Nodavirus associated with pathological changes in adult spotted coralgroupers (Plectropomus maculatus) in Thailand with viral nervous necrosis

The present study characterized viral nervous necrosis in sea cage-reared adult spotted coralgroupers (Plectropomus maculatus). Histopathological study showed extensive vacuolation and neuronal necrosis of the olfactory bulb and the optic lobe of the forebrain and the inner and outer nuclear layer of retina. Mild necrosis was observed in the spinal cord. Homogeneous intranuclear inclusion bodies were noted in the hyperplastic and hypertrophic glandular epithelial cells of the swim bladder suggesting viral etiology. Etiological diagnosis of VNN was confirmed by RT-PCR, immunohistochemistry and in situ hybridization. The immunohistochemistry and in situ hybridization gave strongly positive staining in the same area of the infected cells of the brain, spinal cord and retina correlating with histopathological changes. No positive reaction was detectable in the affected gas glandular epithelium and other organs, confirming the consistent neurotropism of this nodavirus. Nodavirus was mainly detected in the olfactory bulb of the brain. The result suggests nasal transmission was the major route of infection.     

Leptin receptor expression and its change in association with the normalization of EGF profile after seminal plasma treatment in repeat breeder dairy cows

Factors associated with high milk production levels have been linked to alterations in the endometrial epidermal growth factor (EGF) profile, a cause of reduced fertility in dairy cows. Therefore, we examined the leptin system that connects nutritional status and reproduction in dairy cattle related to reduced fertility in repeat breeder cows. Plasma leptin concentrations were measured in 18 heifers, 20 high-yielding control cows, and 26 repeat breeder cows, showing an altered EGF profile. Then, all repeat breeder cows were infused with seminal plasma (SP) into the vagina at the next estrus to normalize the EGF profile, while heifers and control cows were infused with vehicle alone. All animals were examined for EGF profiles. Eighteen repeat breeder cows, nine heifers, and nine control cows were also determined for leptin receptor (Ob-R) expression levels in the estrous cycle before and after the infusion. SP normalized the EGF profile in 53.8% of the repeat breeder cows. Leptin concentrations were similar in all groups, regardless of the treatment results for the EGF profile. In contrast, Ob-R levels in repeat breeder and control cows were similar and higher than those in heifers before SP treatment. Ob-R in repeat breeders showing a normal EGF profile after treatment decreased to an intermediate level between heifers and control cows and may provide a clue to take measures against repeat breeding in dairy cows.