IRANIAN JOURNAL OF VETERINARY RESEARCH (IJVR)
Year:2001 | Volume:2 | Issue:2|Papers Count:17

In this study, the vertical and transverse diameters of the spinal cord segments and ependymal canal and the ratio between gray matter and white matter in various segments (C1, C4, C8, T4, T7, T13, L4, L7, S2, Co1) of mid-stage fetus, late stage fetus, newborn, 6month old and adult (each on male cat) were measured by standard micrometric method using 5mm thick sections in light microscope.In fetal stage towards adult age, the ratio of gray matter to white matter and the vertical dimeter of ependymal canal were reduced but other measured diameters were increased. Statistically, there were significant differences between parameters, which were measured.

Five Bakhtiari rams aged 6 monthes, with average body weight of 30 kg were used. These rams were looked after for two weeks because of confidence from their health. In this period, they received anthelmintic drug (Albendazole). Blood and cerebrospinal fluid (CSF) samples were collected as blanks fromjugular vein and lumbosacral puncture, respectively.Water drinking was prevented 12 hours before induction of the poisoning until taking the last sample from them. For induction of subacute poisoning, 2.5 lit of 5% saline water was infused by stomach tube through the stomach. In the time intervals 000, 60, 90, 120, 150and 180minutes after the induction of poisoning, blood samples were taken from animals. After the last sampling, a CSF sample was also taken from each of them.The concentration of sodium, potassium, magnesium, chloride and phosphorus were measured in all samples and the results were analysed by statistical methods.The results indicated that sodium and chloride concentrations in serum increased significantly after the poisoning but potassium, calcium, magnesium and phosphorus concentrations in serum decreased significantly (P<0.05).The results also showed that, the change of electrolytes concentrations in CSF was similar to that in the serum. This similarity seems to be due to relationship between the concentrations of electrolytes in serum and CSF.

Some morphometrical parameters of the different segments of aorta were studied quantitatively in three age groups: neonate, sexual maturity and old age of male guinea pig. Immediately following euthanization, the whole aorta was collected and separated into the ascending aorta, aortic arch, cranial and caudal thoracic aortae, cranial, middle and caudal abdominal aortae segments. After fixation in 10% buffered formalin solution, the aortic segments were embedded in paraffin, and histological sections were made from each segment. The sections were stained with H&E and green masson trichrome. It was observed that the widest aortic diameter, lumen diameter and the thickest wall of the aorta occur in ascending aorta. The percentage of the tunica interna and externa, as compared with the total wall thickness was increased gradually from the ascending aorta to the caudal abdominal aorta, whereas the tunica media was decreased. Aortic diameter, lumen diameter, wall thickness and the thickness of tunica interna and media were decreased from the ascending aorta to the caudal abdominal aorta, on the other hand the thickness of the tunica externa was increased.

The patterns, amplitudes and durations of wave in the 152 Turkrnan horses measured using the equine 12 standard leads I, II, III, aVR, aVL, aVF, V10, CV6LU, CV6LL, CV6RU, CV6RL and BA. The electrical axes of T wave in the frontal, transverse and left saggital planes determined by the amplitudes of the wave in the semiorthogonalleads I and aVF, 1 and VIO, aVF and VIO. The amplitudes of the T wave varied between (-) 0.320 mV in the lead CV6RL to (-) 2.490 mV in the lead BA. The durations ranged between 0.040 sec. in the leads I, V10, CV6RU and CV6RL to 0.180 sec. in the leads II, aVF, CV6LL and BA. There were a high accordance between the T wave and QRS complex directions in the two mirror image leads V10 and BA of the Turkman horses. About 70 percent of the T wave vectors in the frontal plane were distributed in the range of 0 to 180 degrees.

Ninety, day old broiler chicks were randomly divided to three groups including: 1- Intact 2- Sham-operated 3- Caecectomised. When the chicks were 6 days old, the caeca of the chicks in group 3 were surgically removed, and in the sham-operated group, an incision was perfomed on the abdomen of chicks and after little manipulation of intestine, the incision was sutured. The chicks of all groups were reared in the same condition and fed by formulated diets for 49 days. The body weight and feed consumption of the chickens was measured when they were 6(prior to the surgery), 8, 14, 21, 28, 35, 42 and 49 days old. The mean body weight of sham and caecectomised groups, up to day 21 and 35 of their age were significantly lower to the intact group, respectively (P<0.05). But after these ages till the end of rearing period no significant difference was observed between body weight means of the three groups (P>0.05). At the end of every week in rearing period, there was no significant difference between feed consumption and feed conversion ratio in the three groups(P>0.05).According to the results of this study it can be concluded that in the broiler chickens fed by adequate protein and low fiber diet, caeca has no influence on body weight gain and-feed' conversion ratio.

