To study the effect of social order on selection for two kinds of oats hay with similar proximate composition by ewes, 4 ewes were used for determination of dry-matter intake and selection behavior for oats hay. Four ewes (mean live weight; 47.7±1.8 kg) raised in the same flock were determined their social order by the feed scrambling method and were individually numbered by their order. The basal diet for 2 periods was composed either of 2 kinds of oats hay (A, B) with formula feed at the ratio of 7 : 3 on an as is basis. Hay selection trials with 20-min. period were carried out for 4 consecutive days by offering oats hay A and B at the same time immediately before morning feeding of the basal diet. Dry-matter intake and selection behavior were recorded by the use of video recorder for 20 min. of each trial. Proximate composition of 2 kinds of oats hay was about the same in crude protein, neutral detergent fiber and acid detergent lignin. The bulk volume was also the same in both hay. The kind of hay significantly affected on dry-matter intake of hay by all ewes, that is, intake of hay A was greater than B. The time spent for eating was significantly affected by the kind of hay for ewes of social ranking up to the third order. The ewe of 4^th order, however, showed statistical significance at only 10% level. The ewe of No. 1 ranking showed a greater dry-matter intake, time spent for eating and the length of eating bout for oats hay A. The time spent for eating and the length of eating bout for the No. 4 ewe, however, were significantly affected by the position of trough. Thus, the ewe of 4^th order selected the trough positioned far from the entrance of a pen for a longer time, although intake of hay A was significantly higher than B.
The present study revealed that ewes with the social ranking of both the highest and the lowest order were strongly affected by the dominance order for the selection behavior when 2 kinds of oats hay were selected by ewes in the same flock.

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The subjects of this study were one year old ram lambs under grazing. The duration and the time intervals of vocalization among them, features of their behavioral patterns and after vocalization and the subjects of vocalization were studied based on their behavior to obtain fundamental knowledge on their communication.
Their behavioral patterns at the time of vocalizations were divided into seven patterns by counting one type of relation between an individual ram lambs or sub-group and the subject of vocalization as one completed behavior. Approx 40% of them seem to be vocalizations and behaviors asking for feed, approx 40% for unity by individual ram lambs or herd, and the remaining 20% being of self-completion.
The average total number of vocalizations was 18.9 times/hour in pasture II and 25.5 times/hour in pasture II. When these figures are converted to a number of average vocalizations per individual ram lamb, 3.4 times/one ram lamb in the pasture I, 3.2 times/one ram lamb in the pasture There were 24 cases where one individual ram lamb vocalized two times or more successively. The average number of vocalizations was 5.2 times/one ram lamb, the duration ranges were of 0.88-10.34 s (the pasture I) and 0.69±0.26 s (the pasture II), the time intervals were 7.44±6.28s (the pasture I) and 6.5±3.89 s (the pasture II). This number includes one case of the pasture II where one individual ram lamb vocalized 20 times in succession. These vocalizations were made while the ram lamb was moving. The average duration of these vocalizations were 0.56 s and the average time interval 5.13 s, both tending to be shorter than those of other individuals.
The minimum duration of vocalization in the pasture I was 0.25 s which was made by an individual of pattern VI when responding to another individual, and that in the pasture II was 0.2 s which was made by the individual of pattern I that vocalized successively. The maximum value in the pasture I was 1.99 s which was made by one individual of pattern III that vocalized successively, and that in the pasture II was 1.57 s which was made by a responding of pattern VI individual. As for the duration of vocalizations made by one individual successively, the maximum value in the pasture I was 1.37 s of pattern III, that in the pasture II was 1.24s of pattern V, and the minimum value in the pasture I was 0.3 s of pattern I, that in the pasture II was 0.2 s of pattern I. There were no significant differences in the average values between the two pastures, the values being concentrated in the range from 0.5 to 1 s. The medians of the vocalization duration in the pasture 1 were significantly larger (P < 0.01), with the values being concentrated around 0.9 s.
As for the time interval from a vocalization of one individual to a vocalization of another individual, 4 to 10 s accounted for 50% of the total in the pasture I and 1 to 5 s accounted for 53% of the total in the pasture II. In the pasture I, 12.1% of individuals responded within 0.5 s, while 2.1% in the pasture II. The behavior of the individuals responded within 0.5 s in both the pasture I and II was either standing or moving. The time interval of 20 s or longer accounted for 3.3% of pattern III or IV in the pasture I and 7.3% of pattern I in the pasture II. The behavior of the responded individuals in the pasture I was standing, while that in the pasture II was moving. The time interval between successive vocalizations made by one individual was concentrated in the range from 4 to 7 s in both the pasture I and II.

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The palatability of the lamb meat of domestic production and importation (Hokkaido and New Zealand) were evaluated. The panel consisted of 28 girl students, aged 18.9. The meats (loin) were evaluated, after dipping into the boiling water for 10-15 seconds (traditional cooking in Japan, called “Shabushabu”). The sensory evaluation was performed according to the method of Scheffe. The checking point were color, odor, tenderness, flavor and total point evaluations.
As results, there were significant difference in the domestic and New Zealand lamb, and the evaluation that the domestic lamb is higher was gotten about the color and total point evaluation. As for item of the odor, the tenderness, the flavor, among both, there was no significant difference. However, as for these point distribution, by the point on the side of +, the higher tendency had the domestic lamb compared with the New Zealand lamb.

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In order to test the effect of physical signal by extension of rumen or metabolic signal from fermentation of feed, two rumen-cannulated sheep were offered grass hay ad libitum once daily. Sheep was given the distention of the rumen by three tennis balls (450 ml) or infusion of the solution of volatile fatty acids (2.2 mol/d acetate and 0.6 mol/d propionate) in the rumen. The treatments were composed of control (C), distention by the tennis balls (B), infusion of volatile fatty acids (V) and B + V. Dry matter intake of C, B, V and B + V were 1333.7 g/d, 1083.7 g/d, 1363.8 g/d and 864.3 g/d, respectively. Meal appeared frequently and the intake increased immediately after feeding in C, whereas the intake in other three treatments had a tendency to increase as time passed from feeding. There was a significant positive correlation between meal size (MS) and preceding meal interval (PMI) in C and V during the day. MS of B+ V was positively correlated with following meal interval (FMI) by day. The ratio of MS/PMI and MS/FMI of C was higher than those of B, V or B V. Voluntary intake was influenced by the change of pattern of meal appearance be caused by distention of rumen or metabolic signal. In addition, this tendency was more noticeable when the treatments were combined simultaneously (B+ V) rather than individually (B or V). The results of this experiment suggested that voluntary intake by ruminants was controlled by the additive effect of physical signal from the rumen wall and metabolic signal.

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