Food plant selection by the wild Japanese serow (Capricornis crispus) with reference to the traces eaten

Vegetation and plants eaten by the serow were investigated once a month from spring to autumn in two areas with different vegetative composition of deciduous broad‐leaved trees and forbs. Then we calculated Ivlev's electivity indices (EI) for some plant species and six plant groups: the deciduous broad‐leaved tree, the evergreen broad‐leaved tree, the conifer, the forb, the graminoid and the fern. In Area 1, the frequency of deciduous broad‐leaved trees and forbs was 78.2% and 1.1%, respectively. The proportion of deciduous broad‐leaved trees and forbs eaten was 65.9% and 33.1%, respectively. In Area 2, the frequency of deciduous broad‐leaved trees and forbs was 32.4% and 23.1%, respectively. The proportion of deciduous broad‐leaved trees and forbs eaten was 46.9% and 52.0%, respectively. In Area 1, the deciduous broad‐leaved tree was eaten in proportion to its frequency in the habitat (EI, 0.06–0.05) except in May (?0.32) and June (?0.11). The deciduous broad‐leaved tree was a little selected in Area 2 (0.02–0.46) except in June (?0.41) when serows selected some forb species. In Area 2, forbs were selected throughout the observational period (0.16–0.97), except during July (?0.05) when serows fed mainly on deciduous broad‐leaved trees (0.46).     

Initiatives and behavioral sequence of maternal behavior in Japanese Black and Japanese Shorthorn cattle (Bos taurus)

Maternal grooming (MG), nursing (NS) and mother‐infant behavior 5 min before (IB5) and immediately before (LIB) maternal behavior were observed in Japanese Black (JB) and Japanese Shorthorn (JS) cow‐calf pairs. During MG of the JB, the number of calf's IB5 was more than that of cows, but the duration of the MG positively correlated with the number of cow's IB5. During MG of the JS, the duration positively correlated with the number of calf's IB5. The number of the NS with calf's LIB and the number of calf's IB5 in the NS were more than those of cows in both breeds. The duration of the NS tended to correlate with the number of calf's IB5 in the JS. Main behavior sequence was observed like cow's approach, MG, calf's contact and NS, in this order, in both breeds. It is thought that the MG is released by cow's and calf's activities in both breeds and accelerated by the cow's activeness in the JB and by the calf's activeness in the JS, and that the NS is released and accelerated by the calf's activeness in JS.     

Effect of ground cover on splash and sheetwash erosion over a steep forested hillslope: A plot-scale study

The contributions and relationships of erosion by splash and overland flow over a steep slope in a Japanese beech forest in plots with different percentages of ground cover were examined. Three erosion plots (2 m wide × 5 m long) with average understory coverage of 1%, 45%, and 94% were installed. Sediment transported by rain splash and by overland flow was sampled separately. For the plots with sparse, moderate, and high understory coverage, the average proportions of splash soil to total soil erosion during the monitoring period were 16%, 32%, and 18%, respectively. A significant correlation between the amount of splash soil and precipitation was found in the plots with 1% and 45% understory coverage, whereas no statistical relationship was identified for the plot with high understory coverage. At the sparse ground cover plot showing the largest sediment movement, the contribution of splash transport decreased with increasing precipitation. The amount of sheetwash erosion was significantly correlated with the amount of splash soil under the condition of sparse ground cover. This relationship was more pronounced during high precipitation events and the rainy season. Splash contribution to the sediment transport was in the range of 0.8%–76.7%, 2.8%–81% and 2.1%–60.8% for plot with high, moderate and low ground cover, respectively. The sparse ground cover showed the largest variation of splash and sheetwash contribution in soil erosion. This variability was due to variation in ground cover and soil surface wetness condition which led to a variation of detachment and non-linear relationship of sheetwash splash.     

Physiological responses of young cross‐bred calves immediately after long‐haul road transportation and after one week of habituation

We investigated 10 suckling cross‐bred calves (Japanese Black (Wagyu) × Holstein) and collected data on the physiological stress responses of the young calves to long‐haul road transportation. All calves were male and 21–47 days of age. The calves were obtained at a livestock market and were transported from the market to the university in a commercial livestock vehicle. The total haul distance and time were 306.9 km and 7 h, respectively. The calves were deprived of food and water during transportation. Blood samples, electrocardiograms, and rectal temperatures were collected immediately after transportation and after one week of habituation at the university. Serum pH was significantly lower (P < 0.01), while serum triiodothyronine, aspartate aminotransferase, non‐esterified fatty acids (all P < 0.05), and heart rate (P < 0.01) were significantly higher immediately after transportation. The concentrations of blood lactic acid (P = 0.08) and serum alanine aminotransferase (P = 0.06) tended to be higher after transportation. These physiological responses suggest that the stress caused by long‐haul transportation causes significant effects on liver function in young calves.     

