Genetic (co)variances and breeding value estimation of Gompertz growth curve parameters in Finnish Yorkshire boars, gilts and barrows.

This paper's objectives were to estimate the genetic (co)variance components of the Gompertz growth curve parameters and to evaluate the relationship of estimated breeding values (EBV) based on average daily gain (ADG) and Gompertz growth curves. Finnish Yorkshire central test station performance data was obtained from the Faba Breeding (Vantaa, Finland). The final data set included 121,488 weight records from 10,111 pigs. Heritability estimates for the Gompertz growth parameters mature weight (alpha), logarithm of mature weight to birth weight ratio (beta) and maturation rate (kappa) were 0.44, 0.55 and 0.31, respectively. Genotypic and phenotypic correlations between the growth curve parameters were high and mainly negative. The only positive relationship was found between alpha and beta. Pearson and Spearman rank correlation coefficients between EBV for ADG and daily gain calculated from Gompertz growth curves were 0.79. The Spearman rank correlation between the sire EBV for ADG and Gompertz growth curve parameter-based ADG for all sires with at least 15 progeny was 0.86. Growth curves differ significantly between individuals and this information could be utilized for selection purposes when improving growth rate in pigs.     

Propagation of Asian isolates of canine distemper virus (CDV) in hamster cell lines

Backgrounds

The aim of this study was to confirm the propagation of various canine distemper viruses (CDV) in hamster cell lines of HmLu and BHK, since only a little is known about the possibility of propagation of CDV in rodent cells irrespective of their epidemiological importance.

Methods

The growth of CDV in hamster cell lines was monitored by titration using Vero.dogSLAMtag (Vero-DST) cells that had been proven to be susceptible to almost all field isolates of CDV, with the preparations of cell-free and cell-associated virus from the cultures infected with recent Asian isolates of CDV (13 strains) and by observing the development of cytopathic effect (CPE) in infected cultures of hamster cell lines.

Results

Eleven of 13 strains grew in HmLu cells, and 12 of 13 strains grew in BHK cells with apparent CPE of cell fusion in the late stage of infection. Two strains and a strain of Asia 1 group could not grow in HmLu cells and BHK cells, respectively.

Conclusion

The present study demonstrates at the first time that hamster cell lines can propagate the majority of Asian field isolates of CDV. The usage of two hamster cell lines suggested to be useful to characterize the field isolates biologically.     

A review of the contemporary knowledge of bovine tuberculosis and government policy in Iran

In 1931 Carpantier reported bovine TB (BTB) in Iranian cattle. Some eighty years on with a national test-and-slaughter programme in place for over four decades, the efforts to vanquish Mycobacterium bovis (M. bovis) infection in cattle have been in vain as the vast majority of the 30 Iranian provinces still have reports of BTB in their cattle herds every year. This paper reviews the present epidemiology of BTB in Iran and in the region and evaluates the success of government policy in controlling this disease.     

Effects of Hormonal Supplementation on Nuclear Maturation and Cortical Granules Distribution of Canine Oocytes During Various Reproductive Stages

The aim of this study was to evaluate the effects of hCG, progesterone and oestradiol supplementation on nuclear and cytoplasmic maturation of canine oocytes cultured for 24, 48, 72 and 96 h. Oocytes obtained from 18 healthy bitches were divided into three groups according to their reproductive status (follicular, luteal and anoestrus stages) and cultured in TCM 199 + 25 UI/ml of hCG + 1 μg/ml of progesterone + 1 μg/ml of 17‐β oestradiol or without hormonal supplementation (control) for different periods. Then, they were stained with FITC‐LCA‐Hoescht for chromatin configuration and cortical granules distribution and evaluated under an epifluorescence microscope. Culture time and the influence of different stages of the oestrous cycle were also evaluated. The present study demonstrated that there was no significant difference among the reproductive stages. With regards to culture medium, only oocytes from the supplemented medium were able to complete meiosis; however, significant difference was only noticed in the percentage of MI stage oocytes (p < 0.05) in the follicular and luteal group at 72 h of culture. Most oocytes in germinal vesicle, germinal vesicle breakdown and metaphase I stage had cortical granules distributed throughout the cytoplasm (immature pattern), irrespective of the culture period (p < 0.05). Cortical granules distributed immediately beneath the plasma membrane (mature) was only observed in metaphase II stage oocytes, but not all of them presented matured cytoplasm. Our results reveal that cortical granules distribution in canine oocytes matured in vitro did not progressed in correspondence with nuclear stage changes and are in accordance with those from other species.     

Ultra‐frequent HRAS p.Q61R somatic mutation in canine acanthomatous ameloblastoma reveals pathogenic similarities with human ameloblastoma

Ameloblastoma is a locally aggressive odontogenic tumour that occurs in humans and dogs. Most ameloblastomas (AM) in humans harbour mutually‐exclusive driving mutations in BRAF, HRAS, KRAS, NRAS or FGFR2 that activate MAPK signalling, and in SMO that activates Hedgehog signalling. The remarkable clinical and histological similarities between canine acanthomatous ameloblastoma (CAA) and AM suggest they may harbour similar driving mutations. In this study, aimed at characterizing the mutational status of SMO, BRAF, HRAS, KRAS, NRAS and FGFR2 in CAA, we used RNA sequencing, Sanger sequencing and restriction fragment length polymorphism assays to demonstrate that 94% of CAA (n = 16) harbour a somatic HRAS p.Q61R mutation. The similarities in MAPK‐activating mutational profiles between CAA and AM implicate conserved molecular mechanisms of tumorigenesis, thus, qualifying the dog as a potentially useful model of disease. Given the relevance of RAS mutations in the pathogenesis of odontogenic tumours and other types of cancer, the results of this study are of comparative, translational, and veterinary value.