ABSTRACT: The objective was to evaluate the animal production and ingestive behavior of the steers fed different supplements during the growth phase in Aruana grass, and the influence of this supplementation on production performance in feedlot phase. The treatments consisted of three supplements during the growing phase: mineral salt (0.12 g/kg of body weight - BW), low intake energy-protein supplement (1.26 g/kg of BW), and medium intake (3.76 g/kg of BW). Forage canopy characteristics, animal production, and animal behavior on pasture were evaluated in a completely randomized design with three replicates (paddocks). The titanium dioxide marker was used to determine the intake and apparent digestibility during the pasture phase. The production performance in feedlot was evaluated in a completely randomized design with eight replicates (animals). Twenty-four Aberdeen Angus steers (15 ± 1.5 months old; 364.8 ± 21.7 kg BW) were used. At the end of the growth phase the animals were confined and fed a single diet. Dry matter, crude protein, and neutral detergent fiber (NDF) contents of forage and intake were not influenced by the treatments. The average daily gain was higher for the medium intake supplement in pasture phase. The apparent digestibility of NDF (P = and chewing rate were higher for the medium intake supplement. The average daily gain and fat thickness of carcasses were higher for the medium intake supplement in the feedlot phase. The supplements of medium intake increase animal productivity during the growing phase on pastures and cattle’s finishing performance in intensive production systems.

RESUMO: O objetivo deste trabalho foi avaliar a produção animal e o comportamento ingestivo de novilhos alimentados com diferentes suplementos durante a fase de crescimento em capim Aruana, e a influência desta suplementação sobre o desempenho produtivo durante a fase de terminação em confinamento. Os tratamentos consistiram de três suplementos durante a fase de crescimento: sal mineral (0,12 g/kg do peso corporal - PC), suplemento energético-proteico de baixo consumo (1,26 g/kg do PC) e suplemento energético-proteico de médio consumo (3,76 g/kg do PC). As características do dossel forrageiro, a produção animal e o comportamento ingestivo em pastos de capim Aruana foram avaliados utilizando um delineamento inteiramente ao acaso com três repetições (piquetes). O marcador externo dióxido de titânio foi utilizado para determinar o consumo e digestibilidade aparente dos nutrientes na fase de pastagem. O desempenho em confinamento foi avaliado utilizando-se um delineamento inteiramente ao acaso com oito repetições (animais). Vinte e quatro novilhos Aberdeen Angus (15 ± 1,5 meses de idade; 364,8 ± 21,7 kg de peso corporal médio inicial) foram utilizados. Ao final da fase de recria, os animais experimentais foram confinados e alimentados com uma dieta única. Os teores de matéria seca, proteína bruta e fibra de detergente neutro (FDN) da forragem, bem como o consumo destas frações não foram alterados pelos tratamentos. O ganho médio diário foi superior para o suplemento de ingestão média na fase de pastagem. A digestibilidade da FDN e a taxa de ruminação na fase pastagem foram mais elevadas para o suplemento de média ingestão. O ganho médio diário e a espessura de gordura das carcaças foram mais elevados para o suplemento de ingestão média na fase de acabamento em confinamento. Suplementos de ingestão média aumentam a produtividade animal durante a fase de crescimento em pastagens e o desempenho em confinamento de bovinos provenientes de sistemas intensivos de produção.

Resumo: O objetivo deste trabalho foi avaliar o desempenho produtivo e as características da carcaça de cordeiros alimentados com silagens de diferentes tipos de sorgo e milho. Foram utilizados 32 cordeiros machos, da raça Suffolk. O delineamento experimental foi inteiramente casualizado, com quatro tratamentos (silagens) e oito repetições (animais). Foram testadas silagens de sorgo forrageiro GrandSilo, sorgo sacarino BRS 506, sorgo sacarino BRS 511 e milho híbrido duplo BRS 2223. Os cordeiros alimentados com silagens de sorgo apresentaram menor consumo diário de matéria seca que os alimentados com silagem de milho. A dieta contendo silagem de milho proporcionou ganho de peso 27% superior ao dos tratamentos com as demais silagens. A digestibilidade in vivo não diferiu entre as diferentes silagens. Os cordeiros alimentados com silagem de milho apresentaram os menores rendimentos de carcaça quente e fria, de 44,71 e 42,62%, respectivamente, enquanto os que consumiram silagem de sorgo BRS 506 apresentaram os maiores rendimentos de carcaça quente e fria, de 46,90 e 44,78%. O maior consumo e o melhor desempenho dos animais alimentados com silagem de milho não foi suficiente para incrementar a produção e o rendimento de carcaça. Os cordeiros alimentados com silagem de sorgo sacarino BRS 506 apresentam maior eficiência de conversão da silagem em carcaça.

