The effects of substituting high moisture shelled corn (HMSC) for flaked corn (FC) on digestibility, nitrogen balance, production performance, and blood constituents of lactating dairy cows were investigated. A crossover trial using six lactating cows was conducted. Cows were fed ad libitum mixed rations consisting of grass silage, concentrate mixture, soybean meal, and FC or HMSC. The digestibility of crude protein was higher and that of starch tended to be higher for cows fed rations with HMSC than with FC. Although there was no difference between diets regarding the nitrogen intake, the fecal nitrogen excretion was lower and the retention of nitrogen was higher for cows fed rations with HMSC than with FC. No significant effects of the substitution were observed on the intake, lactation performance, and blood constituents. These results show that substituting HMSC for FC had no adverse effects on the production performance and blood constituents, but improved the digestibility and nitrogen utilization of dairy cows. Thus, HMSC can be used as a domestic concentrate feed for dairy cows in Japan.
Goats are the most suitable domestic animal to improve the botanical composition of abandoned fields owing to their foraging ability. The objective of the present study was to evaluate appropriate stocking rate of goats to improve the botanical composition of an abandoned field and maintain the nutritional status of goats in a favorable condition. An abandoned field was divided into two paddocks (0.5 and 0.3ha) with 7 (14 animals/ha) and 9 goats (30 animals/ha), respectively. They were stocked for 149 and 180 days during the first and second years of the study, respectively. Regardless of the stocking rate, herbage mass was controlled under 2t DM/ha after the start of grazing. Coverage of grass species increased gradually throughout the study period. Herbage intake and digestibility were not different between the two stocks. The goats fulfilled their nutritional requirements and maintained their body weight throughout the study period, except for once just after the start of grazing in the first year. The results suggest that goat grazing can fulfill the nutritional requirement of goats without any supplementary feeds, and also increases the coverage of grass within the range of stocking rate (14-30 animals/ha) in an abandoned field.
Interest in breeding timothy with improved plant competition including allelopathy is growing because of the serious invasion of quackgrass (Agropyron repens (L.) Beauv.) and reed canarygrass (Phalaris arundinacea L.) to the timothy-based grasslands in Hokkaido, Japan. This study investigated the varietal differences on allelopathy between the weeds and twelve timothy varieties. The percentage against the control of timothy root or shoot length showed significant varietal differences on resistance in germination test with weed water extract, plant-box method and agar-based method with the weeds. The potential allelopathic activity against weed root length also showed significant varietal differences in agar-based method with reed canarygrass. Yet, most of correlations among the methods were weak or almost absent in them on resistance. This may be attributable to the difference of function effects of allelochemicals, and suggests that comprehensive evaluation based on some tests should be desirable for evaluating the resistance. The relative ranking of varieties based on the percentage against the control showed some accordance in the results of between plant-box method or agar-based method and the early growth in the field test. These results suggest that selection focused on allelopathy may provide useful breeding improvement of timothy competitive ability.
To obtain one of the physioecological characteristics of the vulnerable plant species Pulsatilla cernua, we determined the base temperature and thermal constant of the germination of this species. We examined the germination time courses at five constant temperatures (10, 15, 20, 25, and 30°C) and used them for the nonlinear fitting of an exponential distribution with a lag phase. The distribution showed excellent goodness of fit to the observed germination time course at any temperature. We linearly regressed germination rate, which is a reciprocal of the duration for 50% germination of P. cernua seeds, against temperature to calculate the base temperature and thermal constant of seed germination. The linear regression showed excellent goodness of fit. The calculated values were 6.57°Cfor the base temperature and 142 degree days for the thermal constant. Using the base temperature, the thermal constant, and the daily air temperatures at the study site, we can predict that the seedling emergence of P. cernua will occur in the summer season.