Iranian Journal of Veterinary Research
Volume:9 Issue: 3, Summer 2008

The protective capacity of the crude extracts from larval and nymphal stages of Hyalomma anatolicum anatolicum was examined in the New Zealand white rabbits. The rabbits were randomly divided into 3 groups of five animals. The rabbits in groups 1 and 2 were immunized with crude extracts of larval and nymphal antigens, respectively and group 3 was served as control. Following challenge of each rabbit with 2000 larvae of H. a. anatolicum, engorged nymphs were collected, weighed and then cultured in an incubator. A significant decrease in weight of engorged nymphs was only observed in group 1 that immunized with crude extracts of tick’s larvae (P<0.05). Polypeptide profile of the larval and nymphal extracts was analysed by SDS-PAGE, and antigenic pattern with serum of immunized rabbits was evaluated by Dot and Western blot test. The molecular weight of the fraction of larval extract after SDS-PAGE showed six polypeptide bands as follows: 97, 84, 66, 55, 45 and 36 kDa, and in nymphal extract 13 polypeptide bands of 205, 116, 97, 84, 66, 55, 45, 36, 29, 24 and 20 kDa and two bands between 116 and 205 kDa were found. In Western blotting, positive reaction was only observed with sera of group 1 in the bands with 97, 84 and 66 kDa. It seems that the larval extract of H. a. anatolicum can be used as a source of biological material for isolation of protective antigen.

The chemical composition, in situ rumen degradability coefficients of dry matter (DM) and crude protein (CP), in vitro gas production and in vivo digestibility were evaluated for olive cake (OC) silage treated (DM basis) with different additives as follows: (1) untreated OC; (2) OC, 8% molasses and 0.4% formic acid and (3) OC, 8% molasses, 0.4% formic acid and 0.5% urea. After addition of the additives, materials were ensiled for 60 days in plastic bags. The addition of molasses, formic acid and urea resulted in higher DM, CP, pH and NH3-N content. There were some reductions in neutral detergent fiber, acid detergent lignin and acid detergent fiber contents of silages especially with treatment 3. The additives increased the nutritive value and preserved well the ensiled OC. Ruminal maximum potential degradability (a+b), and effective degradability (ED) of DM and CP were higher for treatment 3. Total gas production was higher (P<0.05) for treatments 2 and 3 and was associated with increased (P<0.05) in vitro organic matter digestibility and a non-significant increase in metabolizable energy content. Only CP digestibility was affected by treatments and was highest for treatment 3. In vitro dry matter and organic matter digestibilities improved with treatments 2 and 3. The results indicated that, treating OC (DM basis) before ensiling with molasses (8%), formic acid (0.4%) and urea (0.5%) resulted in a satisfactory and economical source of a non-conventional feed for ruminants.

The technique of intraosseous (IO) infusion has been reemerged as an alternative route of intravascular access for the delivery of fluids and some medications. Complications of IO infusion occur rarely and include fractures and osteomyelitis after long-term use of IO access. The purpose of this study was to compare the efficiency of induction of anaesthesia by a standard intravenous route and an intraosseous route. Ten healthy rabbits were assigned to one of two treatments: thiopental 20 mg/kg administered intravenously via marginal vein of ear and thiopental 20 mg/kg administered intraosseously into the bone marrow of proximal tibia. In each rabbit, the heart and respiratory rates and palpebral, corneal, pinch and withdrawal reflexes were recorded before and every 2 min, for 34 min after induction of anaesthesia. Neither the clinical parameters nor the reflexes showed any significant difference (P>0.05) between the treatment groups. In addition, no adverse reaction was seen in rabbits anaesthetized by intraosseous access. The results of this study showed that the intraosseous injection of thiopental is a rapid, simple, safe and effective alternative option for induction of general anaesthesia in rabbits.

