Carrier rate of the c.235G>C mutation in the bovine isoleucyl-tRNA synthetase (IARS) gene of Japanese Black cows at Kagoshima prefecture, Japan,and analysis of the metabolic profiling and reproductive performance of heterozygous cows

Bovine isoleucyl-tRNA synthetase (IARS) disorder, a major cause of weak calf syndrome, is caused by a homozygous missense (c.235G>C) mutation in the bovine IARS gene of Japanese Black (JB) cattle, which was identified in 2013. However, the extent to which the carrier rate has changed at Kagoshima prefecture, Japan, and whether the carrier status is associated with any clinical or reproductive problems, have yet to be ascertained. In this study, using a real-time polymerase chain reaction-based genotyping assay, we determined the carrier rate in a regional JB cow population at Kagoshima prefecture. Comparative analyses were performed on the metabolic profile test (MPT) results and reproductive performance data obtained for heterozygous carrier and homozygous wild-type cows. In 2009 and 2018, DNA samples were collected from 130 and 462 clinically healthy JB cows, respectively, in Kagoshima prefecture. MPT results and reproductive performance data were evaluated for 62 cows, comprising four heterozygous carriers and 58 wild-type cows. Genotyping revealed that the carrier rate was 6.9% in 2009 and 1.5% in 2018, the difference of which was statistically significant (P<0.005). There were no statistically significant differences between the carrier and wild-type cows with respect to either MPT results or reproductive performance, indicating that the carrier cows have necessary IARS activity to maintain minimal health and reproductive potential.     

Effects of a high milk intake during the pre‐weaning period on nutrient metabolism and growth rate in Japanese Black cattle

This study aimed to determine the effects of feeding an increased volume of high‐fat milk during the early post‐natal life on metabolite concentrations in the blood, the expression of key genes regulating intermediary metabolism in the skeletal muscles, and the rate of growth of Japanese Black cattle. All calves were fed a high‐fat milk replacer (crude protein, 26%; crude fat, 25.5%; total dissolved nitrogen, 116%). Control calves (n = 4) were nursed with 500 g milk replacer until 3 months of age, whereas calves in the experimental group (n = 4) were nursed with 1800 g milk replacer until 3 months, and then the volume was gradually reduced until 5 months. Body weight was significantly higher in the experimental group than in the control group at 7 months. Plasma glucose concentrations were significantly lower in the experimental group. Expression of glucose‐transporter‐4 messenger RNA (mRNA) was lower, whereas that of glucose transporter 1, cluster of differentiation 36, and carnitine palmitoyltransferase‐1b mRNA was significantly higher in the Longissimus thoracis of the experimental group. Nutritional status during early post‐natal life appears to strongly influence the growth rate and glucose and lipid metabolism in Japanese Black cattle.     

Synthesis and Structure–Activity Relationships of Miticidal 4,5-Dihydropyrazole-5-thiones

A series of novel 4,5-dihydropyrazole-5-thiones (DHPs) was synthesised by treating the corresponding dihydropyrazolones with ‘Lawesson’s reagent and evaluated for miticidal activity against two-spotted spider mites (Tetranychus urticae Koch). Of these, 3-(4-chlorophenyl)-4,4-dimethyl-1-phenyl-4,5-dihydropyrazole-5-thione, 3-(4-chlorophenyl)-4-ethyl-4-methyl-1-phenyl-4,5-dihydropyrazole-5-thione, 3-(4-chlorophenyl)-1-phenyl-4,5-dihydropyrazole-5-thione-4-spirocyclopentane and 4,4-dimethyl-1-phenyl-3-(4-trifluoromethyl-phenyl)-4,5-dihydropyrazole-5-thione were highly active (pEC₅₀>4·0) and were more effective than the miticide dicofol (pEC₅₀=3·879), which has traditionally been used for the control of phytophagous mites. Structure–activity relationship (SAR) studies were performed on each position of the pyrazole ring of DHPs. The results indicated that the unsubstituted phenyl, 4-substituted phenyl and thioxo groups on the 1-, 3- and 5-positions of DHPs respectively were required for activity. Quantitative SAR studies using physicochemical parameters of substituents and the capacity factor k′ as a hydrophobicity index suggested that: (a) the activities of all types of DHPs examined were mainly dominated by hydrophobicity, (b) the bulkiness of 4-substituents of the 3-phenyl ring favoured the activity and (c) the log k′ optimum for all DHPs was 1·675, equivalent to a log P_ow value of c. 5·0.     

Malignant pinealoma observed in the deep cerebral parenchyma of a male Wistar rat

This report describes a case of spontaneous malignant pinealoma in a 90-week-old male Wistar rat. The tumor mass occurred in the deep cerebral parenchyma and no intact pineal gland was observed in the area between the posterior-dorsal median line of the cerebrum and the cerebellum. The tumor was characterized by a large nodular proliferation occupying the central area of the brain, extending from the dorsal surface to the base of the brain, corresponding to the thalamus. The tumor cells had round to irregular oblong nuclei approximately 5–17 μm in diameter and showed faintly or moderately eosinophilic cytoplasm and indistinct cell boundaries. Immunohistochemically, the tumor cells were positive for synaptophysin and partially positive for neuron-specific enolase (NSE). The tumor showed malignant features including cellular pleomorphism, high mitotic index, necrotic foci, and invasive and extensive growth and was, therefore, diagnosed as an extremely rare malignant pinealoma in the deep cerebral parenchyma.     

