuries in swine.(AU)

O fígado é um órgão de valor comercial diferenciado, porém, em virtude das suas funções metabólicas, é susceptível a diversos tipos de alterações, destacando-se um grande número de descartes por perihepatite. O objetivo deste estudo foi avaliar a sensibilidade e especificidade do diagnóstico desta alteração pelo Serviço de Inspeção Federal (SIF), segundo exame histopatológico, e correlacionar estes achados com os níveis plasmáticos de AST e GGT. Foram utilizadas 154 matrizes da raça Landrace de descarte. O abate foi feito com o método de insensibilização por estímulo elétrico e posterior sangria, sendo coletados 5 mL de sangue total, para determinação dos níveis de GGT e AST. Durante a evisceração, foi avaliada a condição do fígado pela inspeção sanitária classificando-o como liberado ou condenado por perihepatite. Fragmentos de fígado foram colhidos, para fins de comparações histopatológicas. Na presença de alteração do parênquima hepático, essa foi classificada em degenerativa, inflamatória ou reparativa. Os resultados do estudo demonstraram que as lesões encontradas no tecido hepático, consideradas como perihepatite pela inspeção sanitária, tratavam-se muitas vezes de alterações hepáticas como fibroses, degeneração gordurosa ou hepatites discretas. Os níveis de GGT se apresentaram elevados, sendo exacerbados em lesões de caráter inflamatório e degenerativo, em comparação com animais sem lesão hepática (p<0,05), o que não foi observado para os níveis de AST (p>0,05). Assim, observou-se que o diagnóstico de perihepatite pelo SIF apresentou baixa especificidade e sensibilidade, e que a enzima GGT é um bom indicador de lesões hepáticas em suínos.(AU)

Metabolic assessment of the use of probiotic or monensin in lambs kept in semi-confined conditions / Avaliação metabólica do uso de probiótico ou monensina em cordeiros mantidos em semi-confinamento

The objective of this study was to verify probiotics and monensin effects on metabolic parameters in weaning lambs. In the experiment 1, thirty lambs divided in three groups were fed during 6 weeks. The lambs were enrolled in one of the following treatments: GC1: as a control, GB1: Bacillus cereus var. toyoi (1x106 spores/g) and GS1: Saccharomyces boulardii (1x106 viable cells/g). In the experiment 2, thirty lambs divided in three groups were fed during 8 weeks. The treatments consisted in GC2: as a control, GM2: monensin (500g/t) and GS2: Saccharomyces boulardii (1x106viable cells/g). In both experiments blood samples were collected weekly aiming to measure metabolic parameters as glucose, triacylglycerol (TAG), cholesterol, albumin, urea, aspartate amino transferase (AST), creatinine kinase (CK) and gamma glutamil transferase (GGT). The results from experiment 1 demonstrated that GS1 had greater (P<0.05) concentrations of albumin and urea during the adaptation period. In the post-adaption period the GC1 demonstrated increased (P<0.05) concentrations of cholesterol, albumin and AST activity, in contrast, reduced (P<0.05) concentrations of glucose, urea and CK in comparison to GS1. However, during experiment two throughout the adaptation period the GS2 had greater (P<0.05) concentrations for albumin and urea. The GM2 had greater (P<0.05) concentrations for TAG and lower (P<0.05) for glucose and CK activity. During the post-adaption period the GS2 showed the lowest (P<0.05) concentrations for cholesterol and GGT activity, GC2 had greater (P<0.05) levels of albumin and AST activity as well as lower concentrations for urea. The GM2 had greater levels for GGT activity and lower levels for CK activity. Therefore, it is concluded that protein metabolism in lambs has better performance when Saccharomyces boulardii is added in the ration during the adaptation period.(AU)

