Cell lines originating from horses are necessary for isolation and propagation of equine herpesviruses (EHV). Although we established an equine-derived cell line, FHK-Tcl3, propagation ceased after fewer than 40 passages. In this study, FHK-Tcl3 cell propagation continued beyond 40 passages, achieving over 100 passages. FHK-Tcl3 cells were then cloned by limiting dilution at the 100th passage. Cloned cells were termed FHK-Tcl3.1. FHK-Tcl3.1 cells grew well and were propagated every 3 to 4 days by splitting 1:5. In addition, EHV-1, -2 and -4 showed a clear cytopathic effect (CPE) in FHK-Tcl3.1 cells, and this CPE was very similar to those seen in parental FHK-Tcl3 and primary fetal horse kidney cells. FHK-Tcl3.1 cells continue to propagate and the current passage record is over 100 times after cloning. Therefore, this cell appears to have been immortalized. FHK-Tcl3.1 cells have potential for growth and diagnosis of various equine viruses, including equine herpesviruses.
At 114 ranches in the Hidaka District of Hokkaido, a total of 1,118 Thoroughbred foals that were born from January to June 2003 were examined at different times from May to September of the same year to ascertain the occurrence of clubfoot. Clubfoot was seen in a total of 179 foals (16%) at 89 ranches (78%). Also, 124 of the 179 foals (69.3%) had clubfoot of grade II or higher, and it was found that grade I was likely to be overlooked or rapidly advance. In the present study, the occurrence of clubfoot was higher than expected in the investigated region. Hence, it is necessary to establish accurate diagnostic techniques and clubfoot guidelines to minimize the impact.
The purpose of this study was to evaluate the effect of the canine cranial cruciate ligament repair system on laryngeal hemiplegia in heavy draft horses. Twenty-four heavy draft horses diagnosed with grade 4 laryngeal hemiplegia were allocated to either the prosthetic laryngoplasty (PL) group (n=14) or a canine cranial cruciate ligament repair system (CCCLRS) group (n=10). Right to left angle quotients (RLQs) of abductions of the arytenoid cartilages were endoscopically evaluated before and after surgery. Post-operative RLQs in the CCCLRS group were significantly lower than those of the PL group (P<0.01). The canine cranial cruciate ligament repair system was revealed to be a good surgical procedure for laryngeal hemiplegia in heavy draft horses.