Genetic effects on fatty acid composition of carcass fat of Japanese Black Wagyu steers.

Two hundred ninety-three Japanese Black Wagyu steers derived from 34 sires were used to investigate genetic effects on the fatty acid composition of carcass fat. All steers were fed identical diets for 365 d and slaughtered at similar ages. If the percentage of genetic contribution of sire A, B, or C was not lower than 25%, steers were classified into groups A, B, and C, respectively. Fatty acid compositions differed depending on deposit sites. Mean percentage of monounsaturated fatty acids (MUFA) tended to be higher in the outer parts than in the inner parts of the body. Percentage of MUFA in carcass fat was negatively correlated with withers height and BW and positively correlated with meat quality score and marbling score. Fatty acid compositions of the 34 sire groups varied, and mean percentages of MUFA in i.m. fat ranged from 47.71 to 54.77%. Steers in the C group grew larger than those in the A or B group. Mean percentages of MUFA for i.m. fat in the A, B, and C groups (52.83, 51.88, and 50.33%, respectively) differed (P < 0.05) from each other. Steers in the C group had higher (P < 0.05) percentages of saturated fatty acids than those in the A or B groups. Percentages of genetic contribution of sires B (P < 0.05) and C (P < 0.001) were negatively correlated with percentage of MUFA in i.m. fat. These results suggested that genetic factors affected fatty acid composition of carcass fat in Japanese Black Wagyu cattle and that some sires had potent genetic factors affecting this composition.

Modified sagittal split ramus osteotomy with a reciprocating saw and new retractors.

Modified sagittal split ramus osteotomy with new instruments and a reciprocating saw is reported. With this modification, the sagittal separation of the ramus is performed by the reciprocating saw with an original wide-blade buccal retractor and a new lingual retractor, instead of the traditional channeled retractor. The wide-blade retractor is inserted to the buccal aspect of the mandibular ramus, which ensures protection from instrumental injury to the adjacent soft tissues and vessels, and the new lingual retractor, instead of the channeled retractor, is inserted to the lingual aspect of the ramus. The osteotomy line follows that of Dal Pont's modification. Close attention must be paid to the direction of the saw blade. The separated bone plane should be located in the external cortical bone layer of the ramus, so as to avoid injury of the inferior alveolar neurovascular bundle. The osteotomy is completed with the smooth osteotomized interface, which facilitates positioning of the bone segments by the surgeon. The new instruments and the reciprocating saw may provide safe and rapid sagittal split ramus osteotomy.