Practical dietary levels of canola oil and tallow have differing effects on gilt and barrow performance and carcass composition

Abstract

, I. L. 2004. Practical dietary levels of canola oil and tallow have differing effects on gilt and barrow performance and carcass composition. Can. J. Anim. Sci. 84: 661-671. Previously we demonstrated that barrows produced leaner carcasses when fed 5% versus 2% canola oil. The present trial was conducted to determine if the same would be true for gilts or when feeding beef tallow (a source of saturated fatty acids). Four diets were fed (2 or 5% canola oil or digestible energy equivalents of tallow), and 27 gilts and 27 barrows were fed each diet. Experimental diets were fed from 49.4 to 113.5 kg body weight. Barrows fed 2% canola oil had similar average daily gains (ADG) relative to gilts (P > 0.05) fed any diet, but grew slower than barrows fed 5% canola oil (0.99 vs. 1.08 kg d -1 ; P < 0.05) and tended to have lower ADG relative to barrows fed diets containing tallow (P < 0.10). Barrows fed 2% canola oil had poorer feed conversion efficiency (kg feed kg -1 gain) relative to animals fed any other diet (P < 0.05). For barrows, feeding the 2% canola oil resulted in more subcutaneous fat relative to feeding 2.16% tallow (+18 g kg -1 lean cuts; P < 0.05), but the anticipated decrease in barrow subcutaneous fat when feeding 5% canola oil was not significant (-4 g kg -1 lean cuts; P > 0.05). No practical differences in pork quality were noted when feeding any diet, but backfat became more unsaturated when feeding canola oil and led to softer backfat (P < 0.05). When feeding canola oil to barrows, it may therefore be more practical to feed higher levels than lower levels due to improvements in animal performance without changes in body composition, but care must be taken so that fat softness does not become an issue. Les truies nullipares recevant 2 % d'huile de canola enregistrent un gain quotidien moyen (GQM) semblable (P > 0,05) à celui des truies nullipares assujetties à un autre régime, mais elles engraissent plus lentement que les castrats absorbant 5 % d'huile de canola (0,99 c. 1,08 kg par jour; P < 0,05) et leur GQM a tendance à être plus bas que celui des castrats nourris avec du suif (P < 0,10). Les castrats recevant 2 % d'huile de canola valorisent moins bien les aliments (kg de nourriture par kg de poids gagné) que les sujets nourris avec une autre ration (P < 0,05). En ce qui concerne les castrats, la ration renfermant 2 % d'huile de canola accroît plus la proportion de graisse sous-cutanée que celle contenant 2,16 % de suif (hausse de 18 g par kg de viande maigre; P < 0,05), mais la baisse de graisse sous-cutanée qu'on anticipait chez les castrats recevant 2 % d'huile de canola au lieu de 5 % n'est pas significative (baisse de 4 g par kg de viande maigre; P > 0,05). On ne relève aucune variation concrète de la qualité de la viande d'une ration à l'autre, mais le gras dorsal perd de sa saturation et de sa fermeté quand les animaux absorbent de l'huile de canola (P < 0,05). Lorsqu'on sert de l'huile de canola aux castrats, il pourrait donc s'avérer plus commode de leur en donner plus que moins, une conce...

Meat quality and cut yield of pigs slaughtered over 100kg live weight

“…This result was expected and it is consistent with previous reports (Latorre et al, 2003;Suzuki et al, 2003;Dugan et al, 2004). Interaction of sex vs. slaughter weight was observed (P<0.05) on the saturation index, color score, pH 12h of ham and pH 24h of loin.…”

Effects of genotype and dietary oil supplementation on performance, carcass traits, pork quality and fatty acid composition of backfat and intramuscular fat

“…There is little convergence between the results of this study and those of previous studies regarding the effect of gender on pork quality, which are quite variable. However, some responses are consistent across studies, showing that barrows have higher intramuscular fat content than gilts (Candek-Potokar, Monin, & Zlender, 2002;Dugan, Aalhus, Robertson, Rolland, & Larsen, 2004;Ellis, Webb, Avery, & Brown, 1996;Latorre et al, 2003;Suzuki et al, 2003), which was not observed in the present study. The effect of gender on muscle color is not as consistent as its effect on marbling, but higher reflectance values and higher a* and b* values in barrows than in gilts have been reported in some studies (Candek-Potokar et al, 2002;Dugan et al, 2004;Ellis et al, 1996;Latorre et al, 2003).…”

Increasing omega-3 levels through dietary co-extruded flaxseed supplementation negatively affects pork palatability

“…Previous studies have not reported any effect on meat colour when flaxseed was included in pig diets (Bee et al, 2008;Corino et al, 2008;Haak, De Smet, Fremaut, Van Walleghem, & Raes, 2008). However, in the present study, the slight increase in pH 48 h (P = 0.022) after the inclusion of flaxseed in the diet may relate to an increased supply of dietary oil, which may have led to a small increase in fatty acid utilisation at the muscle level and a slight inhibition of initial post-mortem glycolytic rates (Dugan, Aalhus, Robertson, Rolland, & Larsen, 2004). Changes in the glycolytic rate could be related to the effects observed in colour and also to the slight decrease in drip loss (P = 0.043) in meat from pigs fed increasing levels of flaxseed.…”