Frequently, several herds of cattle that have been raised separately, on different farms or paddocks, are combined into a single herd and released to pasture. Often, herds that have been raised separately behave independently for several months afterwards. Mutually unfamiliar individuals from different farms do not interact much with each other. This study analyzed how the distances between grazing cows were determined in an 88×6-m pasture when two independent herds of four cows each, from different farms, were released to graze together. Collectively, the eight cows are referred to as the entire herd. The coordinates of each cow were recorded every 5 min. The distance between two given cows was determined using the following six effects, in order of priority : (1) behavior common to all the individuals in the entire herd (referred to as the entire herd length effect), (2) behavior common to all the individuals in each original herd (sub-herd length effect), (3) repulsive and attractive forces operating between two given individuals (direct effect), (4) the effects of a third cow (half-indirect effect), (5) the effects of unconnected pairs (indirect effect), and (6) any residual effect that is not explained by the previous five effects (random movement effect). Within each of the two original herds, the sub-herd length, and the direct and random movement effects made large contributions, while the entire herd length and indirect effects made small contributions ; the half-indirect effect was intermediate in determining the distances between individuals. Conversely, between the two original herds, the entire herd length made an overwhelmingly large contribution, and the other effects made small contributions in determining the distances between individuals.

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The effects of leader-follower grazing on intensively managed meadow fescue and perennial ryegrass pastures for dairy cattle were evaluated. A 1.6ha pasture was divided into 23 paddocks (each paddock being 7 a) and 4 lactating dairy cows were grazed on each paddock for 9 hours every day using the one-day grazing system. As followers, 2 heifers were grazed on each paddock, except for 3 control paddocks, for 24 hours starting immediately after the end of the cow (leader) grazing. Surplus grass in each paddock was harvested once a year. No significant differences in herbage yield and in nutritive value of herbage subjected to leader-follower grazing were found. The leader-follower grazing improved the efficiency of pasture utilization and did not affect the herbage intake of cows which was regulated by herbage allowance. Daily body weight gain of heifers (followers) was 0.87-1.02kg.

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This experiment was carried out to determine physicochemical characteristics of 24 feedstuffs including hay, grains, oilseed meals, bran and food processing by-products. The buffering capacity (BC) was also measured by titrations of acid or base added to 0.5g dry matter (DM) suspended in 50ml distilled deionized water until the pH decreased to 4 or increased to 9, respectively. Physicochemical parameters varied greatly between feedstuffs. Water holding capacity (WHC ; ml/g) ranged from 3.28 (barley) to 16.37 (red cabbage residue), bulk density (BD ; g/ml) ranged from 0.113 (red cabbage residue) to 0.752 (soybean meal), and osmotic pressure (OP ; mOsm /kg・H_2O) ranged from 24.1(safflower meal) to 164.8 (soy sauce cake). There were significant relationships between BD and both neutral detergent fiber content (DM%) and WHC, and between OP and both DM solubility (%) and ash solubility (%). Slopes of the titration curves differed for feedstuff's. Grains and brans had a low acid buffering capacity than hay and oil seed meals, while grains and food processing by-products(CP<15%) had a low base buffering capacity than brans. It is suggested that these physicochemical methods can give new and useful information about feed characteristics for ruminants.

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In many temperate grasses, the late heading cultivars/strains show better persistence than the early heading ones under grazing condition, but the former is disadvantage for seed production because of its few number of heads. It is important to identify the factors influencing the increase of head number. Recently, meadow fescue (Festuca pratensis Hud.) has been paid attention as a promising grazing species in the eastern Hokkaido because of its better regrowth compared to timothy. To clarify the effect of major environmental factors a comparison between extremely late heading strain 'Hokkai 9' and early heading cultivar 'Tomosakae' was carried out to evaluate heading characters at juvenile, primary (by low temperature) and secondary (by long photoperiod) inductive stage. As results, 'Hokkai 9' had juvenile stage at fall season condition (low temperature and short day-length), but 'Tomosakae' had no, or a very short, juvenile stage at same condition. Primary inductive duration whose 'Hokkai 9' was for 21 weeks at 6℃ with 8h photoperiod was longer three weeks than that of 'Tomosakae'. Though 'Hokkai 9' was suppressed for heading at 24/19℃ with 16h photoperiod at secondary induced, 'Tomosakae' continued heading at same condition. 24h photoperiod allowed to promote earliness of heading in both accessions, but therewas a difference for days between them. 'Hokkai 9' bred from Finish cultivar 'Tammisto' appears to be not adapted for heading characters at the middle latitude area such as Hokkaido, with shorter day length and higher temperature. Late cultivars / strains such as 'Hokkai 9' are essential for seed production to require enough duration of vernalization (6℃, 21 months) and condition of low temperature (15℃) with long-day length (above 14 hours-day length) at the second inductive stage.

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The intra-cultivar variation of regrowth after summer (RAS) of the first harvest year, the selection effectiveness, and the effect of selection on dry matter yield after summer was surveyed for festulolium cultivars Evergreen, Tandem and Paulita grown in cold climates. Intra-cultivar variation in the RAS in Evergreen had a rectangular distribution : a low frequency of awned individuals showed poor regrowth and a high frequency of awnless individuals showed better regrowth. The mean RAS values for Tandem and Paulita differed, but both were similar in that they showed smaller variation than Evergreen. For both Tandem and Paulita, most individuals had awned glumes and this differed from Evergreen, which was predominated by awnless individuals. In all cultivars, the groups that showed poor RAS were relatively more susceptible to crown rust. Genetic gains, which were estimated using two prgenies from each polycross of Evergreen clones and of Tandemand Paulita clones revealed significant selection effectiveness (Evergreen, p<0.01 ; Tandem and Paulita, p<0.01 as tentative value). Yield trials using progeny lines showed that the over-summer dry matter yield of the progenies was significantly higher than that of the parent cultivars (Evergreen and Tandem) at the 1% significance level. Given this result, the selection effectiveness of RAS was shown to also affect yield.

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