IRANIAN JOURNAL OF VETERINARY RESEARCH (IJVR)
Year:2014 | Volume:15 | Issue:1 (46)|Papers Count:20

Coxiella burnetii is the etiological agent of coxiellosis in animals and Q fever (a zoonotic disease) in humans. Cattle, sheep and goats are the main reservoirs of infection for humans. This serological survey was conducted to determine the seroprevalence of coxiellosis in sheep and goat populations in Khorasan Razavi province, Iran. Four hundred and sixty animals (255 sheep from 29 herds in 12 counties and 205 goats from 28 herds in 11 counties) were selected using multi-stage cluster random sampling. Sera were assayed for antibody against C. burnetii using a Q fever ELISA kit. Seroprevalence of C. burnetii at animal level was 36.5% (95% CI: 30.6%-42.4%) for sheep and 29.8% (95% CI: 23.8%-36.2%) for goat populations. The proportion of seropositivity for sheep and goats in the studied counties ranged from 4.5%-72.7% and 6.7%-57.1%, respectively. In 26 (89.6%; 95% CI: 78.6%-100%) sheep and 22 (78.5%; 95% CI: 63.5%-93.5%) goat flocks, at least one seropositive case was detected. Logistic regression model showed that age and location correlated with seroprevalence of the antibody against C. burnetii at the individual level in both species (P<0.05). There was no difference in seroprevalence between sheep and goat populations (P=0.147). This study showed that a relatively high proportion of animals are seropositive to C. burnetii. Considering the economic and public health importance of C. burnetii in animals and humans, measures are to be implemented to prevent its spreading and to reduce the zoonotic risk of C. burnetii in the studied region.

The study was conducted to demonstrate expression profile of cold shock protein genes; cold inducible RNA binding protein (CIRP) and RNA binding motif protein 3 (RBM3) in goats (Capra hircus) during different seasons to check the gene expression in different thermal conditions. Blood samples were collected from healthy goats of tropical and temperate region during peak winter, moderate season and peak summer. Goats were divided in three (n=6 in each group) age groups- (I) up to 2 years, (II) 2 to 5 years and (III) above 5 years. RNA isolation was done from separated peripheral blood mononuclear cells (PBMCs) by Trizol reagent. Real-time PCR was applied to investigate mRNA expression of examined factors. The mRNA expression of CIRP and RBM3 was higher in all age groups during peak winter season as compared to peak summer season in both tropical and temperate region goats. To conclude, our results demonstrated expression of CIRP and RBM3 mRNAs in caprine PBMCs and increased expression of these genes during winter season could possibly play a significant role to ameliorate deleterious effects of cold stress to maintain cellular homeostasis in goats.

Phylogenetic analysis has shown that Escherichia coli is composed of four main phylogenetic groups (A, B1, B2 and D). Characterization of phylogenetic groups is of clinical interest, as group A and B1 generally associated with commensals, whereas most enteropathogenic isolates are assigned to group D, and group B2 is associated with extra-intestinal pathotype. One hundred E. coli strains recovered from faecal samples of dog, chicken, ruminants (sheep, goat and cattle) and human were subjected to phylogenetic analysis based on triplex PCR method, according to a combination of three genetic markers chuA, yjaA and DNA fragment TspE4.C2. The majority of collected isolates belonged to group D (44%), followed by groups A (32%), and B2 (24%). By sample origin, groups D, A, and B2 were prevalent in 16.7, 50, and 33.3%, respectively for dog isolates; 52.8, 36.1, and 11.1% for chicken isolates; 41.2, 29.4, and 29.4% for ruminants isolates; and 60.9, 8.7, and 30.4% for human isolates, respectively and none of the strains among all the analysed hosts belong to group B1. This study suggests there was a significant difference in the E. coli phylogenetic groups, subgroups and genetic markers among the different hosts analysed.

