Evaluation of Bayesian models for analysis of crude protein requirement for pigs of Brazilian Piau breed

Abstract

We evaluated the inclusion of information on genetic relationship into the analysis of crude protein requirement in diets for pigs of Brazilian Piau breed, using Bayesian inference.The animals were assigned to treatments in a completely randomized design in factorial scheme 4 × 2 (crude protein levels × sex) with 12 repetitions per treatment. The evaluations were carried out in the initial, growing and finishing phases, and after slaughter. The traits evaluated were feed conversion (FC), backfat thickness (BF), daily weight gain (DWG), daily feed intake (DFI) and some carcass cuts. Three models were considered to evaluate the inclusion of information on genetic relationship into the analysis: Model I, a simple linear model; Model II, the same effects of Model I with addition of the independent random effect of animal; and Model III, the same effects of Model II, but including the genetic relationship between the animals. Model III presented the best fit and was considered for later inferences. Crude protein (CP) levels did not significantly influence any of the evaluated traits. The effect of sex was significant only for the growing phase, while its interaction with protein levels presented an opposite result for all evaluated traits. Additionally, CP levels of 10.2 %, 9.6 % and 9.0 % can be used in diets for pigs of Brazilian Piau breed in the initial, growing and finishing phases, respectively.

Effects of Ambient Temperature on the Performance and Thermoregulatory Responses of Commercial and Crossbred (Brazilian Piau Purebred Sires × Commercial Dams) Growing-Finishing Pigs

“…Thus, our findings are in accordance with the previously stated decreased productive performance and high subcutaneous fat of Piau crossbred pigs [ 12 ]. These results were expected since Brazilian native purebred Piau pigs are recognized for their high-fat deposition [ 13 ] and lower growth performance [ 21 ]. Teixeira et al [ 8 ] have reported a reduction of more than 300 g/day in weight gain, an increase of more than 1.5 g/g in feed conversion, and a two-fold higher backfat thickness of Piau purebred pigs compared to commercial genotypes.…”

Depicting latent variables considering different pig genetics and nutritional plans in crossbred pigs

“…Duroc pigs are often referred to as a breed of improved meat quality because they have tender meat and lower drip loss compared with other commercial genetic groups (Peloso et al, 2010;Zhang et al, 2016). Naturalized Brazilian pigs contribute positively for the meat quality (Silva et al, 2019), which may be justified by the higher fatness level in Piau pigs and for the fact that these animals are not under selection (Serão et al, 2011).…”