Effects of ractopamine hydrochloride and immunological castration in pigs. Part 2: belly quality characteristics and fatty acid composition

Abstract

The effects of immunocastration and ractopamine in the diet on the belly quality were investigated from two crossbred pigs under different conditions of production, diet, management, and slaughter arranged in factorial design using two levels of addition of ractopamine in the diet, 0 and 7.5 ppm, and three genders (gilts, immunocastrated and barrows). The quality of bellies were analyzed for chemical composition, pH, meat and fat color, backfat thickness and fatty acid profile of the fat. The addition of ractopamine showed no significant influence on pH, color and chemical composition in two crossbred pigs. The immunocastrated had thicker belly backfat compared to the bellies of the gilts. The contents of fatty acids polyunsaturated, linoleic, linoleic, arachidonic, total omega 3 and omega 6 were higher for immunocastrated pigs, as well as presenting values greater than 0.4 for the PUFA:SFA ratio, thus, providing bellies with better nutritional quality. The bellies of the gilts and immunocastrated pigs had higher concentrations of iodine value, indicative of higher unsaturated fat content. The results indicated that the addition of ractopamine and immunocastration had little influence on the quality of bellies as well as in their fatty acid profiles, suggesting the continuity of implementation of these techniques.

Influence of Immunocastration and Diet on Meat and Fat Quality of Heavy Female and Male Pigs

“…The reason for it would be in line with the preceding discussion of Trial 1; backfat thickness is generally thinner in IM [ 11 ], and the less developed the backfat, the less is the proportion of MUFA stored in the adipose tissue arising from de novo synthesis [ 37 ]. Mackay et al [ 61 ] and Asmus et al [ 62 ] also found lower total MUFA proportion in the fat of IM, whereas others authors [ 41 , 63 ] failed to detect differences between IM and SCM in this parameter. The lower MUFA content found in IM would be positive from a technological point of view, since MUFA have a negative influence on firmness and cohesiveness of fat tissue [ 64 ].…”

Ractopamine concentration on the lipid profile of swine fat and meat

“…Conversely, PERKINS et al (1992) evaluated the addition of 0, 5, 10, and 20ppm of ractopamine, and observed no effect on any of the evaluated fatty acids. COSTA & SILVA et al (2017) observed only arachidonic acid alteration in backfat when using ractopamine and suggested that the pigs had already formed an outer layer during the time of ractopamine use; consequently indicating that this technology would have a lesser impact on the backfat lipid profile.…”