This study was carried out to determine the best digestible energy and digestible protein ratio in feeds for Nile tilapia (Oreochromis niloticus) juveniles 30.0 ± 4.21 g) based on digestible amino acids and the ideal protein concept). Twelve rations were formulated with protein levels 22.0; 26.0; 30.0 and 34.0% of digestible protein and levels 3,000, 3,300 and 3,600 kcal/kg digestible energy. The digestible energy/digestible protein ratio was between 8.94 and 15.19 kcal/g. Three hundred and twenty four tilapias were randomly […]

This study was carried out to determine the best digestible protein/digestible lysine ratio that should be present in feed fed to Nile tilapias. Two hundred and sixteen tilapias (11.0 ± 0.43g) were distributed in 36 fish tanks (205 L) at a density of 6 fish/tank. Twelve feeds were formulated with three different digestible protein (DP) levels 22.0; 26.0 and 30.0% (based on digestible amino acids) and four different lysine percentages of 4.5; 6.0; 7.5 or 9.0% in relation to digestible […]

The relationship between the quality of dietary crude protein and health of bullfrog juveniles (Lithobates catesbeianus) was evaluated by necropsy and histopathological examination of animals. The histopathology results showed that animals fed different feeds, regardless of CP levels, presented lymphocytary hepatitis, colitis and flattened microvillosities; kidneys with areas of tubulonephrosis and renal tubule calcification; myocarditis and cardiac muscular fiber dissociation. Such injuries suggested a degenerative nutritional process, with development of inflammatory processes spread to all the organs. These findings suggested […]

A field experiment was carried out to evaluate the morphogenetic characteristics of pearl millet (Pennisetum glaucum (L.) R.Br.), under rotational grazing with the following rest periods between grazings (RP), corresponding to the time required for expansion from: RP 1.5 to 2 leaves, RP 2.5 to 3 leaves and 3.5 to 4 leaves. Morphogenic characteristics were evaluated in four replications of the area (paddocks) and consisted of leaf blade growth, leaf senescence, stem growth, leaf appearance, phillochron and leaf life-span. The […]

Records of 19,458 Nellore breed animals, born from 1975 to 2002, from 8 herds participating in the Nellore Cattle Breeding Program (NCBP) were used to estimate (co)variance components, heritability and genetic correlations for birth weight, weaning weight, weight after yearling and at 2, 3 and 5 years of age. The restricted maximum likelihood method, with univariate, bivariate and multivariate analyses, was used. The models included the random additive genetic direct effect (animal) and fixed effects of age group and the […]

In order to provide knowledge for breeding, conservation programs and expansion policies of the Indubrasil breed from northeastern Brazil, the evolutionary history, estimates of genetic parameters and the populational structure of the breed were studied. Pedigree information was used from animals born from 1964 to 2006 and the adjusted weights at 205, 365 and 550 days of age of bovines born from 1976 onwards. The heritability coefficient estimates were lower than those reported in the literature for the adjusted weights […]

The objectives of this study were to verify whether propolis and ascorbic acid have an effect on plasmatic membrane integrity of goat spermatozoa and investigate the potential of these antioxidants in the use of goats spermatozoa cryopreservation extenders. Five adult boars were used of the Alpine (n = 2) and Saanen (n = 3) breeds. After semen collection, the evaluation consisted of the physical and morphological exam, live and dead cells (supravital test) and hyposmotic swelling test. Afterwards, the fresh […]

The objective of this study was to analyze the relationships between previously estimated individual growth curve parameters (mature weight and maturing rate) and measures of productive efficiency of 333 Holstein-Friesian cows, born from 1992 to 2002. Data on age at first calving, first lactation milk yield, first lactation length, first calving interval and milk yield per day of first calving interval were analyzed using a generalized linear model with the fixed effect for age group (year-season of birth), the random […]

The objective of this study was to evaluate impacts of ignoring the dominance effects on the estimation of genetic parameters and prediction of genetic values by the restricted maximum likelihood method, under the additive animal model, using MTDFREML. Two gene action models were simulated for the same genomic architecture: one model that included only additive effects of the genes and the other with additive effects and positive and complete dominance into 100% of the loci. Under each genetic model, three […]

The objectives of this study were to evaluate the associations between visual scores of body structure, precocity and muscling at 550 days of age and growing traits, and verify the possibilities of applying these traits as selection criteria. (Co)variance components were estimated by restricted maximum likelihood, employing an animal model with fixed effects of contemporary group and age as a covariate (linear and quadratic effects). Contemporary groups were defined by variables: sex; year, season and herd of birth; herd and […]