The objective of this trial was to investigate intake, apparent total tract digestibility of nutrients, passage rate, average daily gain, carcass yield, and feed conversion in beef cattle fed diets containing four levels of CP (9, 11, 13 and 15%) and forage:concentrate ratio of 60:40. Twenty-four young Zebu bulls were assigned to a completely randomized block design with four treatments and six replications. The experiment lasted 84 days with 15 days for diet adaptation and three periods of 28 days […]

This experiment aimed to determine the effects of exogenous enzyme (porcine pancreatin) supplementation to microdiet on pacu Piaractus mesopotamicus growth, survival and changes on digestive tract morphology. Eight feeding programs were performed: Artemia nauplii feeding (AV), microdiet with enzymatic supplementation (DMP) or without supplementation (DM), weaning at the 5th day with supplemented (AV5DMP) or not supplemented diet (AV5DM) and weaning at the 10th day with supplemented diet (AV10DMP) or not supplemented diet (AV10DM). The experiment lasted 28 days. Larvae fed […]

The objective of this trial was to investigate the effects of diets containing corn silage, bermudagrass hay, or elephantgrass silage on intake and apparent total tract and partial digestibilities of nutrients in cattle. A forage to concentrate (soybean meal) ratio of 90:10 was used. Six ruminally and omasally fistulated bovines averaging 351 kg of initial body weight were used in two replicated 3 x 3 Latin squares. Each experimental period lasted 16 days with 10 days for animal adaptation and […]

The aim of this experiment was to determine the best level of salt for Japanese laying quails (Coturnix coturnix japonica). Three hundred and thirty-six quails with 13 weeks of age were housed in cages with 118 cm2/quail for 84 days (four cycles of 21 days each). The experiment was analyzed as a complete randomized design with seven treatments (0, 0.15, 0.20, 0.25, 0.30, 0.35, and 0.45% of salt) with six replicates of eight quails per pen. Every 21 days, the […]

This experiment was conducted to estimate DM digestibility, fecal output, and DM intake of sheep fed a diet containing oat hay and concentrate. Treatments consisted of two methods of administration of the external marker alkane (C32): equilibrium and pulse dose. In the equilibrium treatment, animals received one daily pellet of cellulose containing 100 mg of C32 during eight days (four days for reach steady state conditions and five days for sample collection). Animals in the pulse dose treatment received only […]

This research was conducted to compare the accuracy of two mathematical models to predict calcium (Ca) metabolism in sheep supplemented with different Ca sources. Twenty Brazilian male sheep averaging 7 to 8 months of age were fed a basal diet containing corn, soybean meal, hydrolyzed sugarcane bagasse, urea, mono-ammonium phosphate, mineral mixture and one of the following Ca sources: limestone (LM), alfalfa hay (AH), dicalcium phosphate (DP), oyster shell meal (SM), and citrus pulp (CP). On day 22 each animal […]

Two experiments were conducted to evaluate different crude protein (CP) levels of a mixture of mineral and concentrate (multiple supplement) fed to crossbreed steers grazing Panicum maximum cv. Mombaça pasture during the transition between the dry and the rainy season. The multiple supplement contained ground corn and soybean grains and was formulated to yield 8.0, 16.0 or 24.0% of CP. Each animal received 1.0 kg of the multiple supplement per day or only ad libitum mineral mix (control treatment). In […]

The experiment was conducted to evaluate the effect of different energy levels and feeding programs on performance of broilers from 42 to 57 days of age. One thousand and six hundred 1-d male chicks (Cobb) were assigned to a completely randomized design with 2 x 4 factorial arrangement (two levels of energy: 3,200 and 3,600 kcal ME/kg and four different feeding programs: amino acid recomendations). From 1 to 41 days of age all birds were fed the same corn and […]

The effects of total excreta collection period length on estimated values of metabolizable energy [apparent (AME) and nitrogen corrected (AMEn)] were evaluated in broiler chickens from 19 to 23 days of age. Five treatments with six replicates were used in a randomized block design, in a total of 300 broiler chicks for the control and 300 broiler chicks for the reference diet. The control replaced 40% of reference diet with corn. After diet adaptation (four days), total excreta collection was […]

A bio-economic model was developed to calculate costs and revenues to obtain economic values (EV) for performance traits of beef cattle in production systems in Brazil. Performance records, economic and biologic parameters were obtained from a Nelore breeding herd. Two production systems: complete breeding cycle (CbcR) and cow-calf (Cc) were simulated using a deterministic and static model. Costs, revenues and the annual profits were calculated using Excel® to obtain the economic values for weaning weight (WW), mature weight (MW), pregnancy […]