This paper constitutes an updated review of the production and meat quality aspects of rearing entire male pigs. Since a major obstacle in rearing entire males is the incidence of boar taint, possible methods for detection are also summarised. Safe and fast methods for detection of boar taint would be valuable in avoiding complaints from consumers. Pig meat quality is determined by many aspects, among which odour and taste are the most important attributes. Odour may be negatively affected by the presence of a pheromonal steroid, androstenone, and a fermentation product of L-tryptophan, skatole. Male pigs are surgically castrated in many countries to minimise the risk of accumulation of high levels of androstenone and skatole. Raising entire male pigs is more profitable because they have superior production characteristics and improved meat quality due to leaner carcasses and higher protein content, as compared to castrated pigs. Furthermore, surgical castration is negative from an animal welfare point of view. In most studies, no differences in sensory quality have been found between lean meat from entire male pigs with low levels of androstenone and skatole and pork from castrates and females. The question that remains is: which substances are responsible for boar taint besides androstenone and skatole and whether they need to be considered? The threshold values used for androstenone and skatole might also be too high for highly sensitive persons. Recent research shows that a human odorant receptor, ORD7D4, is involved in sensitivity to androstenone. If the ORD7D4 genotypes of consumer and expert panels are known, this might facilitate consumer studies in the future. There is still a great need for rapid on/at-line detection methods in abattoirs for identifying carcasses with unacceptable levels of boar taint compounds. Several emerging rapid technologies with a potential for boar taint detection have been investigated. They represent various measurement principles such as chemical sensor arrays (electronic noses), mass-spectrometry fingerprinting, ultra-fast gas chromatography, gas-phase spectrometry and biosensors. An industrial detection method should allow 100% correct classification of both acceptable and not-acceptable samples with regard to boar taint sorting criteria. There are, however, still too high a percentage of false negatives ranging from 5% to 20%. In addition, these methods do not yet seem to fulfil the industrial specifications with regard to cost efficiency, simplicity and analysis time. There is still no dedicated measurement technology available for on/at-line detection of boar-tainted carcasses that measures both androstenone and skatole.Keywords: pig meat quality, castration, entire males, detection methods, review ImplicationsBoar taint is the main reason that is preventing the production of entire male pigs in most countries. Across Europe, the majority of male piglets intended for pork production are surgically castrated to avoid potential consumer dissatisfaction because of boar tai...

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Spider monkeys (Ateles spp.) are well known for their highly arboreal lifestyle, spending much of their time in the highest levels of the canopy and rarely venturing to the ground. To investigate terrestriality by Ateles and to illuminate the conditions under which spider monkeys venture to the ground, we analyzed ad libitum data from 5 study sites, covering 2 species and 5 subspecies. belzebuth).Terrestrialism by Ateles at all sites is rare; however, it is more restricted at the 2 South American sites. In South America, ground use only occurred in the contexts of eating soil or rotten wood and visiting salt licks. In contrast at the 3 sites with Ateles geoffroyi it rarely occurred in a feeding context, but instead more frequently while drinking from streams during the dry season, by adult females escaping attack by adult males, and as part of a chase C a m p b e l l e t a l . i n I n t e r n a t I o n a l J o u r n a l o f P r I m a t o l o g y 2 6 ( 2 0 0 5 ) 1040 game. In addition, on BCI adult males were on the ground before attacking adult females. We discuss potential explanations, e.g., climate, species differences, predation pressure, for the differences between the Central/North and South American observations.

An investigation was made to alter the fatty acid composition of pork and a pork product in line with human dietary advice while not adversely affecting factors controlling consumer acceptability. Pigs (n = 150) were assigned to three dietary treatments with 25 intact male-female pairs per treatment. Diet A (control) contained 3% of a 4:1 (wt/ wt) tallow-soybean oil mixture. Diets B and C contained 2% rapeseed oil plus 1% fish oil. Diets A, B, and C were supplemented with 100, 100, and 250 mg of all-rac-alpha-tocopheryl acetate/kg of diet, respectively. Pigs were given ad libitum access to feed from 52 kg live weight until 95 kg (slaughter). Sausages were prepared from the resulting cuts. Tissues of pigs were evaluated in terms of fat firmness, color, fatty acid composition, and contents of alpha-tocopherol and thiobarbituric acid-reactive substances (TBARS). Organoleptic characteristics of chops and sausages were evaluated by a trained taste panel. Pigs fed Diets B and C had improved feed conversion ratios (P < .05) and ADG compared with control pigs. The levels of n-3 (omega-3) polyunsaturates were significantly increased in the tissues and sausage from pigs fed Diets B and C with associated alterations in n-6 to n-3 fatty acid ratios that accorded with contemporary human dietary recommendations. Levels of alpha-tocopherol and TBARS were significantly altered in the tissues. There were no appreciable differences between treatments in carcass characteristics, including color. The overall organoleptic acceptability of chops and sausages was not different between the treatments.

Pigs (n 144, 30 kg liveweight) were allocated to one of three diets differing in the level of whole linseed (Linum usitatissimum, also known as¯axseed). The diets contained 0, 50 and 100 g/kg for diets L0, L50 and L100 respectively, while containing a constant oil content (60 g/kg). Pigs were slaughtered at a liveweight of 77±87 kg. With the exception of a slight difference in feed intake, there was no effect of diet on production characteristics or carcass traits. Levels of a-linolenic acid were increased in all tissues studied as the amount of linseed in the diet increased. In the plasma, m. longissimus thoracis, liver and kidney eicosapentaenoic acid concentration increased markedly. Docosapentaenoic acid concentration increased in the muscle, liver and kidney, whereas in the plasma higher levels of docosahexaenoic acid were observed. None of the longerchain fatty acids (C20 or longer) were detected in the subcutaneous fat. The changes in fatty acid composition resulted in marked changes to the n-6 : n-3 and arachidonic : eicosapentaenoic acid ratios. Feeding whole linseed had no negative effect on the oxidative stability of the meat. Sensory panel results showed no signi®cant differences by diet except for a reduction in abnormal odour (odour perceived by panellists to be abnormal in pigmeat) in the L50 diet and a reduction in the skatole odour (odour of 3-methylindole) in the pigs fed on diet L100. It is concluded that increasing the linseed content of pig diets up to 100 g/kg has no adverse effect on the carcass or meat quality whilst enhancing the levels of n-3 fatty acids which have a potentially positive health effect in man.