Post-molt processes of cuticle formation and calcification in the Japanese mitten crab <Emphasis Type="Italic">Eriocheir japonicus</Emphasis>

This study examines the following in the Japanese mitten crab: (1) the structure of the exoskeleton with special reference to its calcification; (2) the progression of post-molt cuticle formation and calcification. In the crab, the structure and calcification state of the exoskeleton at the molt and during the inter-molt stage were similar to those of other crustaceans. During the inter-molt, the exoskeleton consisted of four cuticle layers; the outermost epicuticle, the exocuticle, the endocuticle and the innermost membrane layer. Intense calcification was observed in the exo- and endocuticle. At the molt, the synthesis of the epi- and exocuticle was already complete, and the addition of the endocuticle began after the molt. Calcification of the exocuticle initiated soon after the molt, but there was a delay between endocuticle matrix synthesis and calcification. Histology showed that the process of calcification was similar to that in other crustaceans. However, calcium concentrations within the exoskeleton continued to increase and never reached the levels of the inter-molt stage at the end of the experiment. This suggests that the Japanese mitten crab is relatively slow to calcify compared to other crustaceans.     

Studies on the green liver in cultured red sea bream fed low level and non-fish meal diets: Relationship between hepatic taurine and biliverdin levels

SUMMARY: The aim of this study was to investigate the cause of green liver in red sea bream fed substitute protein diets. Red sea bream Pagrus major was given either of the following diets for 28 weeks: (1) control diet (50% fish meal), (2) low level fish meal diet (15% fish meal), and (3) non-fish meal diet (0% fish meal). The green liver was observed in all groups tested, but the incidence was much higher in the experimental diet groups. The feeding of substitute protein diets reduced plasma triglyceride and cholesterol levels. However, there was no significant difference in plasma hepatic enzyme activities and plasma bile salts concentration among the treatments. Fish fed the substitute protein diets showed low hepatic taurine levels with an appearance of a biliverdin in the liver. Moreover, the proportion of ditaurobilirubin to total biliary bile pigments was significantly lower in fish fed the substitute protein diets. These data indicate that feeding of substitute protein diets did not induce any cholestatic hepatobiliary obstructions and that the low hepatic taurine level was one of the probable factors responsible for the occurrence of green liver in red sea bream fed substitute protein diets.     

Direct evidence of multiple paternities in natural population of viviparous Japanese surfperch by allelic markers of microsatellite DNA loci

This study was performed to obtain information on the occurrence of multiple paternities in three species of viviparous Japanese surfperch using allelic markers of microsatellite DNA loci. Direct evidence for multiple fertilizations was established by reconstructing paternal genotypes from the progeny of gravid females. Multiple paternities were ascertained in five of 10 broods of Ditrema temmincki and in three of nine broods of Neoditrema ransonneti, but not in Ditrema viride. The number of patrilines detected in the progeny of D. temmincki and N. ransonneti females were two or three, respectively, as determined by the GERUD v2.0 algorithm for reconstructing parental genotypes from half-sib progeny arrays.     

Oral administration of β-alanine modifies carnosine concentrations in the muscles and brains of chickens

Carnosine, and its derivative anserine, are known to function as anti‐oxidants and putative neurotransmitters. They are especially rich in the breast muscle (Musculus pectoralis superficialis, MPS) of chickens. To clarify whether the concentrations of carnosine and anserine are altered by dietary management, the effect of oral administration of their constituent, β‐alanine (β‐Ala), was determined in the MPS and brains of chickens. Birds were orally administered β‐Ala (22 mmol/kg) twice a day for five consecutive days (from 2 to 6 days old). In the MPS, carnosine was increased by β‐Ala, whereas anserine and taurine were decreased. The concentrations of other free amino acids in the MPS were also modified by β‐Ala. In the brain, the oral administration of β‐Ala increased anserine and carnosine and decreased taurine, but caused no changes to other free amino acid concentrations. These results suggest that orally administered β‐Ala increases carnosine concentrations in both the MPS and brains of chickens. However, the effects of β‐Ala on other concentrations differ depending on the tissues.     

The normal development of Mongolian gerbil foetuses and, in particular, the timing and sequence of the appearance of ossification centres

To elucidate the normal development and growth of Mongolian gerbils, the timing and sequence of the appearance of ossification centres within foetuses were investigated. Average foetus body weight and tail length on the 15th day of pregnancy were found to be 0.042 g and 6.2 mm, respectively. For the 25th day of pregnancy, these measurements were 2.601 g and 29.4 mm, respectively. The body weight and tail length of foetuses increased significantly from the 20th day of pregnancy. Also, the first ossification centre of Mongolian gerbil foetuses appeared in the clavicle at the 17th day of pregnancy. The order in which ossification centres appeared in Mongolian gerbils resembles the pattern for rats and mice, except in some areas of the skull. Except for the clavicle, in which ossification centres appeared rather early, most ossification centres appeared in the last quarter of pregnancy. These results suggest that Mongolian gerbil foetal development is near completion by the last gestational stage. Also, ossification centres appear sooner in the skull and nasal bones than in other rodents.