Abstract: The objective of this work was to evaluate the productive performance and carcass traits of lambs fed silages of different types of sorghum and corn. Thirty-two uncastrated male Suffolk lambs were used. The experimental design was completely randomized, with four treatments (silages) and eight replicates (animals). Silages of the GrandSilo forage sorghum, BRS 506 saccharine sorghum, BRS 511 saccharine sorghum, and the BRS 2223 double-grain corn hybrid were tested. The lambs fed sorghum silages had a lower daily dry matter intake than those fed corn silage. The diet containing corn silage led to 27% greater weight gain, when compared with the treatments with the other silages. In vivo digestibility did not differ among the different silages. Lambs fed corn silage showed the lowest hot and cold carcass yields of 44.71 and 42.62%, respectively, whereas those that consumed BRS 506 sorghum silage showed the highest hot and cold carcass yields of 46.90 and 44.78%. The greater intake by and the better performance of the animals fed corn silage was not enough to enhance production and carcass yield. Lambs fed BRS 506 saccharine sorghum silage have higher efficiency in the conversion of silage into carcass.

ABSTRACT This study evaluated morphometric and ultrasound information of tilapia (O. niloticus) breeders through multivariate analysis. We applied correlation, clustering, and principal component analysis to a dataset composed of information from 222 male and female breeders of the improved GIFT strain. The body weight, objective of the breeding program, showed a high positive correlation with most of the morphometric parameters. The formation of clusters indicated characteristics responsible for muscle composition and carcass weight. Some characteristics showed a high correlation, such as body weight and fillet weight (0.98 and 0.94 for females and males, respectively), and a high contribution to the explanation of data variability; of the total characteristics evaluated for females, two explained 75% data variability and four explained 72% for males. We concluded that it is possible to reduce the number of characteristics measured, as well as use information of average daily weight gain and body weight to select female and male breeders, respectively, to drive genetic gains favoring more productive generations.

ABSTRACT: The composting of laying hen manure is an efficient way of treating waste and producing an organic fertilizer with excellent characteristics; however, the high N losses reduce its concentration in the resulting fertilizer. Associating this residue with crude glycerin (CG) promotes a better C:N ratio and contributes to higher N retention during composting, with improvements in solids reduction and production of organic fertilizer with higher concentration of this nutrient. We carried out this research considering the hypothesis that adding CG – a byproduct of biodiesel production – to laying hen waste composting provides better N retention in the fertilizer generated. Increasing CG doses (0, 3, 6, 9, and 12 % in relation to the fresh mass in the windrows) were added to the laying hen manure with windrows composted for 70 days. A reduction by 100 % in total and thermotolerant coliforms occurred at all levels of CG addition. The maximum reductions in total (TS) and volatile (VS) solids were 64 and 76 %, respectively, and occurred with the addition of 6 % CG. The windrows that did not receive CG had higher N losses during the process (32 %) while the highest N concentration in the compost was 5 % at 6 % CG. We identified that adding 6 % CG to the laying hen manure in co-composting increases the reductions in TS and VS and provides higher N retention, which improves the quality of the organic fertilizer.

ABSTRACT The objective of this study was to evaluate the behavior of immunocastrated male pigs compared with females and castrated males during the period before and after full immunization. A total of 30 animals were divided into three treatments, with ten animals in each (females, barrows, and immunocastrated males). The experiment was divided into three periods: 70 to 80 days of age (period 1), 81 to 110 days of age (period 2), and 111 to 140 days of age (period 3). The behavior of animals during these stages was evaluated. Immunocastrated males showed a higher rate of aggressive and sexual behavior during period 2, which decreased after the second vaccine dose. Both barrows and immunocastrated males presented high locomotion in period 1, reducing the frequency of this activity in period 3. All analyzed animals had a higher level of activities such as drinking, playing, and sexual behavior in period 1 than in the other periods, decreasing during the experiment. The remaining behavioral responses did not differ between the studied categories. Immunocastrated males had higher proportions of undesirable behaviors (aggressive and sexual) related to the surgically castrated males and females, and these were reduced after the second vaccine dose. Immunocastration is effective in the reduction of behaviors such as agonistic and sexual at the same levels observed in females and surgically castrated males. However, immunocastrated pigs are more subject to these undesirable behaviors before full immunization.

