Scielo RSS <![CDATA[Revista Brasileira de Zootecnia]]> vol. 46 num. 11 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Environment, facilities, and management of hospital pens in growing and finishing pig farms: a descriptive study]]> ABSTRACT The objective of this study was to describe the housing system in the hospital pens on growing and finishing (GF) pig farms. This work was developed by using a questionnaire and was conducted between January and April, 2016. Forty-four GF commercial farms (a total of 41,111 animals) were involved, seeking to raise issues concerning the facilities of the hospital pens, environment, management, feeding and the reasons for transferring the animals to these accommodations. About 98% of the evaluated farms had, at least, one hospital pen. Most of these farms presented a percentage of animals evaluated (PAE) in the infirmary, of less than 1.5% of the total capacity of the animal housing on the farm. In 93.48% of the farms, the criterion used to transfer the animals to the infirmaries was when they were identified as “impaired, hurt, suffering”. In 47.83% of the cases, there were no differences between the hospital and common pens regarding the general management of the animals. The facilities and environment characteristics were similar in almost all hospital pens. Respiratory problems were the main reason for transferring pigs from the common to hospital pens. Under the conditions of this study, sufficient hospital pens exist on farms and overcrowding or competition for resources among pigs are avoided. However, there is no established standard among respondents about where to place the recovered animals. <![CDATA[Comparison of growth curve models in Japanese quail raised in cages enriched with different colored lights]]> ABSTRACT This study compared the growth curve models for the live weight and body length of Japanese quail raised under lights of various colors. The Brody, Gompertz, and von Bertalanffy growth models were used to investigate the effect of different colored lights on Japanese quail growth over a period of six weeks (1-42 days). Four lights of different colors, comprising yellow, red, blue, and white, were used in the study. According to the different light colors, the mean and standard error for the live weight and body length on day 42 were calculated as 196.09 and 3.87 g and 29.48 and 0.192 cm, respectively. Furthermore, while the differences in live weight according to the color of the light being used were statistically significant on days 14, 21, and 28, there were significant differences in body length on days 7, 28, 35, and 42, depending on the color of the light used. The highest values of R2 for body length and live weight were 0.9935 and 0.9988; the lowest sum of square error values for body length and live weight were 9.6588 and 10.6623 according to the Gompertz model. Test results did not reveal autocorrelation among serial data except for those grown under red colored lights. <![CDATA[Effects of crude protein levels on egg quality traits of brown layers raised in two production systems]]> ABSTRACT The objective of this study was the evaluation of egg quality of 30 to 45-week-old brown layers, raised in cages or on floor, supplemented with amino acids, using the ideal protein concept with levels of 14, 15, 16, and 18% crude protein. A total of 400 birds (Hy-sex Brown) were used, distributed into two breeding systems (conventional cage or floor). The evaluated variables were the yolk relative weight, yolk height, albumen relative weight, albumen height, specific gravity, eggshell thickness, and eggshell weight. Treatments consisted of reduced levels of crude protein and were provided to both groups equally. We adopted a completely randomized design, in a factorial scheme, composed of two breeding systems and four levels of crude protein, totaling eight treatments. Five replicates per treatment and 10 birds per experimental unit were used. The breeding system on floor was configured as an option in the breeding of brown layers, of Hy-sex Brown commercial lineage, in the period between the 30th and the 45th week of age, since it presents results equivalent to the ones obtained in the breeding system in cages, having the egg quality as parameter. The system of production on floor is configured as an option in the farming of brown layers, of the commercial lineage Hy-sex Brown. <![CDATA[Impact of piglet birthweight and sow parity on mortality rates, growth performance, and carcass traits in pigs]]> ABSTRACT A total of 5502 piglets from 435 sows were selected for evaluation of the effect of piglet birthweight and sow parity on mortality rate (MR), growth performance, and carcass traits in pigs. Piglets were distributed into one of eight categories according to their weight (&lt;600, 601-800, 801-1000, 1001-1200, 1201-1400, 1401-1600, 1601-1800, and &gt;1801 g) and sows were classified according to parity (1-5). The maximum MR during lactation (day 0 to day 21) was found in category &lt;600 g, whereas the lowest was observed in categories ≥1401 g. Pigs with greater body weight (BW) at birth were equivalently greater until 59 days of age. Average daily weight gain (ADG) was improved by increasing piglet birthweight between 0 and 21 days as indicated by a linear regression effect. After weaning, this effect was reduced up to 168 days, indicated by a quadratic, as opposed to linear, regression effect. The increase in growth rates corresponded to improved lean meat content and hot carcass weight. Increasing sow parity corresponded to a quadratic improvement of BW and ADG during lactation, but not after weaning. However, the improved pre-weaning performance was concomitant with a linear increase of within-litter BW and ADG variation. No effect of parity was observed on carcass traits. Piglet birthweight and sow parity influence litter postnatal development, mainly during early life. After weaning, these effects are less evident with a minor impact on carcass traits. <![CDATA[Comparison of predictive performance of data mining algorithms in predicting body weight in Mengali rams of Pakistan]]> ABSTRACT The present study aimed at comparing predictive performance of some data mining algorithms (CART, CHAID, Exhaustive CHAID, MARS, MLP, and RBF) in biometrical data of Mengali rams. To compare the predictive capability of the algorithms, the biometrical data regarding body (body length, withers height, and heart girth) and testicular (testicular length, scrotal length, and scrotal circumference) measurements of Mengali rams in predicting live body weight were evaluated by most goodness of fit criteria. In addition, age was considered as a continuous independent variable. In this context, MARS data mining algorithm was used for the first time to predict body weight in two forms, without (MARS_1) and with interaction (MARS_2) terms. The superiority order in the predictive accuracy of the algorithms was found as CART &gt; CHAID ≈ Exhaustive CHAID &gt; MARS_2 &gt; MARS_1 &gt; RBF &gt; MLP. Moreover, all tested algorithms provided a strong predictive accuracy for estimating body weight. However, MARS is the only algorithm that generated a prediction equation for body weight. Therefore, it is hoped that the available results might present a valuable contribution in terms of predicting body weight and describing the relationship between the body weight and body and testicular measurements in revealing breed standards and the conservation of indigenous gene sources for Mengali sheep breeding. Therefore, it will be possible to perform more profitable and productive sheep production. Use of data mining algorithms is useful for revealing the relationship between body weight and testicular traits in describing breed standards of Mengali sheep.