Stochastic simulation was carried out to access the consequences of combined use of assortative mating and sexed semen in a beef cattle population under selection. Six generations of selection were simulated under three different scenarios of mating strategy and sexed semen use. The first was characterized by random mating and no use of sexed semen. The second was simulated using positive assortative mating (PAM) for the 40% top dams and negative assortative mating (NAM) for the remainder, with no use […]

Supplementation of 5 ppm of ractopamine, associated or not to feed restriction in diets with a high total lysine content (1.04%) was evaluated on performance and nitrogen balance. In experiment 1, 60 hybrid castrated male swine (76.2 ± 2.3 kg) were housed in pairs according to a randomized complete block design in a factorial treatment arrangement (2 ×2 + 1) with or without ractopamine supplementation, two forms of feeding, ad libitum and feed restriction with 1.04% lysine, and an additional […]

The objective of the study was to determine whether bioavailability of methionine hydroxy analogue free acid (MHA-FA) is higher than 65%, in product basis, for 24 to 40 week-old laying hens. Six hundred and forty 24-week commercial laying hens were used in four 28-day experimental periods in a randomized complete design with ten treatments, eight replications and eight birds per experimental unit. The treatments were based on a basal feed deficient in methionine, containing 2,830 kcal metabolizable energy (EM)/kg and […]

This experiment was carried with Japanese quails in the egg production phase with the objective of determining the requirements of digestible methionine + cystine (M+C) for higher production and egg quality. A total of 240 Japanese quails were distributed in a randomized complete block design. The basal diet was supplemented with different DL-methionine levels, corresponding to digestible methionine + cystine levels of 0.55, 0.61, 0.67, 0.73 and 0.79%. The characteristics analyzed were feed intake (g/quail/day), egg production (%), egg weight […]

The objective of this study was to evaluate the effect of adding antibiotics, probiotics, prebiotics, symbiotic and sodium gluconate for swine from 28 to 142 days of age, corresponding to the nursery, growing and finishing phases. One hundred and sixty-eight piglets were used weaned at 21 days in a randomized complete design in 42 pens with four male piglets in each experimental unit with six replications and seven treatments: control basal feed; basal feed + antibiotic; basal feed + probiotic; […]

The objective of this study was to evaluate the effect of including guava wastes in the feed on the performance and carcass yield of broiler chickens. An experiment was carried out with 300 male Cobb strain chicks, in a randomized complete design with five levels of waste and five replications. A reference diet based on corn and soybean meal and four feeds with 3, 6, 9 or 12% guava waste were evaluated. The feed intake, weight gain and feed conversion […]

Three experiments were carried out to evaluate the effect of adding enzymatic complex (EC) on the nutritive value of soybean hulls (SH) in starting pig feeding. The enzyme complex used contained α-galactosidase, β-glucanase, galactomananase and xilanase. In experiment 1, the digestibility of soy bean hull with addition of enzyme complex was determined at three levels (0, 200 and 300 mg/kg), using piglets with initial body weight of 22.49 ± 1.73 kg. None of the enzyme complex levels affected the soy […]

Three trials with were conducted to evaluate the effects of diets with 53% rye (diet C) or 53% wheat (diet T) supplemented or not with xylanase enzymes (0.06%) on nutrient digestibility and metabolizable energy and the performance and development of the broiler chicken digestive tract. A diet with 53% corn was used as control. In trial 1, dry matter, organic matter and apparent fat digestibilities corrected for nitrogen (EMAn) were lower in rye diets than in wheat diets (2556 kcal/kg […]

The objective of this study was to reevaluate the requirements of Methionine+cystine (met+cis total) of light (L) and semi-heavy (SH) pullets at 5 to 11 weeks of age considering the physical shape of the feeds and the performance in the 22 to 40 week period, the laying phase. A total of 1,120 laying pullets (560 lightweight and 560 semiheavy) in a randomized completedesign in a 5 ×2 ×2 factorial scheme with 20 combinations consisting of five total Met+Cys levels (0.56; […]

In this experiment, sorghum substitution with full-fat corn germ meal was evaluated in feed for broiler chickens. Two experiments were carried out in a randomized complete design with four levels of substitution of sorghum substitution with full-fat corn germ meal (0, 33.3, 66.7 and 100%) as energetic concentrate in diets produced exclusively with vegetable ingredients (experiment 1) or with ingredients of animal origin (experiment 2) with four replications each. Performance (weight gain, feed intake and feed conversion) were evaluated and […]