Spontaneously occurring intramural coronary arteriosclerosis in regularly slaughtered veal calves and beef cattle: a screening study about prevalence and histopathological features.

OBJECTIVES: Intramural coronary arteriosclerosis has been reported in several species, but no systematic studies are currently available in bovine. The present study aimed to describe the arteriosclerotic changes in regularly slaughtered veal calves and beef cattle. ANIMALS: Twenty-five veal calves (6-9 months old) and 17 beef cattle (10-24 months old) housed in intensive livestock farming and regularly slaughtered were included in the present study. METHODS: Selected heart samples were submitted for histopathological and ultrastructural examination and the following parameters were evaluated: intimal hyperplasia, degenerative changes of the tunica media, medial hypertrophy/hyperplasia, myocardial fibrosis, and myocarditis. Pathological intramural coronary arteries with and without lumen narrowing were manually counted in every sample. RESULTS: Intramural coronary arteriosclerosis was observed in all the calves and cattle, with similar prevalence of fibromuscular/muscular intimal hyperplasia (92% vs 88%), degenerative changes of the tunica media (76% vs 71%), and medial hypertrophy/hyperplasia (44% vs 59%). The posterior papillary muscle of the left ventricle was the myocardial localization significantly more affected in both calves (p = 0.0007) and cattle (p = 0.0339). Anitschkow cells were detected in the coronary walls of both calves (60%) and cattle (76%). CONCLUSIONS: This is the first study that systematically describes spontaneously occurring intramural coronary arteriosclerosis in bovine species. Anitschkow cells, whose ultrastructural characteristics and localization suggest their potential origin from the smooth muscle cells of the tunica media of the arteriosclerotic coronary vessels, were also identified.

Different rearing systems for fattening rabbits: Performance and carcass characteristics.

To evaluate the effect of different rearing systems and sex on productive performance and carcass composition and quality, 80 rabbits (40 males and 40 females) of Carmagnola breed were reared from 9 to 16 weeks of age in individual California type cages (0.12m(2)) or in group ground pens (0.25m(2)/head). The animals were kept in standard and uniform environmental conditions and fed the same ad libitum pellet feed. Data on live weight and feed intake were recorded. At the end of the fattening period 10 animals per group were slaughtered and data provided in the World Rabbit Science Association (WRSA) standard method were collected, as well as pH and meat colour. Animals reared in ground pens showed lower productive performances, while, as to slaughtering performances, rabbits reared in cages showed the highest slaughtering weight and also the highest weights for most body parts. Gender slightly affected productive and slaughtering performances: females showed higher feed consumption and higher perirenal fat weight than males. Meat colour parameters showed significant differences in Longissimus lumborum and Biceps femoris due to housing systems and gender effects. In both muscle, rearing system affected pH only 24h after slaughter.

Fatty acid composition of meat and perirenal fat in rabbits from two different rearing systems.

To evaluate the effect of different rearing systems and sex on the fatty acid composition of rabbit meat and perirenal fat, the fat content and fatty acid composition of Longissimus lumborum and perirenal fat were determined by gas chromatography on 40 rabbits (20 males and 20 females) of the Carmagnola Grey breed reared from 9 to 16weeks of age in individual California type cages (0.12m(2)) or in group ground pens (0.25m(2)/head). Ether extract percentage of muscle was significantly influenced by the housing system while, both sex and rearing method affected the fatty acid composition with a decrease in monounsaturated fatty acid (MUFA) and an increase in polyunsaturated ones (PUFA) in penned and male rabbits. The same trends were observed in the fatty acid composition of the perirenal fat, gender only had a significant affect on the saturated fatty acid (SFA) content in the perirenal fat. Indices relating to human health showed the PUFA/SFA ratio to be over the minimum recommendation for rabbits reared in pens and for males, while only the n6/n3 ratio was above the maximum recommendation for caged rabbits. Atherogenic index (AI) of perirenal fat was affected by gender, but no differences were observed in trombogenic index (TI) in either muscle or perirenal fat.

Effect of pre- and post-pubertal castration on Piemontese male cattle. II: Carcass measures and meat yield.

The effect of different castration ages on carcass morphological characteristics, meat yield, commercial cuts and bones weight and measures was evaluated on Piemontese steers and bulls. Carcasses (24) obtained from early castrated (EC, 5th month of age), late castrated (LC, 13th month) and intact males (IM, control group) of similar age (about 18 months) and fattening degree, were weighed, measured and dissected following the local commercial method. Very few differences were found in carcass conformation and fatness as in carcass weight and measures. After data adjusting, few meat cuts were heavier in IM compared to EC and LC, and only one cut measure was different, whereas, almost no differences were found in bone measures and weight. IM produced carcasses with more edible meat than LC and more forequarter and 2nd quality meat than LC and EC. Significant differences were found also between total, hindquarter and perinephric fat.