Genes associated with fat metabolism have the potential to influence beef traits including fat deposition and fatty acid composition. Diacylglycerol O-acyltransferase 1 (DGAT1) encodes the enzyme acyl-CoA diacylglycerol-acyltransferase that plays a fundamental role in the metabolism of cellular diacylglycerol in physiological processes and catalyzes the final step in the synthesis of triglyceride. In this study, we investigated polymorphisms in full length coding sequence of DGAT1 and its association with the beef carcass traits. Sequence comparison of eight animals including four Japanese Black and four Holstein cattle revealed a nonsynonymous substitution, K232A in DGAT1. We investigated association between the genotype and carcass traits in two Japanese Black cattle populations (N = 438, 245). The effect of genotype was observed on subcutaneous fat thickness by analysis of variance (P < 0.05). Animals with DGAT1 K/K type indicated 0.29 point lower value in subcutaneous fat thickness than that with A/A type (P < 0.05). This result indicated that the polymorphism of DGAT1 K232A could be one of responsible genetic factors for subcutaneous fat thickness in Japanese Black cattle. This finding has important implication for production of high grade meat in beef cattle.

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In this study, we surveyed 290 commercial cow-calf operations in Japan for manganese, iron, cobalt, copper, zinc and molybdenum concentrations in prepartum diet for Japanese Black beef cows. All feed ingredients including roughage, concentrate, commercial compound feed, supplements and salt blocks were collected. Concentrations of the trace elements were measured by ICP mass spectrometry. Then we estimated concentration of each trace element in final diet by calculation from trace element concentration of each ingredient and its daily supply based on the questionnaire to feeders. Almost all the farms gave diet meeting the recommended value of manganese, iron, and cobalt (Japanese Feeding Standard for Beef Cattle 2008). The farms which gave diet with less copper or zinc concentration than the recommended value were 53.4% and 14.1%, respectively. Such diets with low copper or zinc were found more frequently in Hokkaido than in Tohoku and Kyushu-Okinawa areas. Diets with iron concentration above the maximum tolerant level (1,000 mg/kg DM, Japanese Feeding Standard for Beef Cattle 2008) were found in 4.1% of farms. Average calving interval in each farm was obtained from 242 farms. Calving interval was shorter in Hokkaido compared with Tohoku and Kyushu-Okinawa areas. In Kyushu-Okinawa area, shorter calving interval was associated with higher manganese, iron or copper concentration in the diet. In Hokkaido and Tohoku areas, calving interval was not correlated with any element. In summary, copper deficient diet for prepartum beef cow is still found frequently among cow-calf operations in Japan, and shorter calving interval was associated with high manganese, iron or copper in prepartum diet for beef cows in Kyushu-Okinawa area.

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SHIKORI (muscle inflammation) is considered to be a defect based on Japanese Beef Carcass Grading Standards, and results in economic loss, because meat containing SHIKORI will not be accepted or not well received by consumers. The cause of SHIKORI is currently unknown and has yet to be clarified. The objective of this study is to determine the frequency of SHIKORI occurring on beef carcasses in Japan. Specifically, carcasses were examined at 2 processing time points (carcass grading and cutting) of 493 fattening Holstein steers shipped from a farm with high SHIKORI occurrence. The trapezius muscle portion of the carcass was thoroughly examined for SHIKORI in the neck (Lean cubing), Chuck (Chuck roll), and Loin regions. In addition, the following processed cut regions were examined : Lean cubing, Chuck roll, Loin, Fillet, Brisket, Short plate, Top-round, Knuckle, D Rump, Gooseneck round and Shank. SHIKORI were assessed by the following parameters : SHIKORI occurrence rate (%) based on individual (right, left, or both) and regional localization. The regional occurrence rate were highest in the Loin (P < 0.01). When examining right versus left side carcass, there were no significant difference between left side and right side in SHIKORI occurrence rate at any cut regions. Comparing single versus dual side SHIKORI occurrence rates, single side rates were significantly higher for Chuck roll, Loin, D Rump and Gooseneck round regions (P < 0.05). In addition, SHIKORI occurrence rate of trapezius muscle at the Neck (Lean cubing), Chuck (Chuck roll), and Loin region were higher as compared to other muscle. All steers which had SHIKORI occurrence in the trapezius muscle were confirmed that the location always included the Loin cut. Therefore, these results indicate that ; 1) SHIKORI occurs by the cut region including the outer muscle like Loin in many cases ; 2) SHIKORI demonstrates no bilaterally symmetry, with differing single side—dual side occurrence rates ; and 3) SHIKORI in trapezius muscle is continuously spanning in this muscle, and more prevalent in the rear region of this muscle.

