IRANIAN JOURNAL OF VETERINARY RESEARCH (IJVR)
Year:2006 | Volume:7 | Issue:3 (16)|Papers Count:16

The effect of tamoxifen citrate on bone mass in immobilization osteoporosis was studied in 10 dogs. Osteoporosis was induced by fiberglass cast immobilization of the right hind-limb for 28 days, while the left hind-limb served as a non-immobilized control. Five dogs received tamoxifen citrate (1.5 mg/kg per os) once daily for 28 days; five dogs received no treatment. All dogs were euthanized on day 28 and tibiae were harvested. Bone biomechanical properties and microscopic structures of tibiae from casted and uncasted limbs were studied. Significant differences in the percent of decreased values of examined mechanical properties were found between untreated and tamoxifen-treated dogs. No remarkable histopathological changes indicative of osteoporosis were detected in the tibiae of casted limb of tamoxifen-treated dogs. These findings indicated that short term tamoxifen therapy may have promising effects on prevention of osteoporosis in dog.    

There are increasing evidences that show many xenobiotic chemicals (called as endocrine disruptor chemicals EDCs) through interfering with endocrine system, have the capability to induce developmental and reproductive abnormalities in humans and animals. The yolk protein precursor vitellogenin (VTG) has proved to be a simple and sensitive biomarker for assessing exposure of fish to EDCs especially the estrogenic compounds. Work is ongoing to develop screening and testing programmes for endocrine disrupting effects of new chemicals, and in the focus of this development are the fish test species common carp (Cyprinous carpio). In this study we have developed quantitative enzyme-linked immunosorbent assays (ELISA) for VTG in common carp. The working range of the ELISA was 11.25 to 2,000 ng/ml (25-75% specific binding/maximum antibody binding [B/B0]) with a 50% B/B0 intra- and interassay variation of 3.9% (n = 10) and 12.5% (n = 30), respectively. This ELISA is capable of detecting VTG as low as 6 ng/ml, and can accurately detect VTG in even 10 ml of plasma. The ELISA was applied to measurement of VTG production by male carp (Cyprinous carpio, Cyprinidae) fish exposed to ethynylestradiol. The results showed that the amount of VTG produced in plasma of exposed fish increased in logarithmic order comparing to the control group and the ELISA described here could be used as an indicator of water pollution to estrogenic pollutants.    

Exsheathing fluid (EF) and excretory-secretory products (ES) of infective third-stage cultured larvae of Ostertagia circumcincta were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Five and seven predominant proteins were found in the EF and ES products, respectively. Immunoblotting by sheep pre-infection serum did not react with any of the EF and ES proteins, but the post-infection serum recognized four proteins of 44.5, 41.5, 38 and 24 kDa of the ES products. None of the EF products was recognized by the post-infection serum. Protectivity of the four proteins remains to be determined.    

No published information are available on the reproductive indices of local Abadeh does reared in northern Fars province, southern Iran. This study was conducted to determine the duration of the breeding season, and the length and duration of the oestrous cycle. Twenty single parity 2-year-old does from Abadeh (weighing 19–26 kg) were purchased and transferred to the School of Veterinary Medicine of University of Shiraz. They had access to alfalfa hay, water ad libitum and natural light. Vasectomised teaser buck was turned with the flock and observation was made every 12 hrs during the day for standing heat detection, from late-August (2003) to late-August (2004). To determine the onset of reproductive activity as well as occurrence of silent oestrus, blood samples were collected from jugular vein every 10 days. Following the onset of breeding season and observation of standing heat, 10 does were randomly selected in their 2nd oestrous cycle for twice weekly blood sampling. Serum progesterone concentration was determined using a commercial radioimmunoassay kit. It was found that silent oestrus occurs mostly in early breeding season. The first standing heat was observed in mid-September which was considered as the onset of breeding season. Occurrence of standing oestrus increased through October, November and December. The peak of standing oestrus was recorded during late-October to early, mid-November. The mean ± SD duration of the oestrous cycle was 19.7 ± 1.1 days and the mean ± SD length of oestrus was 23.8 ± 12.3 hrs. The mean (±SD) concentrations of serum progesterone in days 0 (day of standing heat) to 4, varied between 0.1 and 0.8 ng/ml. Concentrations of progesterone during the luteal phase varied between 2.7 and 3.9 ng/ml. The results of progesterone assay during oestrous cycle indicate that the follicular and luteal phases last about 4–5 days and 14 days, respectively. In conclusion, oestrus activity in local Abadeh does is highly seasonal with a peak of activity being observed during the late-October to the end of November.

