The effect of Haemonchus contortus and Trichostrongylus colubriforms infection on the ruminal microbiome of lambs.

We evaluated Haemonchus contortus (HC) and Trichostrongylus colubriformis (TC) infection on the ruminal microbial community of Santa Ines lambs to better understand the pathophysiology of parasite infections and the interactions among gastrointestinal nematodes and gut resident microbiota. In this study, 18 six months of age lambs were maintained for 34 days in individual pens divided into three treatments that included animals infected with HC and TC, and control (infection-free). Haematological, ruminal parameter and microbial nitrogen absorbed by pune derivatives, as well as enteric methane emission (CH4), were analysed, and the rumen microbial taxonomic and functional profile assessed by shotgun metagenomics. The analysis showed that total protein, albumin, urea, and butyrate level were lower in animals infected by both parasites, while HC infection also decreased the haemoglobin level. Both infected groups (TC and HC) increased the enteric methane emission (CH4). TC and HC infections increased the diversity and richness of functional microbial genes. Most alterations in the rumen microbiome composition of infected groups are associated with the suppression of microbes involved in microbial homeostasis maintenance and expansion of the archaeal community in the infected animals. Infection led to an increased abundance of nitrogen, amino acid, protein, and energy metabolism genes. Overall, TC and HC infection increased the enteric methane emission, negatively affected taxon's responsible for maintenance de rumen homeostasis and modulated some important genes related to protein and energy metabolism.

Growth performance, carcass traits and meat quality of lambs fed increasing level of Macadamia nut cake.

A total of 40 lambs were divided into four different treatments according to the inclusion level of the macadamia nut cake: C-control (0%), M1 (6.5%), M2 (12%) and M3 (20%). Feed was provided twice a day; animal weighing along with body condition scoring occurred within a 14-day interval. The lambs were slaughtered at the end of the performance test. Analysis of variance was performed through the Mixed procedure of the SAS, as well as linear and quadratic regression analysis. The groups presented differences between the treatments (P <0.05) for dry matter intake (DMI), ethereal extract intake (EEI), consumption in relation to live weight percentage and feed conversion ratio (FCR). The lowest mean DMI was obtained by the animals that received the M2 and differed from the C treatment, whose average was the highest. The EEI was highest for the M3 group and the FCR was also better for this group. There was a linear effect for EEI and FCR, and quadratic for crude protein intake. There was no effect for carcass characteristics, and only initial pH had a decreasing linear effect. The macadamia nut cake was effective in promoting the performance of the animals, since there was an improvement in feed conversion.

Effect of castration and vitamin E supplementation on carcass and meat quality of Santa Inês lambs / Efecto de la castración y de la suplementación con vitamina E sobre la canal y la calidad de la carne de corderos Santa Inês / Efeito da Castração e da suplementação de vitamina E sobre a carcaça e qualidade da carne de ovinos Santa Inês

Abstract Background: Carcass and sheep meat quality are influenced by several factors, such as race, age, slaughter weight, type of diet, and dietary supplementation. Objective: To evaluate the effect of castration and vitamin E supplementation on performance, carcass characteristics and meat of lambs slaughtered at 45 kg. Methods: Thirty-two male lambs (16 castrated and 16 not castrated) were fed diets with or without the inclusion of vitamin E. The animals had an average age of 180 ± 20 days and a mean weight of 25.1 ± 4.6 kg. Performance was evaluated for 56 days, and the animals were slaughtered when reaching a weight of 45 kg. The experimental design was randomized blocks based on initial weights, and variables were assessed by a 2x2 factorial design (castrated and intact, supplemented or not with vitamin E, with a probability of 5%). Results: Higher proportion (p<0.05) of visceral fat was found in castrated animals (kidney: 2.45%, inguinal: 0.57% and omental: 4.96%) than in intact animals (kidney: 1.25%, inguinal 0.27%. and omental 3.12%). The aged meat samples showed no color differences for any of the treatments, but there were differences in shear force for steaks aged for 7 days, where the castrated animals showed an average of 2.64 kgf and intact animals showed an average 3.29 kgf. The animals supplemented with vitamin E had lower shear forces in non-aged samples. Conclusion: Castration increased deposition of visceral and fat coverage but did not influence the cut yields and total carcass yield. The animals supplemented with vitamin E had lower shear forces in non-aged samples.

