Microbiology
Bentolhoda Rahman; Abdolghaffar Ownagh; Karim Mardani; Farhad Farrokhi Ardebili
Volume 7, Issue 2 , June 2016, , Pages 155-162
Abstract
This study was conducted to investigate the prevalence of subclinical mastitis caused by Staphylococcus spp. in ewes in West-Azerbaijan province of Iran. Molecular characterization of isolated Staphylococcus spp. from diseased ewes were performed using polymerase chain reaction (PCR) followed by restriction ...
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This study was conducted to investigate the prevalence of subclinical mastitis caused by Staphylococcus spp. in ewes in West-Azerbaijan province of Iran. Molecular characterization of isolated Staphylococcus spp. from diseased ewes were performed using polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) and DNA sequencing of glyceraldehyde-3-phosphate dehydrogenase (gap) gene. Also, antibiotic resistance of staphylococcal isolates against different antibiotics was investigated. A total number of 900 milk samples from 450 native ewes in their mid-lactation period were examined by the California mastitis test (CMT). The CMT positive samples were cultured and bacteria were isolated from 86 (9.50%) glands and 74 (16.40%) ewes. The prevalence of subclinical mastitis in the examined ewes was 16.40%. Microbiological analysis of milk samples revealed that 27 out of 74 sheep with subclinical mastitis were infected with Staphylococcus spp. Amplification of gap gene of 27 Staphylococcus isolates generated a single amplicon of 933 bp in size confirming that isolates were belonged to Staphylococcus genus. Digestion of PCR products by AluI endonuclease generated different RFLP patterns for each species. Nucleotide sequencing of gap gene followed by phylogenetic analysis showed that the most dominant Staphylococcusspecies were S. epidermidis, S. xylosus and S. chromogenes. Staphylococcal isolates showed the highest resistance to penicillin and ampicillin. In conclusion, Staphylococcus species, except for the southern parts of the province, play an important role in the development of subclinical mastitis in sheep in West-Azerbaijan province of Iran. Also, chloramphenicol, ciprofloxacin and neomycin are the most effective antibiotics for treatment of this disease.
Somayeh Mostafapor; Farhad Farrokhi Ardebili
Volume 5, Issue 2 , June 2014, , Pages 101-105
Abstract
The aim of this study was to evaluate the effects of dilution rate and holding time on various motility parameters using computer-assisted sperm analysis (CASA). The semen samples were collected from three Ghezel rams. Samples were diluted in seminal plasma (SP), phosphate-buffered saline (PBS) containing ...
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The aim of this study was to evaluate the effects of dilution rate and holding time on various motility parameters using computer-assisted sperm analysis (CASA). The semen samples were collected from three Ghezel rams. Samples were diluted in seminal plasma (SP), phosphate-buffered saline (PBS) containing 1% bovine serum albumin (BSA) and Bioexcell. The motility parameters that computed and recorded by CASA include curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), straightness (STR), linearity (LIN), amplitude of lateral head displacement (ALH), and beat cross frequency (BCF). In all diluters, there was a decrease in the average of all three parameters of sperms movement velocity as the time passed, but density of this decrease was more intensive in SP. The average of ALH between diluters indicated a significant difference, as it was more in Bioexcell in comparison with the similar amount in SP and PBS. The average of LIN in the diluted sperms in Bioexcell was less than two other diluters in all three times. The motility parameters of the diluted sperms in Bioexcell and PBS indicated an important and considerable difference with the diluted sperms in SP. According to the gained results, the Bioexcell has greater ability in preserving motility of sperm in comparison with the other diluters but as SP is considered as physiological environment for sperm. It seems that the evaluation of the motility parameters in Bioexcell and PBS cannot be an accurate and comparable evaluation with SP.