RESUMO: Objetivou-se determinar a variação genética na produção de leite, seus constituintes e características reprodutivas. Foram utilizadas 9.318 lactações de 3.061 búfalas para estimar as herdabilidades das características produção de leite (PL), porcentagem de gordura (%G), porcentagem de proteína (%P), duração da lactação (DL), intervalo entre partos (IEP) e idade ao primeiro parto (IPP), além das correlações genéticas e fenotípicas entre as mesmas. Os componentes de covariância foram estimados por inferência Bayesiana em análises multicaracterísticas utilizando um modelo animal e o programa computacional GIBBS2F90. Foram incluídos os grupos de contemporâneos e o número de ordenhas (1 ou 2) como efeitos fixos, a idade da búfala ao parto (efeitos linear e quadrático) como covariáveis e os efeitos genético aditivo, ambiental e residual como efeitos aleatórios. As estimativas da herdabilidade e seus desvios-padrão para PL, %G, %P, DL, IEP e IPP foram 0,24±0,02; 0,34±0,05; 0,40±0,05; 0,09±0,01; 0,05±0,01 e 0,16±0,04, respectivamente. As correlações genéticas entre a PL e %G, %P, DL, IEP e IPP foram -0,29; -0,18; 0,66; 0,08 e 0,24, respectivamente. A produção de leite e seus constituintes apresentaram variação genética suficiente para obtenção de ganhos genéticos pela seleção. As correlações genéticas entre produção de leite e seus constituintes foram negativas, e portanto, os esforços para aumentar a PL pode diminuir a qualidade do leite. As reprodutivas apresentaram pouca influência genética, indicando que melhorias no manejo seriam suficientes para obter melhores desempenhos.

ABSTRACT: The objective of this study was to determine the genetic variation in milk production, milk components, and reproductive traits in dairy buffaloes. A total of 9,318 lactation records from 3,061 cows were used to estimate the heritability of milk yield (MY), fat percentage (%F), protein percentage (%P), lactation length (LL), calving interval (CI), and age at first calving (AFC), as well as genetic and phenotypic correlations between these traits. Covariance components were estimated by Bayesian inference in a multitrait animal model using the GIBBS2F90 program. Contemporary groups and number of milkings (1 or 2) were included as fixed effects, age of dam at calving (linear and quadratic effects) as a covariate, and additive genetic, permanent environmental, and residual effects as random effects. The heritability estimates (± standard deviation) were 0.24 ± 0.02, 0.34 ± 0.05, 0.40 ± 0.05, 0.09 ± 0.01, 0.05 ± 0.01, and 0.16 ± 0.04 for MY, %F, %P, LL, CI, and AFC, respectively. The genetic correlations between MY and %F, %P, LL, CI, and AFC were -0.29, -0.18, 0.66, 0.08, and 0.24, respectively. Milk production and milk components showed sufficient genetic variation to obtain genetic gains through selection. The genetic correlations between MY and milk components were negative, and thus, undesirable because efforts to increase MY may decrease milk quality. Reproductive traits had little genetic influence, indicating that improvement of management would be sufficient to obtain better performance.

O objetivo deste trabalho foi comparar modelos de regressão aleatória para a estimação de parâmetros genéticos da produção de leite de Guzerá, com uso dos polinômios ortogonais de Legendre. Foram utilizados 20.524 registros da produção de leite no dia do controle (PLDC) de 2.816 vacas da raça Guzerá em primeira lactação. Agrupadas em 10 classes mensais, as PLDC foram analisadas quanto aos efeitos genéticos aditivos, e aos de ambiente permanente e residual (efeitos aleatórios); enquanto efeitos de grupo de contemporâneos, covariável idade da vaca ao parto (efeito linear e quadrático) e a curva média de lactação foram analisados como efeitos fixos. Trajetórias quanto aos efeitos aditivos genéticos e de ambiente permanente foram modeladas por meio de uma função de covariância com uso do polinômio de Legendre de segunda à quinta ordem. As variâncias residuais foram consideradas em 1, 4, 6 ou 10 classes de variância. O melhor modelo teve seis classes de variância residual. As estimativas de herdabilidade para os registros de PLDC variaram de 0.19 a 0.32. O modelo de regressão aleatória que utilizou o polinômio de Legendre de segunda ordem, quanto ao efeito genético aditivo, e o polinômio de quinta ordem, quanto ao efeito de ambiente permanente, é o mais adequado para a comparação dos principais critérios utilizados. O modelo que utilizou o polinômio de Legendre de segunda ordem, quanto ao efeito genético aditivo, e o de quarta ordem, quanto ao efeito de ambiente permanente, pode ser utilizado nestas análises.

The objective of this work was to compare random regression models for the estimation of genetic parameters for Guzerat milk production, using orthogonal Legendre polynomials. Records (20,524) of test-day milk yield (TDMY) from 2,816 first-lactation Guzerat cows were used. TDMY grouped into 10-monthly classes were analyzed for additive genetic effect and for environmental and residual permanent effects (random effects), whereas the contemporary group, calving age (linear and quadratic effects) and mean lactation curve were analized as fixed effects. Trajectories for the additive genetic and permanent environmental effects were modeled by means of a covariance function employing orthogonal Legendre polynomials ranging from the second to the fifth order. Residual variances were considered in one, four, six, or ten variance classes. The best model had six residual variance classes. The heritability estimates for the TDMY records varied from 0.19 to 0.32. The random regression model that used a second-order Legendre polynomial for the additive genetic effect, and a fifth-order polynomial for the permanent environmental effect is adequate for comparison by the main employed criteria. The model with a second-order Legendre polynomial for the additive genetic effect, and that with a fourth-order for the permanent environmental effect could also be employed in these analyses.

