The present study was conducted to develop effective techniques for preventing Sika deer (Cervus nippon) invasion on the meadow. We investigated the behavioural response of the domesticated deer to electric fences (no electricity), sensitivity of parts of its body surface to electrical (aversive) stimulation, and the effect of electric fences (electricity) on wild animals' invasion on the meadow. (1) The 7 deer included in this study were very cautious against electric wires (no electricity) fixed at heights of 0-30 cm (stage 1), 30-60cm (stage 2), 60-100cm (stage 3), and 100-140 cm (stage 4) and to those at a height of 140 cm. One of the 7 deer touched the wires 23 times a day (1100 - 1800 h) with his lips, and eventually, passed through the 30 - 60 cm wires. This exploratory behaviour was observed more frequently in the following order: stage 2 (60 cm), stage 1 (30 cm), and stage 3 (100 cm) high wires. However, no exploratory behaviour was observed in stage 4 (140 cm) wires. (2) The electric resistance of the lips of the deer was evaluated to be 30, 000 Ω, which was extremely lower than those of other parts of the body surface, such as the forehead, back, belly, and right foreleg (a six-to three-thousandth) . Thus, it is suggested that lips having the lowest electric resistance were most sensitive to the aversive stimulation. (3) The stage 4 and 140 cm electric wires (voltage and pulse interval, approximately 4, 000 V and 1 s, respectively) set around the meadow were more effective in preventing the sika deer invasion than the 175 cm fence composed of synthetic fiber and wire nets.
These findings indicate that electric fences with high-tension current are effective in preventing the sika deer invasion on the meadow in livestock farm.

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The 24-bp insertion of the promoter region of prolactin gene was studied for 53 Silkie fowls, 19 Japanese native chickens and 6 commercial chickens. Forty-six Silkie fowls have genotype Del/Del, 7 Silkie fowls have genotype In/Del, however no Silkie fowls have genotype In/In. On the other hand, 11, 8 and 6 birds of other chickens showed genotypes Del/Del, In/Del and In/In, respectively. The chi-squared test using 2x3 table showed the significant difference (P<0.01) of the genotype frequencies between Silkie fowls and other chickens. These results show the significant difference of the genotype frequencies for the 24-bp insertion of the promoter region of prolactin gene between Silkie fowls and other chickens.

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To evaluate the meat production and quality of Japanese Black cattle fattened with only self-sufficient herbage mainly grazing, three cattle at 8 months of age were grazed for about 38 months. The herds were grazed rotationally on sown pastures of Italian ryegrass (Lolium multiflorum Lam.) and native pastures dominated by Chinese fountain grass (Pennisetum alopecuroides (L) . Sprenge) . When the available herbage mass of the pastures was insufficient, silage was fed to the cattle on the grazed pasture.
At the end of the fattening period, average weight of the cattle was 450.7 ± 25.4kg and average daily gain was 0.27 ± 0.02kg/day in the fattening period. All the carcasses were graded as C-1 (lowest grade) according to the Japanese Grading Standards. The meat from the carcasses had less fat (14.2 ± 3.5%) and energy (2.12 ± 0.24kcal/g), and had higher conjugated linoleic acid (CLA) content (4.8-9.0mg/g fat) than the meat produced by fattening beef cattle under conventional fattening system as presented in Standard Tables of Food Composition in Japan (2008) . In sensory evaluation, almost of palatability attributes (smell, juiciness and flavor) of the grass-fed beef were lower than that of Japanese Black beef on the market.
In conclusion, our results show that grass-fed fattening cattle can reach a final body weight of about 450 kg in a period of 38 months for fattening and produce meat rich in CIA as one of the bioactive substances, though they show slower growth rate and a lower sensory evaluation in regard to their meat than that of conventional fattening beef cattle.

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[in Japanese]

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To examine whether it's possible to produce safe and healthy meat type chicken without adding antibiotics to diets, we conducted a feeding trial. A shed used in the trial was completely disinfected. Four hundred birds, ‘Amakusa Daioh’ developed in Kumamoto prefecture were assigned to a 2 × 2 factorial design with sex, with or without antibiotics. Growth performances (live ability, body weight, feed intake, and feed conversion ratio) did not differ among the groups. The weights of muscles, breast, thigh and sasami, were not different among the groups. Further, the weights of liver, gizzard and heart did not differ among the groups.
These results indicate the possibility to raise meat type chicken with feeding diet without antibiotics when sheds are completely disinfected.

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In this study, 3, 349 Berkshire sows were examined in order to clarify the effects of genetic and environmental factors on their gestation length (GL) and litter size as the reproductive traits. The indexes of litter size were divided into the total parishioners (TP) and the number of the survival (SN) or the death parishioners (DPN), the mummies (MN) and those ratios (SNP, DPNP and MNP) for the total parishioners and the number of the weaning piglet (WN) as analysis objects. As a result of least squares analysis of variance with use of random effects of dam, the effect of dam was significant (P<0.01) for all traits, and heritability estimates from this study were 0.24 (TP), 0.21 (SN), 0.11 (SNP), 0.11 (DPN), 0.09 (DPNP), 0.06 (MN), 0.05 (MNP), 0.21 (WN) and 0.38 (GL) . These estimates indicated that the dam's genetic contribution to TP, SN and GL was higher than the other traits. The heritability for these traits was encouraging for within breed selection. The genetic correlation coefficient between TP and SN showed 0.93, and it was thought that the selection by TP brought a good result to SN. In addition, as for the effect of the parity was significant (P<0.01) for all traits and it was thought that the parturition was desirable as for five to six for an in-service term. From these results, it was suggested that the genetic improvements of the reproductive traits was one of the important subjects while considering their parity for the Berkshire sows which was not focused very much till now.

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In order to clarify the effects of the vitamin C (V.C) supplementation and supplementary diets on growing of carcass traits of Japanese Black steers by using ultrasound, vitamin A (V.A) and V.C in blood plasma were analyzed during fattening period and carcass traits and intramuscular fatty acid composition of M. longissimus thoracis were determined after slaughter. The experimental steers were divided into three groups as follows; control group of normal feed (Control group), treatment groups were fed V.C (30g/day) group (VC group) and V.C with soybean flour group (VC+SB group) added to the normal feed. The feed including V.C supplement was fed during 16.1 to 24.5 months of age, and all animals were slaughtered at 29 months of age. The body weight gain of treatment groups were larger than those of Control group during the fattening period, and the V.A concentration in plasma of treatment groups were lower than that of Control group during V.C added period. The relative increase of cross sectional area of M. longissimus thoracis (uMLTA) and Beef Marbling Standard (uBMS) by ultrasound of treatment groups was better than those in Control group. Especially, the relative increase of uBMS in VC group was higher than VC+SB group. The effect of V.C added to the feed was significant (P<0.05) for BMS (cBMS) judged after slaughter and α -linolenic acid (C18: 3) in M. longissimus thoracic. The cBMS in Control, VC and VC+SB groups were 5.8, 6.8 and 7.4, respectively, and α -linolenic acid were 0.14, 0.15 and 0.20 %, respectively. It was concluded that the growth of body weight, uMLTA and uBMS were increased by V.C supplementation to the feed.

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