Most highly pathogenic avian influenza viruses (AIV) emerge after field passage of non-pathogenic AIVs in birds. The outbreak of low-pathogenic H7N1 avian influenza virus in Italy during 1999-2000 followed by outbreak of highly pathogenic H7N1 avian influenza virus is one example in this regard. This experiment has been designed to investigate the effect of pre-infection of birds with LPAI on subsequent challenge with HPAI virus from the same outbreak. Chickens were inoculated intranasally with LP H7N1 A/CK/Italy/1279/99 avian influenza virus at 3 weeks of age and two groups of 10 birds were challenged at 18 and 24 weeks of age with homologous HP H7N1 A/ostrich/Italy/984/00 virus from the same outbreak. The overall mortality of birds was 60%; pre-infected challenged birds died 4-17 days post challenge (PC), while naive birds died 2 days PC. Pre-infected birds showed peritonitis, salpingitis and oophoritis in necropsy and histopathology showed very severe necrosis of the spleen, pancreas, moderate to severe necrosis of the liver and inconsistent degeneration and inflammation of the lung. Necropsy of the control bird showed petechial haemorrhage on the heart, caecal tonsils and the tracheal mucosa.

Pasteurella multocida is known as an important heterogenic bacterial agent causes some severe diseases such as fowl cholera in poultry and haemorrhagic septicaemia in cattle and buffalo. A polymerase chain reaction (PCR) assay was developed using primers derived from conserved part of 16S-23S rRNA gene. The PCR amplified a fragment size of 0.7 kb using DNA from nine avian P. multocida isolates. Sequence alignment of the 16S-23S rRNA genes (ITS) revealed a considerable heterogenicity among the isolates. The percentage of similarity varied from 83.3 to 100% among the isolates. An interesting finding from this study was the presence of an inserted sequence (seven nucleotides) in the 16S-23S rRNA region in 55% of the isolates. According to phylogenic analysis based on ITS sequence alignment, the P. multocida isolates classified into 2 distinct clusters. The virulence of isolates in cluster II were higher than those in cluster I. Ribotyping of P. multocida by using 16S-23S rRNA gene PCR sequencing could be used as a marker in epidemiologic studies.

Avian leukosis viruses (ALVS) cause different types of tumours in poultry and can affect the health and egg production of the birds. To investigate the presence of the virus in chicken layer flocks in Shiraz, 222 egg albumen from local layer breeder (25 eggs), local layer grand parent (30 eggs), broiler breeder (60 eggs), commercial layer (46 eggs) and broiler grand parent (61 eggs) were tested by antigen-capture enzyme-linked immunosorbent assay (AC-ELISA). The results showed that 3.33, 76 and 80% of commercial broiler breeder, local layer breeder and local layer grand parent were positive, respectively. Thirty-five albumen samples were randomly selected and tested by RT-PCR using PU1/PU2 and PA1/PA2 primer sets. The samples with ELISA S/P ratio equal or more than 0.17 were positive by RT-PCR using PA1/PA2 primers. This is the first report of the presence of the ALV in egg albumen samples of chicken layer flocks in Shiraz.

The length and structure of the transitional zone in the tunica media in the renal artery of adult male cats were investigated. In addition, the volume of the lumen and different layers in transitional and non-transitional zones in the right and left sides were also determined. Morphometrical, histological and stereological studies were performed on 16 renal arteries of 8 adult male cats. After perfusion and morphometrical measurement, routine tissue processing was carried out by autotechnicon. The processed tissues were embedded in paraffin and sectioned serially into 5 μm thickness. The sections were stained with haematoxylin and eosin and orcein. In the morphometrical measurement, the right renal arteries were longer than the left ones with a mean value of 22.0 ± 0.2 and 18.8± 0.1 mm, respectively. Despite the fact that the right renal artery is commonly longer, the length of transitional zone was 7 mm in both renal arteries of adult male cats. The artery has a structure between muscular and elastic type at its origin with several elastic layers in the tunica media which is gradually changed to a muscular type at the distal section after 7 mm from origin of aorta. Transitional zone has an arrangement of parallel elastic fibers which become rare and fragmented towards the non-transitional zone. The volume of tunica intima, tunica media, tunica adventitia and lumen of the artery decrease from transitional zone towards the non-transitional zone and the volume of these areas in both transitional and non-transitional zones in the right renal artery is more than the left one. The volume of the lumen in transitional zone differs significantly compared to non-transitional zone, in both sides (P<0.05). Also there is a significant difference in the volume of the lumen in non-transitional zone between right and left renal arteries (P<0.05).

