No abstract

The changes in i.m. fat deposition in the principal muscles [M. semitendinosus, M. semimembranosus, M. psoas major, M. latissimus dorsi, LM (7th to 8th and 10th to 11th thoracic vertebrae), and M. supraspinatus] from 24 to 30 mo of age were investigated using identical twins of Japanese Black steers. Four sets of identical twins of Japanese Black steers were used in this study. Animals were fattened from 10 to 24 or 30 mo of age for each pair of identical twins. Body weights of twin steers slaughtered at 24 and at 30 mo of age were similar at 10 mo of age and thereafter up to 24 mo of age. The changes in serum concentration of vitamin A, glucose, total cholesterol, albumin, and total protein were similar in each pair of twins during the first fattening stage (10 to 24 mo). Fat contents of LM (7th to 8th thoracic vertebrae) at 24 and 30 mo of age were 37.0 and 42.4%, respectively (P < 0.05). Moreover, in the principal muscles, except M. semimembranosus and M. supraspinatus, fat content at 30 mo of age was greater than at 24 mo of age (P < 0.05). The proportional increase in fat content from 24 to 30 mo of age was greatest in M. semitendinosus (+58.7%) and least in M. supraspinatus (+6.1%). These results demonstrate that i.m. fat continues to increase after 24 mo of age, and the rates of i.m. fat deposition and the ages when i.m. fat is deposited are different for every muscle.

A genome-wide scan for QTL affecting economically important traits in beef production was performed using an F(2) resource family from a Japanese Black x Limousin cross, where 186 F(2) animals were measured for growth, carcass, and meat-quality traits. All family members were genotyped for 313 informative microsatellite markers that spanned 2,382 cM of bovine autosomes. The centromeric region of BTA2 contained significant QTL (i.e., exceeding the genome-wide 5% threshold) for 5 carcass grading traits [LM area, beef marbling standards (BMS) number, luster, quality grade, and firmness), 8 computer image analysis (CIA) traits [LM lean area, ratio of fat area (RFA) to LM area, LM area, RFA to musculus (M.) trapezius area, M. trapezius lean area, M. semispinalis lean area, RFA to M. semispinalis area, and RFA to M. semispinalis capitis area], and 5 meat quality traits (contents of CP, crude fat, moisture, C16:1, and C18:2 of LM). A significant QTL for withers height was detected at 80.3 cM on BTA5. We detected significant QTL for the C14:0 content in backfat and C14:0 and C14:1 content in intermuscular fat around the 62.3 to 71.0 cM region on BTA19 and for C14:0, C14:1, C18:1, and C16:0 content and ratio of total unsaturated fatty acid content to total SFA content in intramuscular fat at 2 different regions on BTA19 (41.1 cM for C14:1 and 62.3 cM for the other 4 traits). Overall, we identified 9 significant QTL regions controlling 27 traits with genome-wide significance of 5%; of these, 22 traits exceeded the 1% genome-wide threshold. Some of the QTL affecting meat quality traits detected in this study might be the same QTL as previously reported. The QTL we identified need to be validated in commercial Japanese Black cattle populations.

Regarding the fattening of younger cattle that the Ministry of Agriculture Forestry and Fisheries (MAFF) recommends in Japan, this study looked at vitamin A control in feed and blood and its effect on performance of production and carcass composition of Wagyu steers. Five sets from 10 Wagyu artificial identical twins were divided to into 2 groups, a restricted group (Test) and a supplied group (Control). The body weight at the finishing time of the Test was significantly lower than that of the Control (p<0.05). The daily gain from 13 to 21 months old, as the animals in the Test were fed the concentrated feed without Vitamin A, was significantly different (p<0.05) between the Test and the Control. The total daily gains for the Test and the Control for the fattening period were 0.82 kg/day and 0.93 kg/day, respectively, which showed a significant difference (p<0.01). Regarding the rib thickness, the Test was thinner than the Control. The Beef Marbling Scores of the Test and Control were 3.60 and 2.80, respectively. The muscle weight of the Test was significantly smaller than that of the Control (p<0.01). However, regarding the ratio to the carcass, the Test was significantly higher than the Control (p<0.05). For the fat weight, the Test was smaller by about 15 kg than the Control (p<0.01). Furthermore, for the fat ratio to the carcass, the Test was significantly lower than the Control (p<0.05). The bone weights of the two groups were approximately the same. Regarding the ratio of bone to carcass, the Test was higher than the Control (p<0.01). For the younger fattening method, the low level vitamin A in the serum had the effect that the muscle ratio to the carcass weight was greater and the fat was less, but the carcass and muscle weight were less.

