Prediction of B cell and T-helper cell epitopes candidates of bovine leukaemia virus (BLV) by in silico approach.

The bovine leukaemia virus (BLV) is a retrovirus responsible for enzootic bovine leukaemia (EBL) disease, the most common cattle disease leading to high annual economic losses to the cattle breeding industry. Virus monitoring among the sheep and cattle herds is usually done by vaccination. Inactivated virus vaccines can partially protect the livestock from viral challenge. However, vaccinated animals are likely to be infected. So, there is an essential need for producing vaccine by other methods. Gp60 SU, encoded by Env gene, is the surface glycoprotein of BLV detected to be the major target for the host immunity against the virus. Different stages were performed to predict the potential B and T-helper cell epitopes. The general framework of the method includes retrieving the amino acid sequence of gp60 SU, conducting the sequence alignment, getting the entropy plot, retrieving the previously found epitopes, predicting the hydropathy parameters, modelling the tertiary structure of the glycoprotein, minimizing the structure energy, validating the model by Ramachandran plot, predicting the linear and discontinuous epitopes by various servers and eventually choosing the consensus immunogenic regions. Ramachandran plot scrutiny has demonstrated that the modelled prediction is accurate and suitable. By surveying overlaps of various results, 4 and 2 immunogenic regions were selected as linear and conformational epitopes respectively. Amino acids 35-53, 67-97, 288-302 and 410-421 and those of numbers 37-58 and 72-100 were the regions selected as linear and conformational epitopes respectively. The tertiary structure of the final epitope was modelled as well. A comparison of the predicted epitopes structure with that of gp60 SU envelope, illustrated that the tertiary structure of these epitopes does not change after being separated from the primary complete one. The present achievements will lead to a better interpretation of the antigen-antibody interactions against gp60 in the designing process of safe and efficient vaccines.

Reproductive characteristics and thyroidal function in relation with season in Khuzestan buffalo (Bubalus bubalis) bulls.

High ambient temperature is the major constraint on Buffalo productivity. The aim of this study was to evaluate the reproductive performance and thyroid gland function in winter and summer seasons in Khuzestan buffalo bulls. Six male indigenous buffaloes of Khuzestan with nearly the same age (2-3 years old) and weight were used. Semen and blood samples through jugular vein were collected, every two weeks throughout the summer and winter seasons. The thyroid hormones and thyrotropin stimulating hormone (TSH) concentration in blood serum were measured by radioimmunoassay method. Semen quality was determined, using computer assisted sperm analyzer (CASA) and routine methods. The concentration of thyroxin (T4) was lower in winter than summer (p ≤ 0.05). The level of T3 uptake was higher in cold season than that of in hot season (p ≤ 0.05). The differences of tri-iodotyronine (T3) and TSH concentrations, as well as free thyroxin index were not significant between seasons. The semen volume and spermatozoa parameters including concentration, progressive motility, linear velocity, mean velocity, beat cross frequency, linear coefficient and straightness coefficient were higher in winter than summer (p ≤ 0.05). Semen pH and amplitude of lateral head displacement of spermatozoa were higher in summer than winter (p ≤ 0.05). In winter, there was positive correlation between spermatozoa concentration and T3 value of blood serum (p ≤ 0.05). There were positive correlations between values of semen volume and T4, progressive spermatozoa motility percent and TSH, as well as, total motility of spermatozoa and TSH in summer (p ≤ 0.05). In general, thyroid function and semen quality of Khuzestan buffaloes may be affected by seasons.

Defense cells profile of cervical mucous during follicular and luteal phases of estrus cycle in river buffalo.

The aim of this study was to evaluate the defense cells changes of cervical mucous during follicular and luteal phases of estrus cycle in river buffalo. Reproductive organs of the adult and apparently healthy female buffaloes were collected from the slaughterhouse. By visual investigation of both the ovaries for presence of corpus luteum and growing follicles, the luteal and follicular phase of each buffalo was specified. Cervical discharge samples were collected by sterile swabs and then spread over the glass slides, dried and fixed with methanol. The specimens were undergone Giemsa staining. The percentage of lymphocytes, neutrophils, monocytes (macrophages), eosinophils and basophils in each case (for both the follicular and luteal phases) were obtained at 20 microscopic fields. The percentage of lymphocytes, neutrophils and basophils in luteal phase were higher than the follicular phase. The percentage of eosinophils in follicular phase was higher than the luteal phase. The percentage of monocytes (macrophages) in luteal and follicular phases was nearly equal. The statistical analysis showed that the differences of all cells between follicular and luteal phase were not significant (P > 0.05). The most defense cells in discharges of external os of cervix (both follicular and luteal phases) were neutrophils and lymphocytes.