Affordable Access

Publisher Website

Modeling nutritional and performance factors that influence the efficiency of weight gain in relation to excreted nitrogen in weaning piglets.

  • Cardinal, K M1
  • Vieira, M S1
  • Warpechowski, M B2
  • Zielgelmann, P K3
  • Montagne, L4
  • Andretta, I1
  • Ribeiro, A M L1
  • 1 Department of Animal Science, Federal University of Rio Grande do Sul,Porto Alegre, RS 91540-000,Brazil. , (Brazil)
  • 2 Department of Animal Science, Federal University of Paraná,Curitiba, PR 80035-050,Brazil. , (Brazil)
  • 3 Department of Statistic, Federal University of Rio Grande do Sul,Porto Alegre, RS 91509-000,Brazil. , (Brazil)
  • 4 INRA/AgrocampusOuest, UMR 1079, Systèmes d'Elevage, Nutrition Et Humaine,F. 35000 Rennes,França.
Published Article
Animal : an international journal of animal bioscience
Publication Date
Jul 19, 2019
DOI: 10.1017/S1751731119001587
PMID: 31322100


One of the most debated topics in pig production is the need to study, understand and change the production system in order to improve nutrient efficiency, becoming more environmentally friendly. The nitrogen excretion has highly deleterious effects on the environment, and it is necessary to develop tools that help to reduce the excretion of this compound without compromising productivity. Therefore, two models were generated to estimate the efficiency of weight gain in relation to excreted nitrogen in post-weaning piglets. Data for testing these models were obtained from previous master and PhD studies carried out at the Federal University of Rio Grande do Sul, Animal Science Laboratory using piglets in the post-weaning phase with results for performance and digestibility. The database that was constructed was composed of raw data from 10 studies carried out between 2000 and 2016, on a total of 726 piglets weaned at ages between 17 and 28 days, and to which 62 different treatments were applied. An exploratory analysis of the data was done by evaluating scatter plots and histograms, and variables representing different treatments were used in a stepwise multiple linear regression analysis, with the F-test used as the selection criterion. Two models were generated that either considered the nitrogen retained or not, to estimate the ratio between weight gain and excreted nitrogen using generalized linear model procedure. The authors analyzed the behavior of each variable to evaluate whether the equation generated was biologically coherent. Weight gain, dry matter intake, nitrogen intake, metabolizable energy intake, retained nitrogen and urinary nitrogen were all significant (P<0.001) variables in model I, and in model II the variable fecal nitrogen was also included. The models had high coefficients of determination (R 2 of model I and II were 0.9013 and 0.8271, respectively), and the nitrogen ingested variable was the one that most strongly influenced growth efficiency. When the retained nitrogen variable was removed from the model, there was a reduction in the fit of the equations. It was possible to conclude that both of the two models generated could be applied and the amount of nitrogen ingested had the greatest influence on growth efficiency related to nitrogen excretion.

Report this publication


Seen <100 times