Scielo RSS <![CDATA[Revista Brasileira de Zootecnia]]> vol. 45 num. 10 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Digestibility of animal and vegetable protein ingredients by pirarucu juveniles, <strong> <em>Arapaima gigas</em></strong>]]> ABSTRACT The objective of this study was to determine the apparent digestibility coefficients of energy, protein, and amino acids in protein ingredients by pirarucu juveniles. A test was conducted with six protein ingredients: meat and bone meal, fish meal, hydrolyzed feather meal, poultry by-product meal, soybean meal, and corn gluten meal. Three repetitions were used for each tested ingredient. A reference feed was used with 430 g kg−1 crude protein and 19.63 kJ g−1 gross energy. The test feeds consisted of the replacement of 30% of the reference feeds with the test ingredients. Chromium oxide was added to the feeds at 1 g kg−1 as an external marker. Eighteen juveniles with an average weight of 235±36 g were used. The best apparent digestibility coefficients of protein were found for fish meal, followed by the poultry by-product meal and meat and bone meal. However, except for gluten, all the tested ingredients presented protein digestibilities above 0.70. The crude energy apparent digestibility coefficient was higher for animal ingredients, above 0.75, than for vegetable ingredients, which presented values below 0.60. Pirarucu efficiently uses the protein from the tested ingredients, regardless of origin. However, it has a preferential ability to use the energy from animal ingredients. <![CDATA[Management of consecutive cuts in the production and quality of wintergreen paspalum seeds]]> ABSTRACT The objective of this study was to evaluate the practice of consecutive cuts in the production and quality of Paspalum guenoarum seeds of the "Azulão" ecotype. The experimental design used was in completely randomized blocks with four replications. The treatment included three cuts in succession: zero cut, one cut, two cuts, and three cuts. The variables were: number of total tillers/plant; number of vegetative tillers/plant; number of reproductive tillers/plant; percentage of reproductive tillers; number of racemes/inflorescence; weight of thousand seeds; number of seeds/inflorescence; seed production; forage dry matter; water content of seeds; germination; first germination count; and germination speed index. The largest seed production was obtained with zero cut (850.3, first year and 719.4 kg/ha-1, second year) and one cut (794.4, first year and 627.3 kg/ha-1, second year) with no statistical difference between them. The largest germination percentage was seen with the application of zero (71.0%, first year and 79.3%, second year) and one cut (69.3%, first year and 75.0%, second year). There was a decrease in the production and quality of the seeds of the second cut, especially during the first year of evaluation. The total tillers, the percentage of tillers that went through the reproductive stage, and the number of reproductive tillers are the variables that are most highly correlated with seed production. <![CDATA[Effects of ensiling density on nutritive value of maize and sorghum silages]]> ABSTRACT Studies were conducted to determine the effects of different ensiling densities on fermentation, aerobic stability, and nutritive value of maize and sorghum silages. Maize and sorghum were harvested at dough (363 g/kg) and milk stages (275 g/kg), respectively. Herbages were chopped approximately 1.5 cm after harvest and then ensiled in mini silos at high and low-bulk densities for 8.5 weeks. Different bulk densities were achieved by ensiling different weights of herbage in the fixed-volume mini silos (1.5-L anaerobic jars, Weck, Germany). The obtained dry matter (DM) densities were 168 and 216 kg of DM/m3 for maize forage and 132 and 178 kg of DM/m3 for sorghum forage. Fermentation kinetics, the rate of aerobic deterioration upon aerobic exposure, and nutrient digestibility were followed during the periods of ensiling (on days 2, 4, 8, 15, and 60). In all cases, increased packing density resulted in silages with lower acetate content, ammonium N levels, and fermentation losses, but lactate content did not differ. Butyrate was detected in appreciable amounts only in sorghum silage. Propionate was not detected in any silage. Tightly packed silages remained stable upon exposure to air. Tight packing increases the digestibly of nutrients and improves the energy content of silages. These data show that high density limits air infiltration and reduces the oxidation loss during storage and feed-out. As a consequence, more dry matter is recovered and more energy is preserved. <![CDATA[Study on the polymorphism of POU1F1 gene in sheep]]> ABSTRACT In this study, POU1F1 gene polymorphism was detected in five sheep populations (large-tailed Han, small-tailed Han, Yuxi fat-tailed, Lanzhou large-tailed, and Mongolian sheep), using DNA pooling and sequencing, to provide theoretical basis for the breeding of excellent sheep varieties. Three single-nucleotide polymorphism (SNP) loci of POU1F1 gene were detected in five sheep populations, namely C355T (C/T), C71G (C/G), and C330G (C/G). C