The study was to investigate effect of day-time light illumination on the behavior of ewes. A total of 8 ewes given alfalfa hay with free access were divided into 2 groups of 4. Ewes in one group were treated with a daily 4-h light illumination of 5, 000 to 12, 000 lux for 14 days in late August. Ewes in treatment group were kept in a roofed paddock with those of control group except for treatment hours. After the treatment, ewes were housed in an individual crate for 30 days. During this period, the observation was carried out on the daily intake of dry matter and the behavior of eating and lying for 12 hours. Then, ewes were kept in a flock and had an access with a ram for 8 hours in daytime when their behavior was recorded with video recorder for mating. The mating was confirmed with marking crayon. Daily dry-matter intake was 29.9±2.7 g/kg of live weight for treatment group and 30.9±2.5g/kg of live weight for control group. The proportion of time spent for eating or lying occupied 30 to 35% or 45 to 50% of 12-h observation. There were no significant differences in dry-matter intake between treatment and control groups nor in eating and lying behaviors. Only one ewe in treatment group refused to mate with the ram. Results of mating observation did not clarify the effect of a daytime light illumination on reproductive behavior of ewes. Possible causes were discussed.

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The effects of creep feeding on the growth of body weight and the development of ruminoreticulum were investigated during 3 months of nursing period.
Eight Suffolk ewes and their lambs (two single born lambs and six twins) were used for this study. Three twins were fed creep feed from 2 weeks of age. The data for ram lambs only were used for this study.
Ewes and their lambs were kept in pen of 4-5 m² each. Ewes were fed at 8 : 30 and 17 : 00. Creep feed for lambs was given once a day in the adjoining pen. The residues of creep feed was measured at the next feeding. Body weight of ewes and lambs were measured once a week. After the weaning at 3 months of age, lambs were slaughtered, then the weight of ruminoreticulum, omasum and abomasum was measured, and the length of papillae was measured. Difference between means were tested for significance by two sample t-test.
The twin lambs fed creep feed showed satisfactory growth until weaning. However, the growth rate of the other lambs decreased after 7-8 weeks of age. The mean body weight at weaning and the daily gain from birth until weaning of the twin lambs fed creep feed were 1.48 times and 1.53 times bigger than the means of the other twins, respectively (P < 0.05). In the case of the single born lambs, those means were intermediate values between the means of the twin lambs fed creep feed and the other twins.
The mean weight of ruminoreticulum, omasum and abomasum of the twin lambs fed creep feed were 1.54 times, 1.60 times and 1.54 times bigger than the means of the other twins, respectively (P< 0.05). In the case of the single born lambs, those means were intermediate values between the means of the twin lambs fed creep feed and the other twins.
The ratio of the weight of ruminoreticulum to the body weight, the metabolic body size and the weight of abomasum at weaning did not show significant difference between the values of the twin lambs fed creep feed and the values of the other lambs. These results showed that ruminoreticulum, omasum and abomasum were developed simultaneously with the increase of body weight by creep feeding.
The twin lambs fed creep feed showed higher development of papillae than the other lambs (P< 0.05).

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To examine the association of apolipoprotein E (apo E) polymorphism with plasma lipid levels using 116 ewes of Corriedale, Suffolk and Cheviot sheep, plasma lipids such as total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides of different apoE phenotype groups consisting of more than five animals were determined by enzymatic assay. In the Corriedale sheep, significant differences in TC and LDL-C levels among four apoE phenotypes 1/4, 2/4, 4/4, and 4/7 were seen according to the one-way analysis of variance (P=0.003 for TC and P=0.008 for LDL-C). The order of both lipid levels in these phenotypes was as follows : 2/4>4/4>4/7>1/4. On the other hand, insignificant differences in each of four plasma lipid levels among four apo E phenotypes 4/4, 4/5, 4/7, and 5/7 were shown based on the analysis of variance in the Suffolk sheep. However, type1/4 or 4/4 animals had a tendency for higher levels of TC and LDL-C compared with type 4/5 or 5/7 animals. In the case of the Cheviot sheep, type1/4 animals tended to have a higher HDL-C level than type 4/4 animals, in addition to TC and LDL-C. These results therefore suggested that apo E polymorphism is associated weakly with plasma lipid levels such as TC or LDL-C.

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This study aims to compare the reproductive performance of seasonally anestrous ewes which were exposed to ram starting from 94 days after lambing; fed with 2 different level of TDN at early mating period; hormonally treated with PMSG and PGF_2α.
Forty-five Suffolk ewes weaned at 73 days after lambing were divided into following 4 groups namely :
Group H 0 - exposed to ram for 39 days; consumed 1.15 kg TDN/day
Group H 1- exposed to ram for 39 days; consumed 1.15 kg TDN/day; hormonally treated at 13 days after exposure to ram with PMSG (500 IU) and PGF_2α (15 mg)
Group M 0- exposed to ram for 30 days; consumed 0.89 kg TDN/day
Group M 1- exposed to ram for 39 days; consumed 0.89 kg TDN/day; hormonally treated at 13 days after exposure to ram with PMSG (500 IU) and PGF_2α (15 mg)
All groups of ewes were maintained on natural daylength or supplemented with 20-24 hours of artificial lighting during perinatal period. Fisher's exact probability test was adopted to detect statistical difference among groups.
The incidence of estrus and pregnancy rate was higher than 92% and 50% respectively in all groups, however, there was no significant difference among treatment groups. The daylength pattern during perinatal period had also no significant effect on the incidence of estrus and pregnancy rate. Intake of 1.15 kg of TDN/day improved the daily gains of ewes in group H 0 and H 1, however, failed to show significant effect on the incidence of estrus and pregnancy rate.
In conclusion, this study was able to demonstrate that exposure of ewes to ram without hormonal treatment successfully induced fertile estrus. Moreover, exposure to ram in combination with PMSG-PGF_2α treatment induced cyclic ovarian activity and synchrony of estrous time was achieved.

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Three rumen cannulated Japanese Corriedale crossbred (Suffolk × Corriedale) sheep (mean BW 35.1 kg) offered corn silage (CS) and chopped timothy hay (TH) ad libitum were used to examine the effect of forage properties (physical and chemical) on saliva secretion and rumination behavior. Eating and rumination behavior was monitored for each animal fitted with a muzzle which is equipped with a strain-gage unit for five consecutive days. Saliva secretion was estimated using a kinetics model based on the rumen fluid and water flux estimates across the rumen wall. Voluntary food intake and saliva secretion were significantly higher (P<0.05) in animals offered TH than CS. Total rumination time, number of rumination chews and number of regurgitated boli were markedly higher (P<0.05) due to TH feeding than CS. Chewing rate, chewing number/bolus and chewing time/bolus tended to be higher due to TH feeding than CS (P>0.05). Rumination index (min/100 g DMI) was significantly higher (P<0.05) due to TH feeding than for CS. It was elucidated that coarse forage feeding increased voluntary food intake, saliva secretion through mechanical stimulation of rumen fill compared with succulent fermented forage such as silage.

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The distinction of sheep herds by nomads between oter herds has been done by painting lacquer on the back and on the tail of the sheep. They confirm thier own herd by the cut of ear, and the cut of abdominal hair. Nomads have developed the skill of discriminating their own individual animals through their experience, and their own herd management skill to guard against mixing with other herds.

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