An experiment was conducted on 400 broilers to evaluate the effects of dietary supplementation of antibiotic and probiotic on performance of birds under heat stress condition. The first group of chickens, the control group, received a diet without any antibiotic and ‍probiotic. The second group received diet with 0.02% virginiamycin antibiotic; the two other groups were fed diets with 0.05% and 0.1% Bioplus 2B probiotic, respectively. The addition of antibiotic to the diet significantly improved body weight gain during 0–3 and 4–6 weeks (heat stress) periods as compared to the control and 0.05% probiotic-supplemented groups (P<0.05). Feed intake of different groups did not differ significantly (P>0.05). Addition of antibiotic or various levels of probiotic to the diet significantly improved feed conversion ratio during 4–6 weeks (heat stress) period as compared to the control group (P<0.05). Supplementation of diet with antibiotic had no significant effect on antibody production against sheep red blood cells (SRBC), Newcastle disease virus (NDV) vaccine, white blood cell (WBC) count, heterophil to lymphocyte ratio (H/L), serum cholesterol and haemoglobin content (P>0.05). Supplementation of diet with various levels of probiotic had no significant effect on antibody titer against SRBC, NDV vaccine and haemoglobin content (P>0.05). However, supplementation of diet with 0.1% probiotic significantly increased WBC count and decreased H/L as compared to the control group (P<0.05) which is important in reduction of stress effects on birds.

Oxidative stress has been identified as a crucial factor leading to male infertility largely due to peroxi­dative damage to the sperm cell membrane. Cadmium (Cd) is a widespread environmental pollutant and one of the well-known reproductive toxicants. Because of its long biological half-life (10–30 years), Cd accumulates in the biological systems. The present study was designed to assess the concentration-dependent in vitro effect of 20 to 700 µM of Cd on the membrane integrity, motility, and acrosomal status of Holstein bull spermatozoa. We recorded a significant elevation in the malondialdehyde (MDA) level, increased lipid peroxidation (LPO) rate and a drastic decrease in the spermatocrit values, especially at the 700 µM concentration of Cd, indicating deleterious effects of Cd on the intactness of the sperm membrane. There was also a negative correlation between the LPO rate and both the percentage of motile spermatozoa (r = -0.89) and sperm viability (r = -0.86). Performing the gelatin test indicated that Cd altered the integrity of acrosomal membranes and showed an abnormal acrosome reaction. In this regard, a reverse correlation was found between the LPO rate and the percentage of halos (r = -0.96). In conclusion, Cd was proved to be a potential toxicant in the category of environmental factors that induced membrane impairments, lowered motility and viability, and decreased rate of acrosome reactions leading to bull sperm dysfunction.

Sixteen avian influenza (AI) H9N2 viruses were isolated from disease outbreaks in different parts of Iran during (1998–2001). These AI isolates were used for pathogenicity, haemagglutinin (HA) gene variation and phylogenetic analysis. Results in both pathogenicity tests and HA gene cleavage site sequence detection represented a non-highly pathogenic feature for all Iranian AI isolates studied. The cleavage site motif (R-S-S-R) of all AI isolates however, indicated that they had capability of becoming highly pathogenic viruses following 2 nucleotide substitutions at this region. Based on 450 nucleotides region obtained for local isolates and those for referenced viruses available in Gene Bank database used in phylogenetic analysis, all viruses placed on 3 distinct groups, 2 for Iranian and 1 for reference viruses. Among the reference AI viruses, isolates from Pakistan, Saudi Arabia and 1 from Germany showed less difference with Iranian AI isolates. Results also revealed that the circulating viruses in neighbouring provinces have been remained with less mutation for about 2 years.    

