ABSTRACT The objective was to evaluate the addition of antibiotic growth promoters to free-choice mineral supplement on ingestive behavior, mineral intake, and growth performance of grazing bulls. Sixty Nellore bulls [initial body weight (BW) of 219±17.8 kg and 15±2 months of age] were divided in 12 marandu grass paddocks. The treatments were: mineral supplement (control), mineral supplement + virginiamycin (VIRG), mineral supplement + lasalocid sodium (LASA) and mineral supplement + salinomycin sodium (SALI). Mineral supplements were formulated with target intake […]

ABSTRACT An evaluation of the effects of monensin and calcium propionate on the in vitro kinetics of gas production, digestibility, carbon dioxide, and minor gas production on different days was performed using the ruminal fluid from eight Suffolk lamb donors, after receiving additives for 1, 10, and 20 days. Treatments consisted of a control ration of 40% grain; 30 mg/kg of monensin in a diet with 40% grain; 10 g/kg calcium propionate in a diet with 30% grain; and the […]

The objective of this trial was to compare the effect of compensatory growth regime on the metabolic profile and mammary gland development of dairy heifers. Twenty Brown-Swiss heifers averaging 200 kg of body weight and five months of age were used in a completely randomized design with a 2 × 2 factorial arrangement. The treatments were arranged in a factorial arrangement (2 × 2) and the animals were randomly allocated in each one of the combinations. The factor 1 consisted […]

The objective of this paper is to assess the effects of the inclusion of different levels of green propolis extract in the diet of lambs in feedlot on ingestive behavior, nutrients digestibility, physiological parameters and performance. Eight lambs were distributed in double Latin Square with four treatments, corresponding to the inclusion levels (4, 8, 12, 16 mL) of green propolis ethanolic extract (30 g of ground crude propolis was infused in a 100-mL hydroalcoholic solution, 700 mL/L). The diets were […]

The objective of this study was to evaluate the influence of the ionophore monensin on the intake, weight gain, feed:gain ratio and withers and croup heights of heifers maintained in feedlot, and also the feeding costs. Twenty eight Holstein heifers were confined individually for 84 days, and fed diets containing 32.84% concentrate (corn grain, soybean meal, urea and mineral mix) and 67.16% corn silage and sugar cane, at the proportion of 1:1 in DM. The ionophore levels added to the […]

Four lactating dairy cows with ruminal cannula and 155 DIM were allotted to a 4 × 4 Latin square and fed twice daily corn silage and concentrate (55:45, %DM) to evaluate the effect of monensin and soybean oil in the diet of lactating cows on the counting of ciliate protozoa beyond establishing correlations between number of protozoa with some parameters of digestion and ruminal fermentation. The treatments consisted of the inclusion of 33 ppm of sodium monensin or soybean oil […]

The objective of this trial was to evaluate the effect of monensin in the apparent digestibility of nutrients in diets with different levels of CP. Twenty-five castrated rams were housed in metabolism cages for 20 days and fed diets with 11.4 or 16.5% of CP (% DM) supplemented or not with 28 mg of monensin/kg of DM. Diets contained 65% of signalgrass hay (Brachiaria decumbens) and 35% of concentrate; a diet containing only signal grass hay was also fed. The […]

The objective of this trial was to evaluate the effects of dietary monensin and soybean oil on milk fatty acid (FA) profile in the 5th and 15th week of lactation of dairy cows. Sixteen multiparous crossbred dairy cows averaging 30 days in milk were assigned to a completely randomized block design in a 2 x 2 factorial arrangement (presence or absence of monensin and soybean oil). The following diets were used: control not supplemented with monensin or soybean oil (CT), […]

The objective of this trial was to study the effects of different dietary levels of the ionophore monensin on apparent digestibility of nutrients and on ruminal, blood, and urinary metabolites in dairy heifers. Samples of ruminal fluid (pre-feeding and 2 hours post-feeding), blood, urine, and feces all were collected from 28 confined Holstein heifers. Diets contained (dry matter basis): 32.84% of concentrate (corn grain, soybean meal, urea, and mineral salt mixture), 33.58% of corn silage, and 33.58% of sugarcane. The […]

Four ruminally fistulated Holstein steers were fed four times a day (8 a.m., 11 a.m., 2 p.m. and 5 p.m.) with four diets with low and high protein content, with or without monensin, to verify the effect of monensin on feed intake and ruminal fermentation. Diets contained (dry matter basis): low (11.4 %) and high (16.5%) crude protein content, 65% of brachiaria hay (Brachiaria decumbens) and 35% of concentrate. Corn and urea- and corn and soybean meal- based diets were, […]