Effect of various castration protocols on production indicators in pigs: meta-analysis

Abstract

The objective was to evaluate the effect of various castration protocols through a meta-analysis of indicators of daily feed intake, feed conversion, daily weight gain, slaughter weight, hot carcass weight, and carcass yield. 179 publications from three electronic sources (Scopus, PubMed, and Web of Science) were reviewed over a 24-year period, out of which the 26 studies that met the inclusion criteria were selected. The effect was analyzed with six comparisons: C1=surgical castration vs whole; C2=standard immunocastration vs whole; C3= standard immunocastration vs surgical castration; C4= alternative immunocastration vs whole; C5= alternative immunocastration vs surgical castration, and C6= alternative immunocastration vs standard immunocastration. Averages were estimated for feed intake (kg) (0.23, 0.23, -0.05, 0.32, 0.11, -0.09), feed conversion (kg:kg) (0.27, 0.05, -0.16, 0.11, 0.11, 0.11, -0.19), daily weight gain (g) (-9. 54, 39.08, 40.70, 107.63, -53.0, 69.14), carcass weight (kg) (-9.54, 39.08, 40.70, 107.63, -53.0, 69.14), and hot carcass weight (kg) (1.23, 0.85, 0.46, 1.03, 1.02, -0.42) respectively. The indicators of feed consumption, feed conversion, daily weight gain, slaughter weight, and hot carcass weight proved different (P<0.05); only the carcass yield variable exhibited no difference (P>0.05). The conclusion is that immunocastration improves performance in production and carcass indicators; surgical castration improves carcass yield; whole pigs have better feed conversion, and standard and alternative immunocastration differ in their response in terms of production and carcass measurement indicators.