Nutrient intake, digestibility and ruminal characteristics of lambs supplemented with probiotic.

The aim of this study was to evaluate the inclusion of different levels of probiotic in the diets of lambs, on ruminal characteristics, intake and digestibility of nutrients. The treatments were 0 (control group), 2, 4 and 6 g/day of probiotic doses, supplied orally and individually to the lambs. Four crossbred Santa Inês X Texel lambs were used, and the experimental design was a Latin square, with four treatments and four periods. Samples of diet, orts, feces, and ruminal fluid were collected from each animal. Intake and apparent digestibility variables were not different (p > 0.05) among the levels of probiotic evaluated. The average daily feed intake of lambs ranged from 1.27 to 1.28 kg of DM/day, and no significant differences (p > 0.05) were obtained between the levels of probiotics used in the diet. The percentage distribution of protozoa was not significant according to the different doses of probiotics used. A positive linear effect was obtained between the pH of the rumen fluid and the probiotic used, indicating that the highest pH values were obtained when the animals received the higher dose of 6 g probiotic; indicative that its use provides a ruminal environment closer to neutrality. The methylene blue reduction test in ruminal fluid samples did not differ between the different doses of probiotics used. The increasing levels of the probiotic in the diet of lambs are related to an increase in ruminal pH, without changing the levels of intake and digestibility of nutrients.

Heat stress on breeding value prediction for milk yield and composition of a Brazilian Holstein cattle population.

Due to the high milk production of Holstein cows, many countries have chosen to import semen to improve local dairy herds. This strategy would be more effective if this semen was used in the same environment conditions in which the bulls were selected. If the effect of genotype by environment (G × E) interaction is not considered, the estimated breeding values (EBVs) may vary, potentially reducing the selection response. We evaluate the impact of heat stress on selection for milk yield and composition of Holstein cows using random regression models. To verify the interference of heat stress in milk yield (MY) and composition traits (fat, protein, total saturated, and total unsaturated fatty acids content in milk), temperature-humidity index (THI) on test-day milk records was used. The threshold value to divide the environments using test-day information from Brazilian Holstein cows was 72 units of THI, i.e., < 72 represented no heat stress and > 72 represented heat stress. Legendre polynomials of second-order (Leg 2) model and two lactation points (33 and 122 DIM) were used to estimate heritabilities and EBVs for five important dairy traits. The heritabilities of milk components and fatty acids were low (0.09-0.29), regardless of lactation period and degree of heat stress, with the exception of protein content (0.30-0.35). Fat content was the only milk component that was reduced according to the degree of heat stress and lactation period. The EBVs tended to decrease in heat stress conditions, thus animals with high genetic potential demonstrated evidence of G × E interaction. However, acclimatization of dairy cows to heat stress in the farm production systems may have been responsible for the low differences among genetic parameters and EBVs with and without heat stress found in this study.

The COVID-19 pandemic's impact on the practices and biosecurity measures of veterinary medicine professionals in Brazil.

Veterinarians, among other health professionals, are considered health professionals at high risk of exposure to and contraction of COVID-19. The main objective of this study is to assess changes in the clinical practices of veterinarians during the COVID-19 pandemic around prophylactic and biosafety measures, as well as to evaluate changes in workload and cost-benefit ratio. An online questionnaire was sent to veterinary professionals from July 2020 to July 2021 using Google Forms. A total of 1134 veterinarians answered the questionnaire on clinical experiences and biosafety practices during the COVID-19 pandemic. Veterinarians changed their routine clinical practices, as there was a reduction in working hours, and applied new patient approaches and advice to their owners, as well as restricting the number of people allowed inside. Biosafety measures were added in their workplaces, with an increase in the use of personal protective equipment. COVID-19 tests were administered at least once in 19.0%, and more than once in 9.5% of the respondents. Flu symptoms were present in 23.8% of the respondents, and 31.0% of the veterinarians attended to COVID-19 positive pet owners. Therefore, most veterinarians altered their routine practices, and some were exposed to sources of COVID-19 infection.