In the present investigation a total of six parasite species, some eye-specific and others non-organ specific parasites were found in the eyes of 48 examined fish species, collected from fresh and brackish waters of Iran during 2004-2006. Ichthyophthirius multifiliis was isolated from the external surface of the eyes of Oncorhynchus mykiss, Gyrodactylus stankovici from Cyprinus carpio and Lernaea cyprinacea from Cyprinus carpio and Hypophthalmichthys molitrix. In the vitreous humor parasite species were Tylodelphys clavata (metacercaria) observed in H. molitrix, Alburnus alburnus, Carassius auratus, Cyprinus carpio, Chondrostoma regium, Ctenopharyngodon idella and Capoeta capoeta, and Ornithodiplostomum sp. (metacercaria) in Aphanius vladykovi. Diplostomum spathaceum (metacercaria) was found in the lens of eyes of 40 out of 48 fish species. Among parasite species identified, Tylodelphys clavata and Ornithodiplostomum sp. are recorded in Iran for the first time. Additionally, the geographical distribution and host range of Diplostomum spathaceum metacercaria is also presented in this study.

Prochymosin is one of the most important aspartic proteinases used as a milk-clotting enzyme in cheese production. In the present investigation we report sequence of cDNA encoding goat (Capra hircus) preprochymosin and compare its nucleotide and deduced amino acid sequences with sequences of other ruminants preprochymosin. As bovine prochymosin, the caprine prochymosin cDNA encodes 365 amino acids with a prosegment of 42 amino acids and the mature goat chymosin begins with glycine. The preprochymosin nucleotide sequence reported in this study differs from other reported goat sequence (AY389343) in three nucleotides, two of which alter the amino acids at positions 19p and 139.

Six mixed-breed apparently healthy dogs were intravenously administered a single dose of tetracycline hydrochloride (50 mg/kg) to evaluate the pharmacokinetic parameters of the drug. Blood samples were collected before and at various time intervals after the administration of the drug. Serum tetracycline concentrations were determined over a 24 h period using fluorescence spectrophotometry. Non-compartmental analysis of the data indicated that tetracycline has a half-life of 4.4 h, a body clearance of around 0.7 ml/kg.min and a volume of distribution of about 0.3 L/kg. The pharmacokinetics of tetracycline found in this study is favourable for therapeutic use in the dog.

An outbreak of a lethal disease was reported in 4–6-month-old Holstein calves in a feedlot around Tehran. The signs of central nervous system and gastrointestinal system (GI) involvement were observed in the diseased animals. Necropsy samples of GI, liver, kidney, spleen and lung from 3 died animals were prepared for histopathological examination. Blood and formalin-fixed ear notch samples of 6 calves were submitted for RT-PCR, antigen-capture ELISA (ACE) and immunohistochemistry (IHC) for the detection of BVDV. The results of ACE on buffy coats were negative but RT-PCR of all 6 cases and IHC of 4 cases were positive for BVDV infection. Based on the clinical signs and pathological findings in the GI system and brain, we strongly suggest that the BVDV may represent a gastro-neuropathogen strain. To the best of our knowledge, this is the first outbreak of gastro-neuropathogenic BVDV infection in Iran, which may be acquired postnatally.

This study was undertaken to determine the prevalence and diversity of Eimeria species in sheep in Tabriz suburb. The prevalence of ovine parasitism due to Eimeria spp. was estimated in 240 sheep aged less than six months to over 12 months, in a period of one year (2003-2004). The samples were collected from pre-slaughtered sheep in Tabriz slaughterhouse and transferred to the parasitology laboratory. Afterwards, sporulation of the oocysts was performed. The overall prevalence of Eimeria infection in sheep was found to be 16.7%. Two pathogenic species of Eimeria, including E. ahsata (8%) and E. ovina (18%) and four non-pathogenic species, E. faurei (18%), E. parva (13%), E. pallida (8%) and E. intricata (35%) were identified. All of the infected sheep (40 out of 240) had mixed infections at least with three species. Intensity of the infection was significantly higher in young sheep compared with older animals (P<0.05). Gender had a significant effect on the prevalence and intensity of the infection (P<0.05). Diversity in Eimeria spp. in different age groups, potentially, might be an important factor contributing to notable losses in small ruminants in this area.

