This research was carried out to evaluate the use of pre-starter diets, through different periods to broilers with different first day weights. Two hundred and eighty one-day old chicks were allotted in brooded battery cages, in a completely randomized design, with six treatments and four replicates in a factorial design 2 x 3, (chicks weight – higher or lower than 40 g, and pre-starter periods of feeding, 1 to 7; 1 to 10 and 1 to 14 days). The performance […]

An experiment was carried out to estimate the relations between broiler carcass weight and thighs+drumsticks, breast+bone+skin, and breast meat by the linear model. Eight hundred and sixty and four male poultry of Arbor Acres strain, from 22 to 42 days of age, were assigned to a completely randomized design in 3x4factorial scheme. Corn and soybean meal based diets were prepared to contain 2900 kcal ME and 15.43; 17.26; 19.60; and 22.60% CP; 3,100 kcal ME and 16.49; 18.45; 20.95; and […]

Sixty barrows from crossing between commercial hybrids with an average initial weight of 95.7 ± 0.80 kg and an average final weight of 109.8 ± 1.13 kg were used to evaluate different dietary lysine levels on performance and on carcass characteristics. The experimental design used was a randomized blocks with five treatments, six replicates and two animals per replicate. The treatments corresponded to a basal diet with 13.7% of crude protein, 3367 kcal DE/kg supplemented with five L-lysine-HCl levels, resulting […]

An experiment in the biotherium of Nutrition Department/UFV aiming to evaluate the effects of rotten corn and the quality of your protein for growing rats. Thirty Wistar female rats early weaned, with 22 days of age and average initial weight of 53.9 ± 3.2 g were assigned to a randomized design. With five treatments and six repetitions with one animal by experiment unity. The treatments consisted in a basal ration (positive control), like a casein standard, four rations with corn […]

Records on 6,674 Nellore cattle weight, born from 1975 to 1990 in two farms located in Paraiba State were used to study environmental effects and to estimate genetic parameters for average daily gains from birth to 205 days, from 205 to 365 days and from 365 to 550 days. The SAS® program was used to study the environmental effects. The model included the random effect of sire and the fixed effects of year-month-sex, farm and age of the cow at […]

The objective was to evaluate the effect of temporary mother-litter separation on the reproductive performance of lactating does and growth performance of their litters up to 70 days of age. A total of 415 presentations of 157 lactating does assigned to two groups: control, with free nest access, and treated, whose nest access was closed during the 39 hours that preceded mating, were analyzed. From the 415 presentations, 387 resulted in matings and 264 in parturitions. Does of the treated […]

The economic values of dairy cattle were derived from economics and production data of a demonstration farm, the “Pasture Dairy Production System using Holstein Zebu Cattle” at Embrapa-Dairy Cattle. The economic values were estimated by two methods 1) from the partial derivative of profit with respect to each trait, and 2) from the partial derivative of the income/cost ratio, both evaluated at the mean value of all other traits. With the latter method, the economic values of traits considered, expressed […]

153,963 test day milk yield records and 13,273 first lactations of Holstein cows calving between 1989 and 1998, were used with the objective of estimating genetic, phenotypic and environmental parameters for test day milk yield (PLDC) and 305 day milk yield (P305) and to study the convenience of using test day yields in genetic evaluations to replace P305. Four models were used. Models 1 and 2 differed according contemporary grouping and monthly milk records were considered as repeated measures. In […]

Genetic parameters for first lactation test-day milk yields and 305 day milk yield (M305) for Caracu cows were estimated. The test-day animal model included additive genetic effect as random and contemporary group and age of cow (quadratic regression) as fixed effects. Two contemporary groups were defined to explain variation, composed by year, week of test and paddock (gc1) or year, week of test and paddock (gc2). Variance components were estimated by Restricted Maximum Likelihood. Phenotypic, residual and genetic additive variances […]

The follicular dynamics and luteal regression were studied in 12 Gir and seven Nelore cows, treated with prostaglandin F2a analog, between days 10 and 12 of the estrous cycle. The synchronization rate was higher than 92% for the Gir and Nelore cows, and the ovulation of the second dominant follicle occurred in 72.7% of the Gir and all the Nelore cows. The Nelore ovulatory follicle diameter was lower than Gir cows ((11.0 ± 0.9 mm x 13.0 ± 1.7 mm). […]