An investigation of slaughter weight and muscle type effects on carcass fatty acid profiles and meat textural characteristics of young Holstein Friesian bulls.

Study objectives included the assessment of carcass fatty acid composition and meat texture characteristics of younger Holstein Friesian bulls. Three experimental groups were formed based on the weights of the 23 young bulls at slaughter: lighter, medium, and heavier. Samples were taken from the Gluteus medius (GM) and Longissimus thoracis muscles 24 h after slaughter. Fatty acid composition, Warner-Bratzler Meat Shear (WBS) measurements, as well as textural profile analysis (TPA) and sensory analysis of the muscle samples were conducted. The fatty acid composition was determined using Thin Layer Chromatography (HPTLC). Polyunsaturated fatty acids and dietary fatty acids give a neutral hypocholesterolemic effect in direct fluorescent antibody (DFA) contents, DFA/OFA (C14:0+C16:0) ratio, hardness, Warner-Bratzler Shear force and also the chews number - which is desirable - before swallowing (NCBS) the meat were significantly decreased with the increasing slaughter weight. Higher slaughter weight resulted in a larger amount of beef with a better panel tenderness score; however, the meat obtained from the LSW group was less healthy considering the fatty acid profile. Additionally, internal fat contained the highest saturated fatty acids concentrations, while subcutaneous fat contained the highest amount of monounsaturated fatty acids. Furthermore, intramuscular fat levels were highest in PUFA and PUFA/SFA ratio. As a result, this study strongly suggests that slaughter weight and anatomical location of fat samples contribute significantly to meat texture characteristics and fatty acid profiles in Holstein Friesian bulls.

Effects of flooring types on teat end bacteria counts, milk quality, hygiene and behaviour of dairy cows housed in tie-stall closed barn.

This study aimed to investigate environmental mastitis causing bacteria counts in the teat end, somatic cell counts (SCC) of milk samples, cleanliness scores and behavior of cows kept on concrete and rubber mat floorings. For this purpose, 19 Holstein-Friesian dairy cows were allocated into concrete and rubber mat groups. Swab samples were taken from the teat ends to determine the bacterial counts causing environmental mastitis. Milk samples were collected from a composite of all four quarters to determine the SCC. Instantaneous sampling method was utilized to observe the behavioral activities of cows. Cows were visually evaluated to determine the udder cleanliness score. Independent samples t-test was utilized in the statistical analysis of the obtained data. Coliform (P<0.05), Escherichia coli, and Klebsiella spp. (P<0.01) counts of the swab samples taken from the cows housed on concrete flooring were significantly higher than rubber mat group. However, no statistically significant differences were found between groups in terms of total bacteria, Streptococcus spp., and Enterobacteriaceae counts. The SCC on samples taken from cows kept on concrete surface were significantly higher (P<0,05) than that of animals housed on rubber mat. Furthermore, cows in the rubber mat group were determined to be significantly cleaner (P<0.05) than those in concrete group. It was also determined that the cows housed on rubber mat spent significantly longer time for lying behavior (P<0.05), which is a significant indicator of animal comfort. The time spent for standing without eating was considerably higher (P<0.01) in concrete group. In addition, the times spent for eating was significantly lower (P<0.01) in the concrete group. It was concluded that, using rubber mat instead of concrete for flooring in tie-stall barns decreases the contamination of environmental mastitis pathogens, increases milk quality and cow cleanliness score as well as animal comfort and welfare.

Effects of Slaughter Age of Holstein Friesian Bulls on Meat Quality: Chemical Composition, Textural Characteristics, Sensory Attributes and Fatty Acid Profile.

This study aimed to investigate the effects of slaughter age (young vs. old), muscle type (Longissimus dorsi (LD), Gluteus medius (GM)) and fat deposits (kidney knob and channel fat, subcutaneous fat, intramuscular fat) on chemical, organoleptic, textural characteristics and fatty acid composition of Holstein Friesian bull meat. For this purpose, the carcasses of 26 Holstein Friesian bulls that had been fattened on the same private farm were assigned to two experimental groups based on their age at slaughter: a young group (YG) (average age: 17.0 ± 1.0 months old) and an old group (OG) (average age: 22.0 ± 1.0 months old). The percentage of crude protein, panel tenderness score, polyunsaturated fatty acid (PUFA) and saturated fatty acid (SFA) content, the PUFA/SFA ratio and the hypocholesterolemic fatty acid (DFA)/hypercholesterolemic fatty acid (OFA) ratio of the bull carcasses decreased significantly with increasing slaughter age. By contrast, the OFA content of the carcasses significantly increased (p < 0.05) with increasing slaughter age. Advanced slaughter age resulted in lower panel tenderness scores. Additionally, the meat of the bulls in the OG was considered to be less healthy because of the less desirable fatty acid composition and nutritional indices, such as the PUFA/SFA and hypocholesterolemic/hypercholesterolemic ratios, compared to the meat from the bulls in the YG. Furthermore, the intramuscular fat and internal fat contained high percentages of PUFA and SFA and high PUFA/SFA and hypocholesterolemic/hypercholesterolemic ratios. Interestingly, the percentage of OFA content in the internal and intramuscular fat tissues decreased with increasing slaughter age. In conclusion, this study provided evidence that slaughter age and muscle and fat type are essential sources of variations in the textural characteristics, sensory panel attributes and fatty acid profile of meat from Holstein Friesian bulls.