The major lymphoid tissues in teleost fish are the kidneys, thymus, spleen and mucosa-associated lymphoid tissue including the skin, gills and intestine. The head of kidney (pronephros) is an important haematopoietic organ and has morphological similarities with the bone marrow in higher vertebrates. In this study, during 12 months from August 2002 to July 2003, 120 grass carp (10 fish/month) were harvested from 3 fish culture ponds in Ahvaz. The water, weather temperatures and light duration of days (photoperiod) were recorded. After biometrical examination of age, weight and the length of the fishes, the whole kidneys were removed from abdominal cavity and samples were fixed in bouin’s solution for light microscopy and in glutaraldehyde for electron microscopy. The results showed that the lymphoid tissue distribution has significant changes during different seasons so that, the mean ± SEM of lymphoid tissue distribution in hot seasons (33.53 ± 0.59 mm2/cm2) was more than cold seasons (19.20 ± 0.65 mm2/cm2). Also the statistical results showed that water temperature has more significant (P<0.05) effect on lymphoid tissue. Degenerated lymphoid cells with pale and vacuolated cytoplasm were observed. A reversed correlation was found between the number of normal and degenerated lymphocytes. Electron microscopy revealed that degenerated lymphocytes were devoid of membranous organelles, their cytoplasms were vacuolated and the nuclear envelope had some alterations.    

Capsules from a range of pathogenic bacteria are the key determinants of virulency. The capsule has been implicated in virulence of Pasteurella multocida. In this study a type-specific polymerase chain reaction (PCR) assay was used for capsular typing of 39 avian P. multocida isolates from Iran. The PCR amplified a fragment of 1044 bp from all of tested isolates. It was found that all avian P. multocida isolates belonged to capsular type A. The sequence alignment of the fragment showed a high similarity (>96%) with the published sequences of P. multocida hya gene in the Gene Bank. It was recognised that P. multocida capsular group A is the dominant cause of fowl cholera in Iran.    

We conducted this study to determine the level of immunity after vaccination of lambs with whole body Echinococcus granulosus. To do so, 200 mature E. granulosus parasites, which were kept in 10% formaline for 8 months, were obtained from the Department of Parasitology, School of Veterinary Medicine, Ferdowsi University of Mashhad. The soluble protein of the parasite was prepared. The sample was homogenized in a blender, sonicated on ice and then centrifugated for 15 min at 10,000 g. Final yield was kept at -20ºC until used. Eight 4–6-month-old lambs of mixed sex, were divided into 2 equal groups; each lamb in the test group was vaccinated subcutaneously in the neck with 2 ml of the vaccine (1 mg of whole body of E. granulosus protein dissolved in 1 ml of PBS plus 1 ml of Freund’s complete adjuvant (FCA)). The control lambs were vaccinated only with adjuvant in PBS. Lambs were re-vaccinated four weeks after the first vaccination with the same preparation except that FCA was replaced by Freund’s incomplete adjuvant (FIA). Three weeks later, each lamb was administered a challenge infection dose of 2000 protoscolices intraperitoneally and 10 adult E. granulosus. After 7 months, all lambs were killed and examined for hydatid cysts. We found two cysts in the liver and and one in the lung of only one of the vaccinated lambs. The number of cysts in vaccinated lambs were significantly lower than that in the control group (P<0.001). This means that the protective immunity in lambs with whole body of E. granulosus was approximately 90%.    

Veterinarians increasingly play a major contributory role in dairy practice and management. With increasing importance of economical pressures, bioenvironmental limits and increasing demand for higher quality products, veterinarians are more involved in nutrition management and advice, both from an economical view of productivity and preventive aspects of veterinary medicine. The concept of food animal production medicine is the hallmark of such a change from purely diagnosis and treating sick cows to design strategies for disease prevention and economical profitability. One of the essential parts of the new role is to have a good command of nutritional concepts and acquaintance with ration formulation procedures and also softwares. It appears that the available ration formulation softwares are insufficient in view of estimating necessary criteria for dairy practitioners. Moreover, the release of new edition of NRC and subsequent modification of software programs for ration formulation always lag behind the generation of new knowledge in dairy nutrition. This article describes the basic nutritional concepts, as well as a practical approach to design a ration evaluation program based on Microsoft® Excel. The program can be designed in a profession-oriented approach.    

Epidemiological studies were undertaken at slaughter-houses, livestock farms, veterinary hospitals and on household buffaloes under climatic conditions of four different districts of Punjab province. Infection rate was 22.29, 28.33, 17.08 and 12.75%, respectively in slaughter-house buffaloes, livestock farm buffaloes, veterinary hospital buffaloes and household buffaloes. Overall the season wise the highest prevalence (28.33%) was recorded in buffaloes at livestock farms followed by slaughtered (22.29%) and veterinary hospital buffaloes (17.08%). While the lowest (12.75%) prevalence was recorded in household buffaloes during spring. It was also observed that the higher infection rate was recorded in younger buffaloes (below two years of age) than older (above two years of age) where as sex wise the prevalence indicated that male buffaloes were more commonly affected than females. Snails belonging to genera Bulinus, Lymnaea and Planorbis were also observed which are responsible for the transmission of paramphistomiasis.    

