Abstract This study evaluated the inclusion of concentrate and monensin, salinomycin and flavomycin in sheep diets on intake, digestibility, in situ degradability, ruminal variables and nitrogen balance. Five sheep in a latin square received the treatments: HAY (hay only), CONT (hay + concentrate), MON (hay + concentrate + monensin), SALI (hay + concentrate + salinomycin), and FLAV (hay + concentrate + flavomycin). Hay was offered ad libitum, concentrate, 20 g kg-1 of body weight (BW), and additives, 0.75 mg kg-1 of BW. The treatments with the concentrate (CONT, MON, SALI and FLAV) showed increased (P≤0.05) on intake, digestibility, total VFA, propionate and butyrate proportions, N-NH3, and nitrogen balance, and decreased (P≤0.05) DM and NDF degradability, acetate proportion, acetate:propionate ratio, and rumen pH compared to the HAY. The comparison between the outcome effects from additives with the CONT showed that the acetate proportion and acetate:propionate ratio was only reduced by MON (P≤0.05). MON and SALI increased (P≤0.05) the propionate proportion. The proportion of butyrate was increased with the inclusion of FLAV and reduced with MON 8and SALI. Only MON reduced the production of N-NH3 (P≤0.05). Other variables showed no effects from additives (P>0.05) in relation to the CONT. The inclusion of the concentrate in sheep diets caused alterations on intake, digestibility, ruminal variables (VFA, pH, and N-NH3) and nitrogen balance. However, the additives only altered the ruminal variables (VFA and N-NH3) and the greatest effects were observed with MON.

Resumen El presente estudio evaluó la inclusión de concentrado con monensina, salinomicina y flavomicina en dietas para ovinos, evaluando consumo, digestibilidad, degradabilidad in situ, variables ruminales y balance de nitrógeno. Cinco ovejas, bajo un diseño de cuadrado latino, recibieron cada uno de los tratamientos: HENO (solo heno como tratamiento control), CONT (heno + concentrado), MON (heno + concentrado + monensina), SALI (heno + concentrado + salinomicina) y FLAV (heno + concentrado + flavomicina). HENO fue suministrado ad libitum, mientras que el concentrado fue a 20 g kg-1 de peso corporal (PC) y los aditivos a 0.5 mg kg-1 de PC. Los tratamientos con el concentrado (CONT, MON, SALI y FLAV) mostraron un aumento (P≤0.05) en consumo, digestibilidad, AGV totales, proporciones de propionato y butirato, N-NH3 y balance de nitrógeno, y disminuyeron (P≤0.05) degradabilidad de materia seca y fibra en detergente neutro, proporción de acetato, relación acetato: propionato y pH del rumen comparado con el tratamiento control. La comparación entre los efectos dados por los aditivos con el CONT mostraron que la proporción de acetato y la relación acetato:propionato solo se redujeron en MON (P≤0.05). MON y SALI aumentaron (P≤0.05) el propionato, mientras que el butirato incrementó con la inclusión de FLAV, reduciéndose con MON y SALI. Únicamente MON disminuyó la producción de N-NH3 (P≤0.05). Otras variables no mostraron efectos de los aditivos (P>0.05) en relación con CONT. La inclusión del concentrado en las dietas para ovejas causó alteraciones en el consumo, digestibilidad, variables ruminales (AGV, pH y N-NH3) y balance de nitrógeno, sin embargo, los aditivos solo alteraron las variables ruminales (AGV y N-NH3), observando los mayores efectos con el MON.

ABSTRACT The objective of this study was to evaluate the effects of injectable trace minerals (ITM) on growth, health, antioxidant enzyme activity, and immune system of newborn Boer kids. Newborn kids (n = 125) were assigned to one of two treatments: injection (0.1 mL 4.5 kg-1) of saline or ITM. Injectable trace minerals had 60, 10, 5, and 15 mg mL-1 of Zn, Mn, Se, and Cu, respectively. Kids were evaluated daily for the presence of diarrhea and weighted on d 0, 28, and 56. Blood samples were obtained on d 0, 3, 7, 14, 28, and 56. The ITM injection increased the plasma concentration of superoxide dismutase (d 14), glutathione peroxidase (d 3 and 7), and blood platelets (d 7) compared with saline injection. Kids receiving ITM showed greater amount of blood eosinophils and less mean corpuscular hemoglobin (MCH; d 3) and mean corpuscular hemoglobin concentration (MCHC) compared with kids receiving saline injection. The ITM injection did not affect other components of leukogram and erytogram. The ITM-injected kids tended to have less diarrhea incidence compared with saline-injected kids (20.7 vs. 34.8±7.10% respectively). The ITM injection did not affect mortality rate and growth. Therefore, a single ITM injection administered to newborn Boer kids increases the plasma concentration of antioxidant enzymes, platelets, and eosinophils, reduces MCH, MCHC, and tends to reduce the incidence of diarrhea, but does not affect mortality and growth.

Objetivou-se avaliar o efeito de níveis crescentes de concentrado sobre a produção dos componentes carcaça e não-carcaça de borregas confinadas. Vinte e quatro borregas mestiças foram aleatoriamente distribuídas em quatro tratamentos: dieta com 20%; 40%; 60%; 80% de concentrado. Os animais foram abatidos quando aqueles que recebiam a dieta 80% de concentrado atingiram o peso adulto (50 kg PV). Os dados foram analisados por meio de análise de variância e regressão. Os pesos da paleta e da perna cresceram linearmente com o aumento dos níveis de concentrado, porém, o rendimento da paleta não foi influenciado com média de 16%, e o rendimento da perna reduziu linearmente (28g para cada 1% de concentrado adicionado). O valor percentual das vísceras reduziu linearmente, assim como da cabeça e patas. Os componentes não-carcaça representaram valores de 34,64; 38,60; 38,55 e 39,88% do PV para os níveis de 20, 40, 60 e 80% de concentrado, respectivamente. Conclui-se que os pesos dos cortes são influenciados positivamente pelo aumento dos níveis de concentrado. O aumento dos níveis de concentrado proporciona menor percentual de vísceras e aumento na deposição de gordura subcutânea dos cortes cárneos comerciais.

The objective of this study was to evaluate the effect of increasing levels of concentrate on the production of carcass and non-carcass components of feedlot ewes. Twenty-four crossbred ewes were randomly distributed in four treatments: diet with 20%; 40%; 60%; and 80% concentrate. Animals were slaughtered when those receiving the diet with 80% concentrate reached adult live weight (50 kg LW). The data were analyzed by variance and regression analyses. The weights of the shoulder and leg rise linearly with the increase in the levels of concentrate, but shoulder yield was not affected, with an average of 16%, and the leg yield reduced linearly (28 g for each 1% concentrate added). The percentage value of the viscera reduced linearly, as well as those of head and paws. The non-carcass components represented values of 34.64; 38.60; 38.55; and 39.88% of the LW for the levels of 20, 40, 60 and 80% of concentrate, respectively. The weight of the cuts is affected positively by the increase in the levels of concentrate. The increase in the levels of concentrate promotes lower percentage of viscera and increase in the deposition of back fat of the commercial meat cuts.