The pharmacokinetic parameters of ceftazidime, a third generation cephalosporin, were investigated in six buffalo calves after single intravenous (IV) and intramuscular (IM) administration at a dose rate of 10 mg/kg body weight. Ceftazidime concentrations in plasma and urine were determined by microbiological assay. Ceftazidime disposition was best fitted by a two-compartmental and a one-compartmental open model with first-order elimination after IV and IM dosing, respectively. After IV administration, distribution was rapid (t1/2a=0.15±0.01 h) with an area under the ceftazidime plasma concentration/time curve (AUC0-¥) of 253.9±7.8 mg/ml.h and a steady state volume of distribution (Vd (ss)) of 0.18±0.01 L.kg-1. The elimination half life (t1/2b) and total body clearance were 3.4±0.2 h and 39.5±1.2 ml/kg/h, respectively. Following intramuscular administration, the absorption half life (t1/2ka), peak plasma concentration (Cmax), time to peak plasma concentration (Tmax), AUC0-¥ and bioavailability were 0.25±0.04 h, 45.8±2.7 mg/ml, 0.75 h, 207.9±9.9 mg/ml.h and 81.7±5.9%, respectively. Urinary excretion of ceftazidime was less than 55% 36 h post administration. In vitro plasma protein binding of ceftazidime was 13.1±1.1%. To maintain minimum therapeutic concentration of 4 mg/ml, a satisfactory dosage regimen of ceftazidime in buffalo calves would be 9.4 mg/kg to be repeated at 12 h intervals. In conclusion, ceftazidime (10 mg/kg, IM) shows favorable pharmacokinetic behavior in buffalo calves.

The present work was carried out to study the effect of vacuum packaging and pomegranate peel extract (PE) treatments on the quality of pacific white shrimp (Peneous vannamei) during refrigerated storage. Changes in pH, thiobarbituric acid (TBA), total volatile base nitrogen (TVB-N), trimethylamine (TMA), aerobic plate counts, psychrophilic, lactic acid bacteria and enterobacteriaceae counts, melanosis and sensory characteristics were investigated in up to 10 days of storage at 4oC. Microbial growth of vacuum packed and PE treated (1 or 2%) shrimps were retarded during storage time in comparison with the control group (P<0.05). Furthermore, use of PE in combination with vacuum packaging enhanced the antimicrobial effect of vacuum packaging against the bacterial populations. Vacuum packaging demonstrated a significant reduction in TVB-N, TMA and TBA content of shrimps during refrigerated storage. However, use of vacuum packaging and PE in combination did not significantly improve chemical parameters of the samples. Hence, vacuum packaging is considered as an effective method to extend the shelf-life of shrimp and, when combined with PE, can dramatically improve the overall likeness and microbial quality of the product.

This study was conducted because of influence of prebiotics (alphamune) and symbiotic (biomin) on histometrical development of small intestine and lymphatic tissue of caecal tonsil have been not reported on broiler chicken. In this study, different parts of small intestine and caecal tonsil, which is a major area of gut associated lymphatic tissue (GALT) in chicken were selected. One hundred and twenty-five 1-day-old broiler chicks were divided into 3 groups: 1) Control group which were fed only by basal diet, 2) Alphamune group which were fed basal diet supplemented with prebiotic (0.5 kg/ton alphamune), and 3) Biomin group, fed basal diet supplemented with symbiotic (1 kg/ton biomin). At the end of 42 days, 15 chicks (5 chicks from each group) were selected for histomorphometrical study. The samples were taken from different parts of small intestine (duodenum, jejunum and ileum) and caecal tonsils and fixed in 10% formalin. The 5-6 μ sections were made by paraffin embedding method and stained by H& E. The results showed that although alphamune and biomin have a significant improvement on histomorphological structure of small intestine (more significant changes were seen in duodenum) and lymphatic tissue of caecal tonsil, the biomin has a more significant improvement. Villous height and thickness, the number of goblet cells, number and depth of intestinal crypt, density and area of aggregated lymphatic tissue were increased more significantly in biomin group (P<0.05). The knowledge obtained from this study showed that alphamune and biomin are considerable feed additives instead of antibiotic for improvement of histomorphological structure of small intestine and its associate lymphatic tissue.

