Comparison of boars and castrates for bacon production. 1. Growth data, and carcass and joint composition

Abstract

An experiment was performed to determine whether quality differences between boars and castrates when used for bacon production are true castration effects or due to the greater leanness of boars. Sixty-four commercial hybrid male pigs, half of which were castrated at 10 days of age, were given different levels of feeding so that at 87 kg live weight there was a 2-mm difference in P 2 fat thickness between two groups of 16 boars and two groups of 16 castrates. The leanest group of castrates and the fattest group of boars had similar fat thickness and carcass composition. This design allowed the separation of castration and feeding treatment (carcass composition) effects. Skin thickness and weight (boars greater) and kidney weight (boars heavier) were much more influenced by castration than feeding treatment. Other effects that were more influenced by castration, although less strongly, were killing-out proportion (boars lower because of testes), leg and loin length (boars shorter), joint weight distribution (boars lighter in flank) and lean weight distribution (boars slightly less lean in leg, and more in foreloin and belly). Lean to bone ratio in the side was influenced less by castration than by feeding treatment but boars had more intermuscular fat in relation to subcutaneous fat than castrates. The lean content of the leg was closely related to that of the side, and there were different relationships in boars and castrates. 55

Developmental Comparisons of Boars and Barrows: I. Growth Rate, Carcass and Muscle Characteristics

“…Average daily gain from 4. wk of age to 105 kg was 782 g for boars (combined average daily gain of groups II through V) and 796 g for barrows. No significant differences were found in growth rate to 105 kg, which agrees with data reported by Hines (1966), Newell and Bowland (1972)and Pay and Davies (1973), but differs from the results of Siers (1975) and Wood and Riley (1982). Calculated from their respective regression equation, average daily gain (figure 1) of barrows was 8 Gardiner, NY.…”

Effects of pork differentiation strategies in Canada on pig performance and carcass characteristics

“…Thus, the lower hardness scores observed in carcasses from animals fed the experimental diets (canola and flax) can be explained by the increase in dietary mono-and poly-unsaturated fatty acids (Miller et al 1990;Dugan et al 2001;Caine et al 2007;Juárez et al 2010). Thicker backfat, as observed in heavy carcasses and carcasses from Iberiancrossed pigs, usually leads to higher fat hardness scores, while leaner carcasses have softer fat (Wood and Riley 1982). However, the low hardness scores observed in carcasses from Lacombe-crossed pigs, which contained medium levels of subcutaneous fat, may be linked to different fat compositions due to differences in Lacombe's fat metabolism and deposition.…”

Skull shape in relation to carcass fatness in pigs

“…They were reared as four treatments: boars and castrates receiving a high level of feeding were given 1.4 kg d-1 increasing by 0.2 kg d-1 each week; boars on the low level of feeding received 1.15 kg d-1 increasing by 0.2 kg d-l each week to an upper limit of 1.95 kg d-1; castrates on low intake were given 0.8 kg d-l increasing by 0.14 kg d-1 each week to an upper limit of 1.5 kg d-1. Further details on the rearing conditions are reported by Wood and Riley (1982).7 When the pigs reached approximately 87 kg liveweight they were slaughtered, and one side of each carcass (excluding the head and feet) was physically dissected into fat, muscle and bone.7…”