Following subcutaneous injection of oil emulsified Newcastle disease vaccine, about 400 out of 40000 chicks in a 5 weeks old broiler breeder farm showed severe local reactions at posterior part of their neck, head and face. One week before, all of the chicks of this farm were subcutaneously injected with an oil-emulsified Newcastle disease vaccine in posterior part of their neck. Postmortem examination of the affected chicks revealed thickening and hardening of subcutaneous tissues of the affected areas. In addition, many white to grayish foci about few mm up to 1 cm in diameter were seen in subcutaneous tissues of the neck. In histopathological sections,. granulomatous dermatitis and granulomatous myositis were diagnosed at the site of injection. Granulomas had typical structure consisted of central cystic cavity and debris of necrotic cells that were surrounded by giant cells with numerous nuclei. Around these lesions, myxomatous connective tissue and mononuclear inflammatory cells including macrophages, lymphocytes, plasma cells and few heterophils were present. Cysts with inflammatory reactions, scattered giant cells and fibroplasia were observed in the tissues between granulomas. Special staining such as Periodic-acid-schiff and Brown-brenn gram stain of the histologic sections did not show any fungior bacteria. These lesions were disappeared after 3, weeks without any treatment and thus it is presumed that these lesions might be postvaccinal allergic reactions due to oil adjuvants of vaccine.

To investigate the helminths and coccidial infections of dairy cattle around Urmia, the faecal samples from 200 cattle and 100 calves were collected and examined. The results indicated that the cadle was infected to Nematode spp (41.5%), Trichuris spp (1%), Dicrocelium dendriticum (1%), Moniezia benedeni eggs(3.5%) and Eimeria spp oocyst (36%) and calves were infected to Nematode spp (23%)and Eimeria spp oocyst(27%).

Serological screening of chicken’s sera for the presence of H9N2 subtype of avian influenza virus (AIV) specific antibodies in Iran is currently carried out by haemagglutination inhibition (ID) test in avian diagnostic laboratories. Therefore, there is a need to prepare an inactivated H9N2 antigen for routine and large scale epidemiological surveillance and control of H9N2 outbreaks. Three non-pathogenic H9N2 AIV strains, isolated during the initial avian influenza (AI) outbreak, were primerely selected to compare their growth in embryonated chicken eggs. A H9N2 AIV isolate designatedas A/chicken/Iran/ZMT-101/98 was provided high yeiled amnioallantoic fluid (AAF) with an average of 10.5 haemagglutination(HA), 109.9 EL050 titers and 3.2 days (77h) MOT, as compared with two other homologous strains. The results obtained indicated that 0.1 percent formalin achieve complete virus inactivation with low destroying effect on HA and HI titers. This antigen was able to detect specific antibody as early as 6 days after post inoculation in HI test, indicating that HI is a reliable, specific and rapid srological test. Comparison of HI and ELISA tests to detect H9N2 infection in the sera obtained during 2 and 4 wks after acute phase of disease showed respectively 94.44 and 98.61 percent similarity. Overall, it is suggested that inactivated H9N2 antigen could successfully be use by avian diagnostic laboratories for routine flocks monitoring and regulatory surveillance of poultry industry.

An investigation was undertaken in order to study the vascular supply and unary collecting system of sheep kidney. Thirteen mature sheep normal kidneys were collected from Urmia slaughterhouse. These organs were subjected to injection of latex through renal arteries and injection of mica through ureters. In this way the casts were made. The results showed that renal artery before entering to the kidney through the hilus was divided into dorsal and ventral branches without any connection to each other. The dorsal branch passed above the renal pelvis and ventral branch passed below the renal pelvis, then with many bifurcations distributed throough the whole kidney. In kidney which mica was injected, the position of renal pelvis and way which ureter leave the hilus ware clearly demonstrated. The average amount of mica injected was 6-8 ml per kidney, which shows the pelvis capacity in sheep. In those kidneys which mica and latex were injected, the position of pelvis and bifurcation of the renal artery were evident.