Botulism is a serious paralytic disease caused by Clostridium botulinum toxin in foods. There are seven recognized serotypes of botulinum neurotoxins among which the principal prevalent types in humans include A, B and E. Infant botulism results from intestinal colonization and toxin production by C. botulinum spores in babies less than 1 year old. Honey is the most important food discriminated as the cause of infant botulism. In this study, a total of 100 honey samples were collected from retail markets in Shiraz, Iran and analysed for the presence of C. botulinum using a multiplex PCR assay. Three pairs of primers were designed and optimized to identify A, B and E strains in the specimens. Positive samples were further examined to find out whether they carried the toxin gene; toxin products were also checked by mouse bioassay. The results showed that out of 100 honey samples tested, 2% were found positive for type B which carried the neurotoxin B gene confirmed by sequencing. All the injected mice died, whereas no symptoms were observed in the control groups. The honey collected from Shiraz retail markets was contaminated with the spore of the bacteria and can thus potentially cause infant botulism. Bioassay is described as a standard method; however, molecular based techniques also easily, quickly and reliably detect C. botulinum, its toxins and spores in food stuffs and is strongly advised for use in the food microbial lab.

The polymerase chain reaction (PCR) was used to amplify a 578 bp fragment of the poxvirus 4b core protein. Avipoxvirus (APV) specific DNA was detected in all 10 different isolates (each of which had been isolated from an epidemic) isolated from chicken; canary and mynah were collected from Tehran province. Sequencing was performed for 2 isolates as representative and the nucleotide sequence showed a similarity of 71-100% with the other sequences in the GenBank. The derived phylogenetic tree showed six distinguishable sequence clusters. The sequence analysis reveals that the Iranian isolates are within the cluster with highly conserved p4b core protein in different countries and species of birds. Concerning the distance between countries which is the origin of the studied isolates that are situated in the same cluster with our Iranian isolates, nearly the same identity (95-99%) of isolates in this cluster exist, and so potential of infectivity of the isolates in several species and regions, and the import and export of birds from all over the world can likely spread the virus to other countries. Hence, strict quarantine measures should be considered in the entrances of every country. Moreover, this is the first molecular study in Avipoxviruses in Iran, especially in exotic birds.

Cyprinus carpio is a stenohaline species but can tolerate some ranges of changes in environmental salinities, so histomorphological methods and Na+-K+ ATPase and Aquaporin 3 immunohistochemistry were performed on common carp kidney as an osmoregulatory organ in experimental groups and control in order to investigate their possible roles during salinity challenge. Five groups of fish (n=25) with salinities ranging from 3, 6, 9 and 12 g/l marine salt and a control group (tap water) were used. The experiment was continued for two weeks. Kidney samples from control and experimental groups were fixed in 4% paraformaldehyde and were embedded in paraffin. The Na+-K+ ATPase and Aquaporin 3 intensity of the immunostaining and the renal tubules dilation had direct relation with environmental salinities, and showed the involvement of these proteins in physiological responses to environmental salinity. Furthermore, in the salinities 9 and 12 g/l epithelium of the renal tubules, profound histomorphological alteration was present.

Anaplasma ovis infections can cause severe anemia in the acute phase of the disease. In order to investigate the alterations of erythrocyte protective antioxidant mechanisms associated with anemia in sheep experimentally infected with A. ovis, 100 ml heparinized blood was collected from splenectomised sheep that showed 6% A. ovis parasitemia. Inoculums of 20 ml blood were administered intravenously to five male sheep without any blood parasite. Parasitological and haematological changes and the activities of erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were studied in experimentally infected animals on the 0-38 post infection days. Parasitemia increased significantly with the progress of infection and reached its maximum level on day 15 of the experiment. From this point to day 38, there was a gradual decline in parasitemia. A significant decrease in PCV, RBC and Hb concentration was evident coincidentally with peak parasitaemia in the infected sheep. On post infection day 15, the activities of all enzymes increased, the changes being significant for SOD activity. There was a significant positive correlation among parasitemia and the activities of erythrocyte SOD (r=0.644, P<0.0005) and CAT (r=0.424, P<0.05). Glutathione peroxidase activity declined significantly between post infection days 23-38. From the present study, it can be concluded that oxidative stress has an important role in anemia induced by anaplasmosis in sheep. It seems that SOD is a useful indicator of oxidative stress caused by A. ovis infection, due to its constant increasing means in the course of the disease.