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The fluctuations of skatole and indole concentrations, which affect consumers' preferences of pork meat, were examined in 128 porcine fats and the sensitivity of some Japanese panelists to skatole was evaluated. Skatole concentrations in castrated and female pig back fats obtained from commercial markets were found to be in a range of 0.00 to 0.20 μg/g. In spite of such a considerable variation, the median skatole concentration was 0.02 μg/g, and most of the fats investigated contained low skatole. The median indole concentration was also low, 0.01 μg/g, and most of the fats investigated showed low indole concentration. The skatole concentration in back fats was not influenced by sex (castrated or female). There were strong positive correlations among the skatole concentrations of subcutaneous fats from different positions and between the skatole concentrations in back fats and intermuscular fats. The sensory evaluation suggested fat containing 0.10 μg/g or higher skatole could have a negative effect on pork meat quality.

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The present study examined the effect of stroking pregnant heifers on the kicking behavior and physiological response of primiparous cows at milking. Three experimental groups were designed : udder group (the experimenter stroked the udder of pregnant heifers, 10 cows), neck group (the experimenter stroked the neck of pregnant heifers, 9 cows), control group (the experimenter stood by the side of pregnant heifers, 9 cows). Treatments were conducted once a week from 30 to 28 weeks before calving to just before calving. Heifers were stroked for 10 minutes each time. Within 1 day of calving, within 1 day after being transferred from the calving pen to the milking herd, 30, 60, and 90 days after calving, the number of kicking events were counted, the heart rate increase (HR : 5 seconds interval, times/min) at milking was recorded, and the flight distance (FD) was measured for each cow. The number of kicking events per cow within 1 day of calving, 30, 60, and 90 days after calving were significantly lower for the udder group than the control group (respectively, P < 0.05). Until 30 days after calving, the number of kicking events per cow for the neck group was similar to those of the control group, after 60 days post calving, those for the neck group decreased and equaled the lowest number of kicking events for the udder group. HR increments at milking for the udder group were generally lower than those of the other 2 groups. The plasma concentration of cortisol (ng/mL) of all three groups increased after milking within 1 day of calving and after being transferred from the calving pen to the milking herd compared to those before milking, however, the effect of stroking was not clear. The FD of the two treatment groups was shorter than at the time they were separated into groups. The tendency of FD for the neck group was more significant. In conclusion, regular stroking of the udder after a heifer became pregnant to 2 weeks before expected calving, lowered the stress responses and the amount of kicking at milking for primiparous cows. Stroking the neck improved the relationship between the human and cow, and the decrease of the number of kicking events at milking for the neck group was slower than those for udder group and became the same as the udder group at 60days after calving.

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A thermophilic bacterium, Bacillus sp. TAT105, was reported to have efficient reduction of ammonia. To estimate the effect of adding Bacillus sp. TAT105 on ammonia emission during the composting process of swine manure, laboratory scale composting was done, and counted the numbers of thermophilic ammonium-tolerant bacterium. Swine manure was mixed with fresh dung and urine collected from sows, furthermore mixed perlite as bulking agent. The 5 kg manure was mixed with 100 mL culture adding Bacillus sp. TAT105, whereas the 5 kg manure was mixed with 100 mL TAT105-not-added culture. Each mixture was placed into a composting apparatus and kept continuous aeration. Tenfold of thermophilic ammonium-tolerant bacterium were observed in manure by adding Bacillus sp. TAT105 in comparison to control. Nitrogen emitted from manure adding TAT105 during composting test was decreased about 60% in comparison to control. Maximum ammonia emitted from pile of swine manure mixed rice hull adding Bacillus sp. TAT105 in 1 m³ piled scale decreased about 40% in comparison to control. Therefore, Bacillus sp. TAT105 was conceded as deodolizer of ammonia emitted during composting of swine manure.

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