Os médicos veterinários, entre outros profissionais de saúde, são considerados profissionais de saúde sob alto risco de exposição e contração do COVID-19. O objetivo principal do presente estudo foi avaliar as mudanças na prática clínica de médicos veterinários durante a pandemia de COVID-19 em torno das medidas profiláticas e de biossegurança, assim como avaliar as mudanças na carga de trabalho e a relação custo-benefício. De julho a dezembro de 2020, um questionário online foi enviado aos profissionais por meio da ferramenta Formulários Google. Um total de 1.134 veterinários responderam ao questionário relacionado às experiências clínicas e práticas de biossegurança durante a pandemia COVID-19. Os médicos veterinários mudaram suas práticas clínicas rotineiras, pois houve redução da jornada de trabalho, novas abordagens dos pacientes e orientações aos proprietários, além da restrição do número de pessoas nos locais. Medidas de biossegurança foram adicionadas aos locais de trabalho, com aumento do uso de equipamentos de proteção individual. Os testes COVID-19 foram realizados pelo menos uma vez em 19,0% e mais de uma vez em 9,5% dos entrevistados. Sintomas de gripe estavam presentes em 23,8% dos profissionais entrevistados e 31,0% dos veterinários atendiam tratadores de animais positivos para COVID-19. Portanto, a maioria dos veterinários alterou suas práticas de rotina e alguns foram expostos a fontes de infecção COVID-19.

Viability of the use of mycotoxin adsorbent in the finishing of Texel lambs in confinement.

The objective of the present study was to evaluate the viability of a mycotoxin adsorbent based on beta-glucans from cell walls of Saccharomyces cerevisiae and bentonites in the diets of confined lambs of the Texel breed. Twenty-four lambs (12 males and 12 females) with an average weight of 18.6 kg ± 1.6 were divided into two groups: treated (with adsorbent) and control. The animal diets contained the mycotoxins aflatoxin B1, fumonisin B1 and B2, zearalenone, and deoxynivalenol in concentrations within guidance levels. The animals were slaughtered with body weight of approximately 26.4 kg. The performance and carcass variables of the lambs were evaluated. The daily weight gain was higher in the treated group (216.24 g) than in the control group (185.90 g). The averages for loin eye area, subcutaneous fat thickness, and marbling were 13.93 cm2, 2.66 mm, and 3.20 in the treated group and 12.16 cm2, 2.6 mm, and 3.25 in the control group, respectively. The true, hot, and cold carcass yield, and the carcass cooling losses did not differ between groups. The carcasses were similar in conformation and fat finishing degree, with averages of 3.95 and 3.83, respectively. To the best of our knowledge, this is the first study to evaluate the effect of a mycotoxin additive in the diet of finishing lambs. The use of mycotoxin adsorbent in confined lambs was feasible, and its use resulted in greater daily weight gain in lambs and average net profit.

Relationship among productive and economic variables of beef cattle in Brazil / Relações entre variáveis produtivas e econômicas de bovinocultura de corte no Brasil

ABSTRACT: The present study aimed to obtain, through statistical methods, the independent variables that influence the economic and productive results of Brazilian beef cattle. Economic and productive information was collected from 106 farms in Brazil. Data collection was performed by the Instituto de Métricas Agropecuárias (Inttegra). The variable selection method used was stepwise regression followed by polynomial regression analyses. The variable beef cattle economic result showed the positive effect of disbursement per head per month and average weight gain. An average daily gain of 520 g in live weight was obtained, and this variable was influenced especially by nutrition cost. The arroba production (arroba is a unit of weight corresponding to 15kg) was influenced by the linear effect of nutrition cost and stocking rate. The variable arroba production in pasture showed a linear and positive effect of average weight gain in pasture and stocking rate in pasture. For profit per arroba, the variables nutrition cost, disbursement with pasture, and average sale price had a linear effect. The independent variables that had the greatest influence on the response variables were stocking rate, average daily weight gain, and nutrition cost. Thus, increases in investment in nutrition and stocking rate should result in higher production rates and improvements in the profitability of this activity.