Canine ehrlichiosis has emerged as one of the most clinically important tick-borne diseases affecting dogs. Eighty-five naturally infected dogs have been investigated, the most consistent clinical signs recorded were fever, emaciation and lymphoadenopathy, anemia, monocytosis, thrompocytopenia, hypoalbuminemia, elevation in liver enzymes and total bilirubin were the most remarkable changes associated with canine ehrlichiosis in Egyptian dogs; microscopic examination failed to provide definitive diagnosis of canine ehrlichiosis. Season did not greatly influence the disease; the type of ticks involved in the disease transmission in Egypt was Rhipicephalus sanguineus.

The objective of the current study was to evaluate the reproducibility of a reverse transcriptase PCR (RT-PCR) -based technique to differentiate viable and dead Salmonella cells in raw and sterilized milk. The microorganism was initially inoculated into the milk samples followed by incubating at 37°C for 4 h prior to inactivation by heat at 80oC for 10 min. The treated and non-treated samples were subsequently monitored using both PCR and RT-PCR, in vitro. Following 4 h incubation, the invA gene of Salmonella was clearly amplified by RT-PCR, while no band was detected in the heated samples. On the other hand, using the conventional PCR, it was possible to amplify the gene in both samples. Our results may suggest an important application of the RT-PCR technique, especially when the number of live organisms is an imperative factor to produce food borne infections and to establish a detection limit of the test.

Mastitis is one of the most serious and costly diseases affecting dairy cattle production. In the present study, effects of a lactoferrin gene polymorphism (intron 6) on milk somatic cell count (SCC) and subclinical mastitis was investigated in 121 Holstein dairy cattle. Two alleles of A and B and two genotypes of AA and AB were found in an EcoRI recognized single nucleotide polymorphism in intron 6 of lactoferin gene with the frequencies of 85.12, 14.88, 70.25 and 29.75%, respectively. No homozygous BB cows were detected in the studied population. Marker-traits association analysis showed that EcoRI marker site in lactoferrin gene was significantly related to SCC (P0.01) with AB as a desirable genotype. The obtained results in the present study indicated that selection of the AB genotypes for EcoRI recognized single nucleotide polymorphism might contribute to a reduction of SCC in Holstein dairy cattle.

The effect feeding olive-pulp silage (OPS) for 120 days on several blood attributes was studied using 16 rams allotted to two diets consisting of 70% corn silage or 70% OPS. Olive-pulp silage feeding resulted in lower serum total protein, alanine aminotransferase, calcium and phosphorus levels and higher glucose concentration compared to the corn silage diet. Body weight and other blood attributes were not affected by OPS feeding. Feeding a diet containing 70% OPS at the maintenance level had no apparent detrimental effect in mature rams.

This scientific report describes the effect of feeding detoxified karanj seed cake as protein replacement of soya bean meal on immunity and pathology in growing lambs. Twenty-four male lambs, 4-6 months of age were divided into four groups of six each and fed with different levels of detoxified karanj seed cake (dKC 0%, dKC 25%, dKC 50%, dKC 75%) for 140 days. Effect on humoral and cell mediated immunity was assessed by antibody titer against Peste des petites ruminants (PPR) vaccination and lymphocyte proliferation assay, respectively. Significant decrease in the humoral immunity in high dose fed group and no change in stimulation index of lymphocytes in all the groups were observed. On histopathology, dKC 75 showed severe changes in intestine, testis and mesenteric lymph node. Thus, the present process of detoxification of karanj seed cake is useful for feeding growing lambs up to 50% protein replacement levels, with little adverse effect on immunity and pathology.

Infectious keratoconjunctivitis (IKC) is a painful, highly contagious ocular disease in sheep and goats. This study was carried out for identification and characterization of causative agent of ocular disease in a sheep flock consisting of 300 ewes in Mashhad, Iran. Several ocular swabs were taken from affected animals. The samples were pooled and processed in a laboratory for isolation of suspecious agent. Following inoculation of the pooled sample in PPLO broth and agar, turbidity and growth of colonies were observed in them, respectively. Sequencing of the 1013 bp PCR product of 16S rDNA gene revealed that the causative agent of the outbreak has 100% sequence identity to Mycoplasma conjunctivae. Based on our knowledge this is the first documented report of isolation and molecular characterization of M. conjunctivae in Iran.