The relationship between plasma leptin concentrations and the distribution of body fat in crossbred steers

The objective of the present study was to examine the relationship between plasma leptin levels and fat distribution in crossbred steers. Twenty-four crossbred steers (Japanese Black × Holstein) were used in this study. Six steers belonged to the growing phase (11 months of age), and 18 steers to the finishing phase (from 21 to 28 months of age). Plasma leptin levels correlated positively with body fat weight ( r  = 0.807, P  < 0.01), body fat percentage ( r  = 0.802, P  < 0.01), visceral fat weight ( r  = 0.807, P  < 0.01), visceral fat percentage ( r  = 0.780, P  < 0.01), subcutaneous fat weight ( r  = 0.745, P  < 0.01), subcutaneous fat percentage ( r  = 0.734, P  < 0.01), intermuscular fat weight ( r  = 0.793, P  < 0.01), intermuscular fat percentage (0.775, P  < 0.01), renal fat weight ( r  = 0.694, P  < 0.01), renal fat percentage ( r  = 0.642, P  < 0.01), subcutaneous fat thickness ( r  = 0.755, P  < 0.01), intermuscular fat thickness ( r  = 0.721, P  < 0.01), beef marbling score ( r  = 0.706, P  < 0.01) and the crude fat content of Musculus longissimus thoracis ( r  = 0.592, P  < 0.01). The location of fat deposits did not affect the correlation values. However, when steers were divided into growing ( n  = 6) and finishing ( n  = 18) groups, there was no significant correlation between plasma leptin levels and the carcass characteristics related to fat deposition (fat weight, fat percentage, carcass traits) in either group. These results suggest that plasma leptin levels in crossbred steers positively correlate with body fat content and carcass traits when these parameters vary widely.     

Effect of supplementation with the reduced form of coenzyme Q10 on semen quality and antioxidant status in dogs with poor semen quality: Three case studies

Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs.     

Methods of evaluating the spermatogenic ability of male raccoons (Procyon lotor)

Feral raccoons (Procyon lotor) have been growing in number in Japan, and they are becoming a problematic invasive species. Consequently, they are commonly captured and killed in pest control programs. For effective population control of feral raccoons, it is necessary to understand their reproductive physiology and ecology. Although the reproductive traits of female raccoons are well known, those of the males are not well understood because specialized knowledge and facilities are required to study them. In this study, we first used a simple evaluation method to assess spermatogenesis and presence of spermatozoa in the tail of the epididymis of feral male raccoons by histologically examining the testis and epididymis. We then evaluated the possibility of using 7 variables—body weight, body length, body mass index, testicular weight, epididymal weight, testicular size and gonadosomatic index (GSI)—to estimate spermatogenesis and presence of spermatozoa in the tail of the epididymis. GSI and body weight were chosen as criteria for spermatogenesis, and GSI was chosen as the criterion for presence of spermatozoa in the tail of the epididymis. Because GSI is calculated from body weight and testicular weight, this model should be able to be used to estimate the reproductive state of male raccoons regardless of season and age when just these two parameters are known. In this study, GSI was demonstrated to be an index of reproductive state in male raccoons. To our knowledge, this is the first report of such a use for GSI in a member of the Carnivora.     

Paragonimus westermani metacercariae in two freshwater crab species in Kagoshima Prefecture,Japan, as a possible source of infection in wild boars and sika deer

Paragonimiasis is a particular foodborne parasitic disease that is endemic to southern Kyushu, including Kagoshima Prefecture, Japan. We previously detected Paragonimus westermani triploid larvae in meat samples obtained from wild boars and sika deer hunted in Akune City, Kagoshima Prefecture. These mammals act as paratenic hosts and their meat is a source of human paragonimiasis. Paratenic host mammals and humans become infected with the lung fluke, P. westermani, following consumption of second intermediate hosts, freshwater crab species, namely, Geothelphusa dehaani or Sawagani in Japanese, and Eriocheir japonica or Mokuzugani in Japanese. Therefore, this study aimed to investigate the current infection status of P. westermani in freshwater crabs in Akune City. We collected freshwater crabs from 15 locations and found that the prevalence of P. westermani metacercariae was 1.6% for Sawagani (15 of 941 examined) and 22.1% for Mokuzugani (21 of 95 examined). Based on the morphological characterization of metacercariae and molecular analyses of the internal transcribed spacer 2 region and mitochondrial 16S rRNA gene region using PCR-restriction fragment length polymorphism and sequencing, all metacercariae were identified as the triploid form of P. westermani. These results indicate that Sawagani and Mokuzugani serve as second intermediate hosts to maintain the life cycle of triploid P. westermani. Further, infection in crabs potentially leads to subsequent P. westermani infections in wild mammals, including wild boars and sika deer, both of which are considered important types of game meat in Japan.     

Therapeutic effects of vitamin E supplementation in 4 dogs with poor semen quality and low superoxide dismutase activity in seminal plasma

Four dogs with poor semen quality, low seminal plasma superoxide dismutase (SOD) activity and low blood plasma testosterone (T) levels were orally administered one vitamin E tablet containing 50 mg α-tocopheryl acetate per dog daily for 4 weeks. The mean values of semen quality were temporarily improved after the start of vitamin E treatment and the values of 4, and 5 weeks after that were significantly different from those before the treatment (P<0.05–0.001). The mean blood plasma T and seminal plasma SOD activity values slightly increased in the 4 dogs after the treatment. The results of the present study indicate that poor semen quality in dogs with low seminal plasma SOD can be improved by vitamin E treatment.     

Protective effect of sodium glutamate and sorbitol on thermal denaturation of chicken and croaker actomyosin

The thermal protective effect (E‐Value) of sodium glutamate (Na‐Glu) on chicken and croaker actomyosin (AM) was significant but decreased slightly with increasing concentration. The E‐value of chicken AM with Na‐Glu was 1.11 mol/L^?1 at 0–0.75 mol/L and decreased to 0.4 mol/L^?1 at 0.75–1.5 mol/L. Likewise, the E‐value of croaker AM with Na‐Glu was 1.51 mol/L^?1 at 0–1 mol/L and decreased to 0.2 mol/L^?1 at 1–1.5 mol/L. Sorbitol showed a steady thermal protective effect on chicken and croaker AM. The E‐values of chicken and croaker AM at 0 to 1.5 mol/L sorbitol were 0.71 mol/L^?1 and 0.59 mol/L^?1, respectively. The protective effect of sorbitol on both types of AM was greater than that of Na‐Glu. Higher concentrations of Na‐Glu with chicken and croaker AM gave a decrease in viscosity number and turbidity. Higher concentrations of Na‐Glu caused internal aggregation of AM and the protective effect of Na‐Glu was decreased. The results of this experiment confirmed that Na‐Glu and sorbitol have different modes of action and ability to control the thermal denaturation of chicken and croaker AM.     

Influence of different methods of collection from the canine epididymides on post-thaw caudal epididymal sperm quality

Canine epididymal sperm was collected from the cauda epididymis using 2 different methods (flushing and mincing) to compare the qualities (the percentage of progressively motile, viable, morphologically abnormal, immature and intact acrosomes) before and after freezing and thawing. No significant difference was noted in the quality of the cauda epididymal sperm immediately after collection and after freezing-thawing between the collection methods, although the mean levels of sperm quality with the flushing method were slightly better than that of the mincing method. The flushing method is simple and free of blood contamination, although the vas deferens was too small to be perfused in only 1 dog, and our results suggest that the flushing method is preferable to the mincing method for collecting sperm from the canine cauda epididymis.