RESUMO: O presente trabalho teve como objetivo obter, por meio de métodos estatísticos, quais variáveis independentes influenciam as variáveis econômicas e produtivas na bovinocultura de corte brasileira. O banco de dados utilizado foi obtido por coleta de informações econômicas e produtivas em 106 fazendas no Brasil. O método de coleta de dados foi definido pelo Instituto de Métricas Agropecuárias (Inttegra). Foram realizadas análises de seleção de variáveis pelo método Stepwise, seguido por análises de regressão múltipla. A variável resultado econômico da bovinocultura de corte teve efeito positivo do desembolso mensal por cabeça e do ganho de peso médio diário. Para o ganho de peso médio diário foi obtido um valor médio de 520 gramas, e esta variável foi influenciada principalmente pelo custeio com nutrição. Para a produção de arroba foi obtido efeito linear do custeio com nutrição e da taxa de lotação. Para a variável produção de arroba a pasto foi obtido um efeito linear e positivo do ganho médio diário de peso no pasto e da taxa de lotação no pasto. Para o lucro por arroba, as variáveis custeio com nutrição, desembolso com pastagem e preço médio de venda tiveram efeito linear. As variáveis independentes que tiveram maior influência nas variáveis resposta foram a taxa de lotação, o ganho médio diário de peso e o custeio com nutrição. Assim, aumentos no investimento em nutrição e na taxa de lotação dos animais devem resultar em maiores índices de produção e em melhorias na rentabilidade da atividade.

Nutrient intake and apparent digestibility coefficient of lambs fed with coffee husk in replacement of oat hay / Ingestão e coeficiente de digestibilidade aparente de nutrientes em cordeiros alimentados com casca de café em substituição ao feno de aveia

ABSTRACT: This study aimed to evaluate the effects of replacing oat hay with coffee husk in the diet of lambs on the intake and apparent digestibility of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), non-fiber carbohydrate (NFC), neutral detergent fiber (NDF), and acid detergent fiber (ADF). The experimental design was 4×4 Latin square with four levels of replacement of oat hay with coffee husk (0, 7.5, 15, and 22.5%) with four individually housed Texel sheep. Intake and apparent digestibility coefficients were measured at four periods of 12 days. All orts and feces were collected, weighed, homogenized, and sampled. The use of coffee husk at up to 22.5% of the total DM in the diet of lambs improved the intake of nutrients. Except for NDF, no significant differences were observed for the apparent digestibility of other parameters (DM, OM, CP, EE, NFC, and the ADF). Coffee husk can be included at up to 22.5% of total dry matter in diets with 30% roughage and 70% concentrate, being a good alternative to reduce feed costs in lamb production.

RESUMO: Objetivou-se avaliar os efeitos da substituição do feno de aveia pela casca de café na dieta de cordeiros no consumo e na digestibilidade aparente de matéria seca (DM), matéria orgânica (OM), proteína bruta (CP), extrato etéreo (EE), carboidratos não fibrosos (NFC), detergente neutro fibra (NDF) e fibra em detergente ácido (ADF). O delineamento experimental utilizado foi quadrado latino 4×4, com quatro níveis de substituição do feno de aveia por casca de café (0; 7,5%; 15%; 22,5%) e quatro ovinos Texel, os quais foram alojados individualmente. O consumo e os coeficientes de digestibilidade aparente foram mensurados em quatro períodos de 12 dias. Todas as sobras e fezes foram coletadas, pesadas, homogeneizadas e amostradas. O uso de casca de café na dieta de cordeiros com até 22,5% de DM melhorou o consumo dos nutrientes. Não foram observadas diferenças significativas para a digestibilidade aparente da DM, OM, CP, EE, NFC e ADF, exceto para o NDF. A casca de café pode ser incluída em até 22,5% da matéria seca total de dietas com 30% de volumoso e 70% de concentrado, sendo uma boa alternativa para reduzir os custos de alimentação na produção de cordeiros.