Skin lesions were found in two 3–4-year-old Holstein cows in a dairy farm in Shiraz. Lesions were distributed mostly around the neck, forelimbs, hindlimbs, and bilateral of midline portion and varied from nodule-like structure to patch with extensive accumulation of crust. Skin scraping samples were taken from each animal and direct smears were prepared, stained with Giemsa and observed under a light microscope. Some scabs were cultured and incubated both aerobically and anaerobically. Cultured smears were Gram stained and the morphology of isolates were studied. The diagnosis of dermatophilosis was made on the basis of clinical signs, skin lesions and morphological characteristics of the isolates. In this study, the infection could be related to insect population density during the outbreak and exposure to ticks which were observed in the animal environment. Rain scald in the region, especially in the late August and September could be a predisposing factor for flare-up of the infection. This is the first report of dermatophilosis in cattle in Shiraz, southern Iran.

Two male dogs at the age of 3 and 5 months of Doberman pinscher and German shepherd breeds were referred to the Veterinary Hospital of Ahvaz University with clinical signs of depression, vomiting, haemorrhagic diarrhoea, profound dehydration, fever and anorexia. The affected dogs had not the history of vaccination. Concurrent infection of canine parvovirus and coronavirus was detected in dogs by means of immunochromatography assay. The haemogram showed lowered white blood cell counts as leukopenia, neutropenia and lymphopenia. The dogs received supportive treatment to correct the life-threatening dehydration and prevention of secondary bacterial infections. Despite treatment, one dog (Doberman pinscher) died within 3 days after the onset of clinical signs, and the second dog recovered after 4 days. To the best of our knowledge, this is the first report of concurrent infection of canine parvovirus and coronavirus in diarrhoeic dogs in Iran.

A 7-year-old castrated male German shepherd dog was presented with a 10-day history of intermittent lethargy, weakness and episodic seizures. Laboratory findings after admission revealed hypoglycaemia and hyperinsulinaemia. Provisional diagnosis of insulinoma was made based on the presence of concurrent hypoglycaemia and elevated insulin level. In exploratory laparotomy a small nodular mass was detected on the pancreas. Other abdominal organs were normal in gross inspection. The mass was removed surgically. Histopathology of the excised pancreatic nodule confirmed the diagnosis of insulinoma. The dog became seizure free following the surgical operation.

A 5-year-old male cross-bred guard dog with signs of anorexia, vomiting and jaundice was referred to Small Animal Hospital, Faculty of Veterinary Medicine, University of Tehran. Initial diagnostic laboratory tests revealed leukocytosis, thrombocytopenia, haemoconcentration, azotaemia, high liver enzyme activities, proteinuria and bilirubinuria. Aggressive therapeutic procedures failed to improve the animal deteriorated condition and finally the animal died. After necropsy, specimens were collected for microscopic examination as part of completing diagnostic procedures. Results of urine bacterial culture confirmed leptospirosis as a causative agent. Furthermore, numerous large spiral bacteria were also observed under dark-field microscope. This article summarizes and characterizes the historical and physical findings, laboratory data, bacterial culture and pathological diagnostic features of leptospirosis in the cross-bred dog. Based on published data, this is the first case of confirmed Leptospira isolation from a dog in Iran.

The present investigation was performed to determine the effect of long-term administration of sodium selenite on the biochemical indices and concentration of thyroid hormones in calves. Sodium selenite solution was drenched at 0.1 and 0.25 mg per kg body weight for 12 weeks. Higher dose produced characteristic symptoms of selenosis whereas mild symptoms were observed with lower dose. The toxic symptoms appeared when blood selenium level was 1.68 ± 0.13 mg per ml. There was a significant (P<0.05) increase in the activities of the aspartate aminotransferase, alkaline phosphatase, blood urea nitrogen and creatinine levels in the treated animals. The repeated administration of sodium selenite resulted in a significant p-value decline in thyroxine levels on the 10th week and increase in triiodothyronine on the 8th week of treatment. The findings of the present study suggested that sodium selenite induced selenosis alters thyroid hormone levels in plasma.