O objetivo do estudo foi verificar o efeito de probióticos e monensina sobre parâmetros metabólicos de cordeiros desmamados. No primeiro experimento foram utilizados 30 cordeiros, alimentados durante 6 semanas, de acordo com os seguintes tratamentos. GC1: Controle (sem aditivo), GB1: Bacillus cereus var. toyoi (1x106 esporos/g) e GS1: Saccharomyces boulardii (1x106 células viáveis/g). No segundo experimento foram utilizados 30 cordeiros, alimentados durante 8 semanas divididos em três tratamentos: GC2: Controle (sem aditivo), GM2: Monensina sódica (500g/t) e o GS2: Saccharomyces boulardii (1x106 células viáveis/gr). Semanalmente foram coletas amostras de sangue. Em ambos os experimentos foram avaliados: glucose, triacilglicerídeos (TAG), colesterol, albumina, ureia, aspartato amino transferase (AST), creatinina quinase (CK) e gama glutamil transferase (GGT). O GS1 obteve maiores concentrações de albumina e ureia (P<0,01), quando comparado aos demais grupos, no período adaptativo. O GC1 demonstrou maiores concentrações de colesterol, albumina e atividade de AST (P<0,05), e menores de glucose, ureia e atividade de CK (P<0,05), quando comparadas ao GS1, no período pós-adaptativo. No experimento dois durante o período adaptativo o GS2 obteve maiores concentrações de albumina e ureia (P<0,01), quando comparado aos demais. O GM2 obteve maiores concentrações de TAG (P<0,01) e menores de glucose e atividade de CK (P<0,05), quando comparado aos demais, no período adaptativo. O GS2 obteve menores concentrações de colesterol e atividade de GGT (P<0,05), quando comparado com os demais, no período pós-adaptativo. O GC2 obteve maiores concentração de albumina e atividade de AST (P<0,01), e menores de ureia (P<0,05), quando comparados com os demais, no período pós-adaptativo. O GM2 obteve maior atividade de GGT (P<0,05) e menor atividade de CK (P<0,05), quando comparado com os demais, no período pós-adaptativo. .(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...(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...

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.(AU)

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.(AU)

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)

Composição do leite, pH do fluído ruminal e perfil metabólico de vacas leiteiras suplementadas com uréia de liberação lenta / Milk Composition, Ruminal pH and Metabolic Parameters of Dairy Cows Supplemented with Slow-Release Urea

Background: The protein supplements can represent up to 50% of the costs in the concentrated fraction of the diet in dairy cows. A possible alternative that meets the requirements regarding protein levels and can reduce the costs are the nonprotein nitrogen (NPN) supplementst. For these reasons, this strategy it is widely used in low milk production systems, where cost of production has a higher impact. In this scenario the use of NPN aims to increase production without altering the economic balance of the system. Recently, a supplement consisting of urea coated with a biodegradable polymer was developed. This system promotes the controlled release of urea that can reach up 36 h after ingestion. The aim of this study was to evaluate the effects of feeding slow release urea formula on the composition and milk production, metabolic parameters and pH of the ruminal fluid of dairy cows. Materials, Methods & Results: This study was conducted over a period of 60 days, using 20 multiparous cows with 90 ± 18 days in milk. The animals were divided into two groups according to the type of NPN: 1) conventional urea (CG) and 2) slow release urea (SRG). Each group was composed of six Holstein cows (average body weight 528.7 ± 51.9 kg) and four Jersey cows (average body weight 389.3 ± 33.3 kg). Cows in the CG received a diet containing 80g of conventional urea/cow/day, and SRG cows were fed a diet containing 88g of slow release urea/cow/day, both diets were kept isocaloric and isonitrogenous between groups. Weekly weighing and sampling was performed for evaluation of milk production, composition, somatic cell count (SCC) and urea levels in milk. Blood samples were taken weekly to measure the levels of γ-glutaryl transferase, urea, and albumin. Biweekly ruminocentese was performed for collection of ruminal fl uid and pH measurement. Among the metabolites examined the only difference between groups was for milk urea, with SRG having higher milk urea than CG cows (P < 0.04). No differences were observed for milk yield corrected to 3.5% fat, milk composition and ruminal pH (P > 0.05). However, a breed effect was observed, with the Jersey cows having the highest milk fat content (P < 0.04; 4.4 ± 0.27% vs 3.6 ± 0.22%), total solids (P < 0.01; 13.22 ± 0.43% vs 11.74 ± 0.35%) and urea (P < 0.002; 52.31 ± 1.43 mg/dL vs. 46.12 ± 1.17 mg/dL) compared to Holstein cows, respectively. Discussion: Milk production was not different between groups supplemented with different sources of NPN, similar to the described by other studies. Previous studies that found differences in milk production were probably due to the with drawal of the true protein fraction of the diet, which allowed the synchronization of the degradation of carbohydrates and nitrogen release by the slow release formula. Serum urea concentration remained within the physiological levels for both groups, demonstrating that the diet was maintained in equilibrium. The enzyme γ-glutaryl transferase did not show any difference between groups, indicating that no systemic damage occurred. The results of this experiment indicate that supplementation with slow release urea at 1.8% of the dry matter intake did not influence the parameters studied, behaving like conventional urea. Thus the slow release urea can be used as an alternative protein source without damage to the metabolism, however for low producing dairy systems, characterized as semi-skilled, no benefits are observed since it has a higher cost.