Definitive diagnosis of brucellosis is made by isolation of the causative agents, which is a time-consuming procedure. To evaluate the efficacy of Dot-ELISA for detecting brucellae in clinical samples, 94 different specimens taken from animal origin were cultured on brucella selective culture media and colonies were identified biochemically. The specimens were also examined after centrifugation by Dot-ELISA using a specific anti-brucella antibody, a suitable peroxidase conjugate and substrate. Of the 94 samples, 5 (5.31%) were positive in Dot-ELISA and 4 (4.25%) had positive cultures. In comparison with culture, the sensitivity and specificity of Dot-ELISA for detection of brucellae in the samples was 80 and 100%, respectively. There was 98.9% agreement between the two tests. The results indicated that Dot-ELISA is a good and rapid test with acceptable sensitivity and specificity for detection of Brucella spp. in aborted fetal stomach contents.    

To determine the prevalence of bacterial mastitis in cattle, milk samples positive for California mastitis test (CMT) were cultured during a period of almost 4 years. The bacterial species isolated from 2904 milk samples studied were coagulase negative Staphylococcus sp. in 879 (30.27%) samples, Streptococcus agalactiae in 642 (22.11%), S. dysgalactiae in 332 (11.43%), E. coli in 295 (10.16%), Staphylococcus aureus in 84 (2.89%), Bacillus cereus in 51 (1.76%), Arcanobacterium pyogenes in 31 (1.07%), Pseudomonas aeruginosa in 6 (0.21%), Klebsiella pneumoniae in 4 (0.14%), Pasteurella multocida in 1 (0.03%) and Mycoplasma sp. in another (0.03%) sample. No growth was found in 578 samples (19.90%). Thirty-one (37%) of 84 animals which were infected with S. aureus, had acute infection. We found that contamination of milk with coagulase negative staphylococci are the most frequent bacterial infection in dairy cattle around Tehran; it mostly causes subacute form of the disease. S. agalactiae, S. dysgalactiae and E. coli are the second, third and the fourth causative agents.  

Newcastle disease is one of the most important diseases of poultry. It usually causes a great loss in poultry industry and domestic village chickens. Since domestic chickens in villages are free ranging for food, the chance of their contact with wild birds that may act as reservoirs is high. To determine the role of domestic chickens in the epizootiology of Newcastle disease virus in villages of Isfahan province, 400 serum samples from chickens with no history of vaccination from four regions (Khomeinishahr, Zarinshahr, Falavarjan and Mobarekeh) were collected in summers of (1998) and (1999). Haemagglutination inhibition (HI) test was used for titration of antibodies against Newcastle disease virus. Chi-square and binomial tests were used for statistical analyses. 69.5 and 68.5% of the sera were positive in the two consecutive seasons (P>0.05). About 25% of 3–4 month- and 1–2-year-old chickens were negative for HI antibodies and thus were sensitive to the disease in each season. Significant correlation was observed between the HI antibody titers and the age of the chickens (P<0.01). A specific pattern of seroconversion was observed which was independent to the prevalence of the disease in industrial poultry flocks in each region and all regions studied. It was concluded that about 35% of the domestic village chickens are protected against virulent strains of Newcastle disease in summer. For protection of the remaining chickens, routine vaccination, especially in spring and summer is suggested.

Herein, we presented the first report on bluetongue (BT) disease in 10 pregnant camels in a herd from Kerman province, Iran. All sera samples were tested serologically (AGID, C-ELISA). We also used the Razi-BK cell line, performed primary culture of ovine kidney and inoculated intravenously the embryonated chicken eggs (ECE) to culture and isolate the BT virus.  Efforts to culture and isolation of BT virus have met with very limited success. Following precipitation test (AGID) and C-ELISA, 5 of 10 sera in AGID test, and all in C-ELISA became positive. Further studies are needed on the ecology of camels and vector midges to clarify the reason for infection of the camels in Iran.