and T frequencies of C355T were 0.67/0.33, 0.81/0.19, 0.67/0.33, 1.00/0.00, and 0.93/0.07, respectively, in large-tailed Han, small-tailed Han, Yuxi fat-tailed, Mongolian, and Lanzhou large-tailed sheep. C of C355T locus was the dominant allele in five sheep populations. C and G allele frequencies of C330G locus were detected in Yuxi fat-tailed sheep; their frequencies were 0.75 and 0.25, respectively. C and G allele of C71G locus were only detected in Yuxi fat-tailed and large-tailed Han sheep; their frequencies were 0.87/0.13 and 0.87/0.13, respectively. The cluster analysis based on POU1F1 gene sequence showed that bactrian camel, dromedary, and wild camel clustered first, and dolphin and killer whales clustered according to taxonomy. Although the four species Tibetan antelope, buffalo, goat, and sheep were alone, they got close and the relative genetic relationship was intimate according to the dendrogram. The mutation site analysis of the POU1F1 gene in five sheep populations in this study would be favorable for uncovering the function of POU1F1 gene deeply. <![CDATA[Relationships between physiological and behavioral responses of goat bucks in mating season]]> ABSTRACT The objective of this study was to determine the sexual parameters in young bucks with different sexual activity and the effect of experience (age) on sexual parameters in bucks. Fifteen young, sexually inexperienced (SI) and five adult, sexually experienced (SE) Saanen × Hair goat crossbred bucks were used in this study. Bucks were individually exposed to three estrus does for 15-min periods during four sexual performance tests, which were carried out every other day to determine some sexual behavior traits such as flehmen response, reaction time, and ejaculation efficiency. Sexually inexperienced young bucks were evaluated based on their sexual activity (active (AC) vs inactive (IA)) and presence of horn. It was found that AC bucks had significantly higher serum testosterone concentrations (31.5 vs 21.5 ng/mL) and weight loss (114.2 vs 51.2 g/day) than IA bucks. In addition, weight loss was significantly correlated with ejaculation efficiency in young bucks. On the other hand, horned bucks tended to have higher ejaculation efficiency with significantly longer reaction time than polled bucks. For experience (age) classes, SE bucks had higher testosterone concentration (76.0 vs 31.5 ng/mL) and weight loss (16.7 vs 8.6%) than SI active young bucks. However, the effect of experience on other sexual performance traits was found to be limited. Overall, these results indicate that testosterone concentration may affect sexual performance of young bucks in the mating season. Age-related sexual experience is not a determining factor for sexual performance in bucks. However, sexual performance data alone may not reflect reproductive outcomes without semen data. <![CDATA[The effect of supplementing sow and piglet diets with different forms of iron]]> ABSTRACT The objective of this study was to evaluate the effect of chelated iron supplementation on gestating and lactating sows and on their suckling and weaned piglets. Reproductive traits, piglet performance, hematological parameters, and the iron concentrations in colostrum, milk, and stillborn livers were measured. Ninety-six sows were subjected to one of three treatment groups. Group T1 comprised pregnant and lactating sows treated with diets supplemented with inorganic iron (551 mg Fe/kg) and suckling piglets administered 200 mg of injectable iron dextran. Group T2 was the same as T1, except that sows after 84 days of gestation, lactating sows, and suckling piglets were fed a diet supplemented with 150 mg Fe/kg of chelated iron, and suckling piglets were administered injectable iron dextran. Group T3 was the same as T2 but without injectable iron dextran for suckling piglets. During the nursery phase, all of the weaned piglets were penned with their original groups or treatments and received isonutritive and isocaloric feeds. Piglets from the T2 and T3 groups also received an additional 150 mg Fe/kg of chelated iron via their feed. There were no differences among the treatments for reproductive traits or the iron concentrations in the colostrum, milk, or liver. The piglets that did not receive the injectable iron dextran showed the poorest performance during the pre-and post-weaning phases and showed the poorest hematological parameters of the suckling piglets. The chelated iron supplementation is insufficient to meet piglet demand. The iron dextran supply is necessary for suckling and weaned piglets. <![CDATA[Effect of different levels of alpha tocopherol on performance traits, serum antioxidant enzymes, and trace elements in Japanese quail (<strong> <em>Coturnix coturnix japonica</em></strong> ) under low ambient temperature]]> ABSTRACT This study was designed to find the effect of vitamin E supplementation on growth, serum antioxidant enzymes, and some trace elements in Japanese quail (Coturnix coturnix japonica) under low ambient temperature. A total of 180 day-old Japanese quails were randomly divided into four groups and provided with 0 (group A), 50 (group B), 100 (group C), and 150 IU/kg (group D) vitamin E (dl-α-tocopherol acetate) under an average temperature of 9±0.5 °C for an experimental period of 42 days. The result showed that feed intake per day, body weight, weight gain per day, and feed conversion ratio did not differ significantly between the groups. Serum concentrations of superoxide and glutathione peroxidase were significantly high in birds supplemented with 150 mg/kg of vitamin E. The concentration of aspartate aminotransferase was not significantly affected between the control and treated groups; however, alanine transaminase concentration significantly reduced in group D. Zinc concentration in the blood increased significantly in group D, with no significant effect on copper and manganese between the control and treated groups. Vitamin E at the level of 150 IU/kg of feed improves the blood antioxidant status and zinc concentration, with no effect on the performance traits of quail reared under low ambient temperature. <![CDATA[Free amino acid profile of <strong> <em>Bubalus bubalis</em></strong> L. meat from the Campania region]]> ABSTRACT In this study, we determined the amount of carnosine and anserine in water buffalo meat without hanging treatment and the free amino acid profile by using amino acid analyser with post-column ninhydrin derivatization procedure. The main free amino acids present in samples were glutamic acid (&gt;60 mg/100 g), followed by alanine, glycine, and arginine. Other protein amino acids were detected in minor amounts (less than 2 mg/100 g). Among the non-protein amine-containing compounds, taurine and urea were the most abundant. The analysis showed that 50% of the total free amino acids was represented by dipeptides carnosine (average ~130.3 mg/100 g) and anserine (average ~17.9 mg/100 g). Thus, this study for the first time reports the free amino acids profile of water buffalo meat and the content of carnosine and anserine, potentially involved in the darkening meat process and their ratio, that could be used to estimate the water buffalo meat portion in mixed meat products. <![CDATA[Factors affecting the selling prices of calves in auctions in Santa Catarina State, Brazil]]> ABSTRACT The objective of this study was to investigate the effects of genetic group and calf sex on selling prices in auctions in the state of Santa Catarina (SC), Brazil. We evaluated 33,143 animals, representing 3,587 lots in 47 auctions from 2009 to 2014. The calves were classified according to genetic groups: British breed or crossbreed (BX); Continental breed or crossbreed (CX); Zebu breed or crossbreed (ZC); British and Continental crossbreed (BC); and Bos taurus and Bos indicus crossbreed (TI). The lots were composed of male and female calves. The years presenting low and high changes in the price of calves were similar to the variation in the price of beef cattle and, in 2014, the calf price reached its highest value (R$5.36). Male calves were sold at prices higher than female calves (average 7.8%), but this difference was driven by year of analysis, in which the closest approach occurred during periods of reduction in the price of live cattle in SC (2012 and 2013). Calves of genetic groups ZX and TI received, on average, lower prices (R$4.49 and R$4.64, respectively) compared with the other groups. In 2013, males from the BX group had greater variation in price compared with CX (3.9%) and BC (5.7%). On the other hand, female heifers from the BX group received higher average prices in 2011 compared with the CX, BC, IT, and ZX groups (8.1, 8.5, 14.7, and 16.5%, respectively). Recently, female British heifers have had a greater appreciation in auctions held in SC, possibly for their reproductive performance potential of beef cows. Thus, sex and different genetic groups are factors that impact the selling price of calves in the SC region. <![CDATA[Prediction of weight and percentage of salable meat from Brazilian market lambs by subjective conformation and fatness scores]]> ABSTRACT This study assessed the use of conformation and fatness scores of the EUROP sheep carcass grading system to predict weight and percentage of salable meat from Brazilian market lambs. Data were collected from in vivo, carcass, and retail production from 252 uncastrated lambs. Evaluated models included single regressions, two multivariate models, and one determined by the stepwise procedure. Conformation was moderately correlated with weight of salable meat. Fatness scores were correlated with rump perimeter, carcass width, and thoracic depth with coefficients of −0.33, −0.32, and −0.23, respectively. Body weight was the best single predictor for weight of salable meat and cold carcass yield for percentage of salable meat. All multivariate models for weight of salable meat prediction were significant. Stepwise regression with body weight, leg perimeter, thoracic depth, rump perimeter, and fatness scores predicted 98% of weight of salable meat variation. For percentage of salable meat prediction, stepwise regression with cold carcass yield, leg perimeter, and conformation score was significant. The EUROP conformation and fatness scores can be used in Brazil for the prediction of lamb meat production.