Resumen Antecedentes: La calidad de la canal y de la carne de ovino puede ser influenciada por varios factores, como raza, edad, peso de sacrificio, tipo de dieta y suplementación. Objetivo: Evaluar el efecto de la castración y de la suplementación con vitamina E sobre el desempeño, la calidad de la canal y la carne de corderos Santa Inés sacrificados a los 45 kg de peso. Métodos: Fueron utilizados treinta y dos corderos: dieciséis castrados y dieciséis no castrados, alimentados con dietas con o sin inclusión de vitamina E. Los animales tenían una edad promedio de 180 ± 20 días y un peso promedio de 25,1 ± 4,6 kg. Fue evaluado el desempeño durante 56 días y, al llegar a los 45 kg de peso fueron sacrificados. El diseño experimental fue en bloques aleatorizados con base en el peso inicial, y las variables analizadas mediante un modelo factorial 2x2 (castrado o no castrado y suplementado o no con vitamina E, con una probabilidad del 5%). Resultado: Se encontró mayor proporción (p<0,05) de grasa visceral en los animales castrados (renal: 2,45%; inguinal: 0,57% y mesentérica: 4,96%) que en los no castrados (renal: 1,25%; inguinal 0,27% y mesentérica: 3,12%). Las muestras de carne maduradas no presentaron diferencias de color entre tratamientos, sin embargo hubo diferencias en la fuerza de corte para las carnes maduradas por 7 días, donde los animales castrados presentaron una media de 2,64 kgf y los no castrados de 3,29 kgf. La carne de los animales suplementados con vitamina E tuvo menor fuerza de corte en las muestras no maduradas. Conclusión: La castración aumentó la deposición de grasa visceral y de cobertura pero no influenció las características de rendimiento total de la canal y cortes. Los animales suplementados con vitamina E tuvieron menor fuerza de corte en las muestras no maduradas.

Resumo Antecedentes: A qualidade da carcaça e da carne ovina pode ser influenciada por vários fatores como raça, idade, peso de abate tipo de dieta e suplementação. Objetivo: Avaliar o efeito da castração e da suplementação de vitamina E sobre o desempenho e qualidade de carcaça e carne de cordeiros Santa Inês abatidos a 45 kg de peso. Métodos: Foram utilizados trinta e dois cordeiros, dezesseis castrados e dezesseis não castrados alimentados com dietas com ou sem inclusão de vitamina E. Os animais tinham idade média de 180 ± 20 dias e peso médio de 25,1 ± 4,6 kg. Foi avaliado o desempenho durante 56 dias, e ao chegarem aos 45 kg foi realizado o abate. O delineamento experimental foi em blocos ao acaso, com base no peso inicial, e as variáveis analisadas por modelo fatorial 2x2 (castrado ou não castrado e suplementado ou não com vitamina E, ao nível de 5%). Resultado: Foi encontrada maior proporção (p<0,05) das gorduras viscerais nos animais castrados (renal: 2,45%; inguinal: 0,57% e omental: 4,96%) do que nos animais não castrados (renal: 1,25%; inguinal 0,27% e omental: 3,12%). As amostras maturadas não apresentaram diferenças de cor entre os tratamentos, no entanto houve diferenças na força de cisalhamento para as carnes maturadas por 7 dias, na qual os animais castrados apresentaram média de 2,64 kgf e os não castrados de 3,29 kgf. Os animais suplementados com vitamina E apresentaram menores forças de cisalhamento nas amostras não maturadas. Conclusão: A castração aumentou a deposição de gorduras viscerais e de cobertura, mas não influenciou as características de rendimento de carcaça e cortes. Os animais suplementados com vitamina E tiveram menor força de cisalhamento nas amostras não maturadas.