Long-term changes in the assemblage of demersal fishes and invertebrates in relation to environmental variations in Tokyo Bay, Japan

Abstract Long-term changes in the demersal assemblage, including both fishes and invertebrates, in Tokyo Bay, Japan, were examined between 1977 and 1995. A total of 255 species were collected, of which 113 were regarded as representative in terms of occurrence. Multivariate analyses of the representative species showed that fluctuations in the catch were related to three periods that reflected changes in relative abundance and species composition. In particular, mantis shrimp, Oratosquilla oratoria (de Haan), whipfin dragonet, Repomucenus valenciennei (Temminck & Schlegel), and marbled sole, Pleuronectes yokohamae Günther, showed high dominance in the mid-1980s. Discriminant analysis suggested that the demersal assemblage changed synchronously with environmental conditions. Causes of the temporal changes in the demersal assemblage in relation to variations in environmental factors are discussed.     

Individual difference in serum oxytocin concentrations of calves and the correlation with those in dams

We examined individual differences in serum oxytocin concentrations (OT) of calves, and assessed whether these differences were correlated with their dams’ milk and serum OT. Eight Holstein (H), nine Japanese Shorthorn (JS), and six Japanese Black (JB) calves were examined. Blood was collected three times during the first month in H calves, while their dams’ blood was collected three times prior to parturition. Milk was collected twice after parturition from H cows. Blood from JS and JB calves were collected at 1 and 4 months old, while of their dams only once before parturition. Serum OT in H calves at 7 days old was significantly correlated with that at 30 days. Serum OT of JS calves at 1 month old was significantly correlated to that at 4 months, while of JB calves was also positively correlated (r = 0.70). Serum OT of calves showed significant individual differences in each breed. Serum OT of calves was not correlated with the milk OT of dams, except for 3‐day‐old calves that fed on their dams’ milk. We concluded that although serum OT differed among individuals, this difference was stable within each individual and not affected by the serum OT of the dams.     

Effects of haul distance and stocking density on young suckling calves transported in Japan

We conducted applicability evaluation of recommendations of the European Union (EU) and the Royal Society for Prevention of Cruelty to Animals (RSPCA) for suckling calves. Nineteen calves (14 Holstein aged 11–26 days and five cross‐bred aged 13–45 days) were divided into six groups. Three groups were allocated into the stocking densities of 0.25, 0.35, 0.45 m²/head and were weekly transported 50, 100, 150 km in this order. Another three groups were allocated and transported in reverse order. Observation was conducted during and after transportation. Blood sampling was performed before and after transportation. The occurrences of lying and turning round on the truck were significantly associated with stocking density (P < 0.05), but not with haul distance. Scratching was observed only in one calf. Incidence of watery feces was not associated with both factors. There were significant effects of haul distance on the concentrations of plasma cortisol and noradrenaline, and serum aspartate aminotranserase (AST) and IgM (P < 0.05). These concentrations, except cortisol, were higher after transportation at 150 km compared to the pre‐transportation value (AST and IgM P < 0.05; noradrenaline P < 0.10). Results suggest that haul distances greater than 100 km should not be recommended even for suckling calves transported in Japan.     

Distribution of radioactive cesium and stable cesium in cattle kept on a highly contaminated area of Fukushima nuclear accident

Radioactivity inspection of slaughtered cattle is generally conducted using a portion of the neck muscle; however, there is limited information about the distribution of radioactive cesium in cattle. In this study, therefore, we measured not only radioactive cesium but also stable cesium in various tissues of 19 cattle that had been kept in the area highly contaminated by the Fukushima nuclear accident. Skeletal muscles showed approximately 1.5‐3.0 times higher concentration of radioactive cesium than internal organs. Radioactive cesium concentration in the tenderloin and top round was about 1.2 times as high as that in the neck muscle. The kidney showed the highest concentration of radioactive cesium among internal organs, whereas the liver was lowest. Radioactive cesium concentration in the blood was about 8% of that in the neck muscle. Characteristics of stable cesium distribution were almost the same as those of radioactive cesium. Correlation coefficient between radioactive cesium and stable cesium in tissues of individual cattle was 0.981 ± 0.012. When a suspicious level near 100 Bq/kg is detected in the neck of slaughtered cattle, re‐inspection should be conducted using a different region of muscle, for example top round, to prevent marketing of beef that violates the Food Sanitation Act.