Bovine theileriosis caused by Theileria annulata is a dangerous and important disease in tropical and subtropical areas. There are large economical losses in these areas every year including in Iran. The vector of the disease, the tick of Hyalomma is found in most parts of Iran. The prevalence of the disease correlates with aboundance of the vector in spring and summer. In this study, prevalence of the disease in terms of month of the year, age, sex and breed of the animal were studied, during the first 6 months of the year 1377.The results showed that in spite of all the means of prevention and vaccination, the diseasehas been known as the most important disease in the region. In relation to the month, the maximum and minimum prevalence of disease was in Khordad and Farvardin, respectively. In relation to age, 76.2 percent of infected cattle were one month old or younger. In relation to the breed, infection of Holeshti.ne, cross breed and native were 1.6, 94.4 and 4.0 percent respectively. In relation to sex, infection rate of males were 55.4 percent and female was 44.6 percent. From the aspect of clinical signs, all cattle showed anorexia and enlargement of lymph nodes, and the other signs were in different percentages.In 58% of blood smears the infection rate of RBCs with the intraerythrocytic form of Theileria was less than 10%, in 38% more than 10%and in 4% the results were uncertain due to technical faults in staining.

The aim of this study was to find out the epidemiological status of Borna disease in two limited groups of people in Iran following the previous study of varied prevalence of Borna disease virus (BDV) infection in horses of Iran (Bahmani et al., 1996).Thirty blood samples were collected from healthy people selected among the people who had contact with apparently healthy horses, but carriers of BDV for many years. These people were called group "A" Thirty blood samples were also collected from the volunteer blood donors of National Blood Transfusion Organization of Iran. These healthy people were called group "B". All volunteers in group A were male except one female. All volunteers in group "B" were male.Total cellular RNA was extracted from peripheral blood mononuclear cells (PBMC) of the above mentioned blood samples. The extracted RNA was amplified and transcribed to cDNA by a nested reverse transcriptase polymerase chain reaction (RT-PCR) to obtain a fragment of the p24 coding region which is relatively conserved within the BDV-RNA genome. Using specific Marker in agarose gel electrophoresis technique, the positive protein bands could be visualized at 391 base pair molecular weight when were caused to shine by ultra violet light in the gel-agar, conjugated with ethydium bromide.The molecular weight of BDV-p24 KDa at 391 base pair could be identified when it was compared with the Marker band (fi-X-174 Hae-III) which was applied in the test. An MDCK (Medin Darby canine kidney) cell persistently infected with BDV was used as positive control and distilled water was used as negative control in each of the serial tests in gel electrophoresis technique.The results were confirmed by Southern blot hybridizationtest using nucleic acid transfer membrane and conjugated oligo nucleotide cDNA with [32 P]- ATP radio isotope. The PBMCs in the people of group "A" showed 26.66% positive reactions for BDV-p24 genome while the people in group "B" showed 13.33% same positive reactions. This significant difference between exposed and nonexposed people to the positive equine reservoirs may imply the possible role of contact contamination in the epidemiology of BDV in Iran. Conducting Western immune blotting technique on the same serum samples indicated the presence of serum antibody against BDV-p24 KDa protein in 23.33% in group "A", while the same positive reaction was 6.66% in group "B". The antibody against BDV-p40 Kda protein was detected in 46% of the people in group "A", while the same positive reaction was 6.66% of the people in group "B".

The introduction of bovine viral diarrhoea virus (BVDV) is a special concern for in vitro production of cattle embryos. Two experiments were designed to evaluate the fertilizability of bovine oocytes exposed to BVDV either at the time of oocyte maturation (Exp.I) or at the time of oocyte insemination (Exp.II). The virus inoculums used was derived nom a persistently infected cow. In expo I, follicular oocytes (n=312) recovered from slaughterhouse derived ovaries were divided into either a control group (n=151) which did not become exposed to BVDV and a treatment group (n=161) which was exposed to BVDV (4 to 4.4 log10 TCID50/50ml) at the time of commencement of in vitro maturation. Results of exp.I showed no significant differences between the control and BVDV exposed oocytes in either the cumulus cell expansion rate (79vs 74%; p>0.05) or fertilisation rate (73.7vs 74.5%; P>0.05), respectively. In expo11, in vitro matured oocytes (607) were inseminated either in the absence (control; n=301) or in the presence of BVDV (4 to 4.6 log10 TCID50/50ml n=306). A significant (P<0.05) reduction in the number of fertilized oocytes with two well formed male and female pronuclei was observed in the treatment group compared to the control group (58vs 73%; P<0.05), respectively .This study demonstrates that bovine viral diarrhoea virus has a significant detrimental effect on the formation of male pronuclei during in vitro fertilization of bovine oocytes.