in this paper, we report the image processing technique for computer-aided diagnosis of lung cancer screening system by CT (LSCT). LSCT is the newly developed mobile-type CT scanner for the mass screening of lung cancer by our project team. in this new LSCT system, one essential problem is the increase of image information to be diagnosed by a doctor to about 30 slices per patient from I X-ray film. To solve this difficult problem, we are trying to reduce the image information drastically to be displayed for the doctor by image processing techniques. We propose a new method named Variable New-Quoit filter for the automatic recognition of the pathological shadow candidates. Our computer aided diagnosis (CAD) system can satisfactoiily reduce the number of CT cross sections by this method, containing the abnormal shadow candidates.

No abstract

The effects of intramuscular fat on the sensory characteristics of M. longissimus dorsi in Japanese Black steers were investigated by a trained analytical panel (average 13.4 panelists). Five sets (10 head) of artificial identical twins were divided into 2 groups, high level of intramuscular fat group (HG) which utilized the fattening method of increasing intramuscular fat and low level of intramuscular fat group (LG) which did not use the above method. Regarding M. longissmus dorsi which was produced for use in the sensory evaluation, crude fat contents of HG and LG was 25.8% and 23.2% respectively (p<0.05). Warner-Bratzler shear force, water holding capacity, cooking loss and fatty acid composition of HG and LG were similar between the two groups. M. Longissimus dorsi taken from HG and LG were tested for their sensory characteristics by a trained panel. HG was given higher points for juiciness than LG (p<0.05). There were no significant differences for tenderness and flavor between the two groups. Overall acceptability which synthesized each of the sensory characteristics of HG and LG were 5.04 and 4.69 points respectively (p = 0.05). These results suggested that juiciness increased with the increase of intramuscular fat, and this raised the overall acceptability of M. longissimus dorsi.

COX-2 is an inducible cyclooxygenase (COX) that has been reported to be expressed in the macula densa and surrounding cortical thick ascending limb in normotensive rats. The present study assessed the contribution of COX-2 in three different rat models of hypertension, each characterized by a different activation of the renal renin-angiotensin system. Mean blood pressure (MBP) in the rat 2 kidney-1 clip (2K1C) model was significantly reduced with a COX-2 selective inhibitor, NS-398 (10 mg/kg, p.o., twice a day) (vehicle-administered rats (n = 8): 154 +/- 6 mmHg; NS-398-administered rats (n = 5): 128 +/- 10 mmHg). By contrast, a COX-1 selective inhibitor, mofezolac, did not lower MBP. Increased plasma renin activity (23 +/- 8 ng/kg/h (n = 6) vs. sham operation, 2.4 +/- 0.9 ng/kg/h (n = 4)) was markedly reduced to 6.8 +/- 2.7 ng/ml/h (n = 5) by NS-398, but not by mofezolac. The development of 1 kidney-1 clip (1K1C) hypertension was also inhibited by NS-398 (vehicle (n = 12): 133 +/- 1 mmHg; NS-398 (n = 7): 122 +/- 3 mmHg) accompanied by a reduction in plasma renin activity (3.0 +/- 0.3 ng/ml/h, n = 4) to 1.0 +/- 0.2 ng/ml/h (n = 5). The COX-2 inhibitor increased urinary excretions in the 1K1C model, but not in the 2K1C model. In a deoxycorticosterone acetate (DOCA)-salt model, plasma renin activity was markedly suppressed to less than 0.3 ng/ml/h. The COX-2 inhibitor caused no significant changes in MBP, plasma renin activity, or urinary excretion, suggesting that COX-2 made a lesser contribution in this model. Increased expression of COX-2 mRNA and protein was observed in the kidneys of 1K1C and 2K1C rats, but not in DOCA-salt rats. These results suggest that COX-2 plays a significant role in the development of 2K1C and 1K1C renovascular hypertension, in addition to making a substantial contribution to the diuretic effect in the 1K1C model.