The objectives of this study were to estimate the genetic parameters for milk yield unadjusted and adjusted for days in milk and, subsequently, to assess the influence of adjusting for days in milk on sire rank. Complete lactations from 90 or 150 days of lactation to 270 or 350 days in milk were considered in these analyses. Milk yield was adjusted for days in milk by multiplicative correction factors, or by including lactation length as a covariable in the model. Milk yields adjusted by different procedures were considered as different traits. Heritability estimates varied from 0.17 to 0.28. Genetic correlation estimates between milk yields unadjusted and adjusted for days in milk were greater than 0.82. Adjusting for days in milk affected the parameter estimates. Multiplicative correction factors produced the highest heritability estimates. More reliable breeding value estimates can be expected by including short length lactation records in the analyses and adjusting the milk yields for days in milk, regardless of the method used for the adjustment. High selection intensity coupled to the inclusion of short length lactations and adjustment with multiplicative factors can change the sire rank..

The objective of the present study was to estimate genetic parameters for test-day milk, fat and protein yields and 305-day-yields in Murrah buffaloes. 4,757 complete lactations of Murrah buffaloes were analyzed. Co-variance components were estimated by the restricted maximum likelihood method. The models included additive direct genetic and permanent environmental effects as random effects, and the fixed effects of contemporary group, milking number and age of the cow at calving as linear and quadratic covariables. Contemporary groups were defined by herd-year-month of test for test-day yields and by herd-year-season of calving for 305-day yields. The heritability estimates obtained by two-trait analysis ranged from 0.15 to 0.24 for milk, 0.16 to 0.23 for protein and 0.13 to 0.22 for fat, yields. Genetic and phenotypic correlations were all positive. The observed population additive genetic variation indicated that selection might be an effective tool in changing population means in milk, fat and protein yields.

Considerando que el recuento de células somáticas (RCS) de muestras de leche es una valioso indicador de la salud de la ubre de búfalas, se desarrolló el presente trabajo con el fin de estimar la relación existente entre algunos factores ambientales y el RCS, verificando la frecuencia de ocurrencia de muestras analizadas en clases de recuentos muy altos, altos, medios y bajos. Fueron analizadas informaciones de 23.534 muestras de controles de leche (RCS), referentes a 2.198 lactancias de animales de la raza murrah con edades entre los dos y quince años, hijas de 187 reproductores; estos muestreos fueron realizados durante siete años. Los resultados indicaron que de manera general, ocurrieron bajos, medios, altos y muy altos RCS para, 96,34%, 2,3%, 0,96% y 0,4% de las muestras, respectivamente. Las clases de bajos y medios RCS, fueron las que presentaron las mayores frecuencias, confirmando que en búfalos, hay una tendencia a menores recuentos que en los bovinos. Se presentaron diferencias entre las medias del RCS por orden de parto y por estación de parto, y hubo diferencias estadísticamente significativas (P < 0,05) para las medias del RCS en algunos controles. En relación con el orden de parto fueron observadas diferencias entre las frecuencias de los RCS, siendo que, de modo general, a medida que aumentó el orden del parto, disminuyó el porcentaje de bajos recuentos y aumentaron las frecuencias de recuentos medios, altos y muy altos. Los resultados indicaron que los efectos de hacienda, año y orden de parto deben ser considerados en la comparación entre animales.

This study was performed in order to estimate the relation between some environmental factors and somatic cell count (SCC). This relation was verified by testing the frequency of analyzed samples in classes according to the SCC as follows: very high, high, medium and low. 23,534 milk samples corresponding to 2.198 lactations of Murrah breed animals were used. The buffaloes were between 2 and 15 years old and were daughters of 187 males. The samples were taken during a period of 7 years. In general, the results showed that SCC was low, medium, high and very high for 96.34%, 2.3%, 0.96% and 0.4% for the samples, respectively. Low and medium SCC had the highest frequencies, pointing out that in buffaloes there is a tendency of lower SCC when compared to bovines. There were differences between the average SCC according to the order and season of parturition. There were also significant differences between the average SCC of some control samples (P<0.05). In relation to order of parturition there were observed differences between SCC frequencies, but as a general statement it was observed that as order of parturition was higher the rate of lower SCC decreased and the frequency of medium, high and very high SCC increased. The results indicated that the effects of farm, year and order of parturition should be considered when comparing animals