Journal of Veterinary Research
Year:2011 | Volume:66 | Issue:3|Papers Count:19

Endocarditis of cattle can develop as valvular, mural or concurrent involvement of the valvular and mural endocardium. Given the importance of endocarditis among the diseases of the cardiovascular system in cattle, 568 dairy cows were studied through complete clinical examination, looking particularly for special signs of heart involvement. The cows suspected of having a heart problem were labeled following the identification. Additional measures including blood sampling, carcass examination, and lesion sampling for histopathology were carried out in the abattoir, and endocarditis was diagnosed in 2.81% of the cases. The mean age of the cows with endocarditis was 5.4 years. The body temperature was higher than 39°C in 56.2% of the cases. Almost 70% of the cows had more than 84 heart beats per minute. Acardiac systolic murmur was found in 56.2% of the cows. Fewer than 5,500 white blood cells per microliter and neutrophilia with more than 40% neutrophils was diagnosed in 75% and 50% of the cases, respectively. Given these results, it was concluded that despite the absence of audible systolic murmur using a stethoscope, it is probable to see valvular endocarditis, particularly in industrial mid-aged dairy cows with a focal active infective involvement showing mild fever, persistent high or at least relatively high heart beat rate and intensity, marginal leucopenia, and relatively increased neutrophils and monocytes. Therefore it may be suitable to conduct echocardiography due to its very applicable findings.

Cadmium toxicity can cause kidney failure, liver damage and a weakened immune system in experimental and naturally occurring toxicities. This study was designed to investigate the effects of cadmium (Cd) on the histology and the rate of lymphoid apoptosis in the bursa of fabricius of chicken. One-hundred 20-day-old male Ross broilers were purchased and randomly divided into four groups. The control group (C) received no Cd, whereas groups 1, 2, and 3 had rations administered containing 25, 50 and 100 ppm cadmium as CdCl, respectively. At days 14, 28 and 42 seven chicks from each group were randomly selected and sacrificed. The bursa of Fabricius of each chick was removed, weighed, fixed in 10% buffered formalin and processed for histopathology and assessment of the rate of lymphoid cells apoptosis. The apoptotic cells were demonstrated in paraffin embedded tissue sections using the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) method. The concentration of Cd in the liver samples was measured by atomic absorption. Areverse correlation between the levels of Cd in the rations and the body weight of the chickens (p<0.01) was found. The concentration of Cd in the liver showed a positive correlation with the levels of Cd in the rations (p<p0.01). The number of apoptotic lymphoid cells was significantly increased in those groups receiving higher levels of Cd (especially groups 2 and 3) (p<0.01). Morphologically, plicas and lymphoid follicles of groups 2 and 3 were smaller than of the control group. In the histological analysis they were found to be hypocellular and some of them were edematous. Compared to the control group, there was an increase in the number of intraepithelial cysts in groups 2 and 3 at days 28 and 42. In addition, atrophic changes of bursal paranchyma were observed in group 3 after 42 days. It can be concluded that under experimental conditions the higher concentrations of Cd in the rations (50 and 100 ppm) has detrimental effects on the bursa of Fabricius of chickens.

Newborn calves are agammaglobulinemic due to not receiving maternal immunoglobulin (Ig) in the uterus, and gain immunity immediately after birth through colostrum intake. Abomasum produces more acid within 24 hours after birth, leading to an increase of the probability of colostrum globulin destruction. The aim of the present study was to find if blocking acid secretion through proton pump inhibitors might prevent the destruction of colostrum immunoglobulins. Fifteen newly-born male Holstein calves were divided into five equal groups, including three control groups and two test groups. The calves were fed colostrum and milk at zero, 12, 24, 36, 48, 60, 72 and 84 hours after birth using an esophageal tube as follows: Control groups: A-calves were fed milk for 24 hours after birth, then colostrum for 72 hours; B-calves were fed milk for 48 hours after birth, then colostrum for 72 hours; C-calves were fed colostrum for 72 hours after birth. Test groups: A) pantoprazole was injected intravenously every 24 hours (2 mg/kg) and the calves were fed milk for 24 hours after birth and then colostrum for the next 72 hours. B) pantoprazole was injected intravenously every 24 hours (2 mg/kg), and the calves were fed milk for 48 hours after birth and then colostrum for 72 hours. Serum IgG, IgM and IgA levels were measured using ELISA. The results did not show any significant differences in Ig blood concentrations in the control and test groups. Therefore, it is assumed that the high pH of abomasum has no significant effect on Ig intake.

Beluga (Huso huso) is one of the most valuable species of sturgeons and many efforts have been made to artificially reproduce, culture and restore this precious species. The objective of this study was to find the effects of garlic essential oil as an immunostimulant on hematological indices and on the cellular immunity system of juvenile belugas. An experiment was organized in which six different diets were fed to belugas including: diet without garlic essential oil and antibiotic, diet with oxytetracycline antibiotic (30 mg/kg), and four diets with various amounts of garlic essential oil (0.05, 0.10, 0.15 and 0.20 g/kg). Beluga juveniles with an average weight of 24±2 g were fed these diets for 56 days. At the end of the experiment, hematological indices were determined. The blood coagulation time and mean corpuscular hemoglobin (MCH) indices increased in the groups treated with garlic essential oil. Significant increases in lymphocyte counts were observed in groups fed 0.05, 0.10 and 0.15 g/kg garlic essential oil as compared with the antibiotic and control groups. A significant decrease in the blood neutrophil count was observed in the belugas fed 0.15 and 0.20 g/kg garlic essential oil compared with the other treatments. In conclusion, these results showed that adding garlic essential oil increases the blood coagulation time, the hemoglobin content of red blood cells, lymphocyte numbers, and decreases eosinophils. Significant improvements of the immune system and of the physiological condition were observed in juvenile belugas receiving garlic essential oil compared with the control and the antibiotic treatments. It can therefore be used as a suitable replacement for oxytetracycline in the diet of juvenile belugas.

Heat stress causes reduced fertility and significant economic loss in dairy cattle. To override the suppressive effects of heat stress, various hormonal manipulations have been utilized. The aim of this study was to compare the effect of progesterone (in the form of CIDR) and administration of GnRH after insemination on the conception rate of heat stressed dairy cattle. All cows were inseminated at estrus and were then alternately assigned into three groups on day 5 after artificial insemination (AI): i) GnRH group (n=44) received an IM injection of 500 mg GnRH (GONAbreed, PARNEL, Australia,); ii) CIDR group (n=44) received a CIDR (EAZI-BREED, Hamilton, NZ, containing 1/9 g progesterone) which was removed after a week; and iii) control group (n=36), which did not receive any treatment. Conception was diagnosed on day 32-39 after AI by ultrasonography. Conception rate in GnRH, CIDR and control groups were 54.5%, 54.5% and 58.3%, respectively. The results demonstrated that there was no significant difference among the three groups (p>0.05). These treatments had had no statistically different effects on lactation, milk yield, days in milk and number of AI (p>0.05). Conception rates within GnRH and CIDR groups in <150 and >150 days in milk subgroups were 74.4%, 40.7%, 84.6% and 41.9%, respectively and differed statistically significantly (p>0.05). Conception rate within control and CIDR groups among <3 and >3 numbers of AI were 80%, 31.2%, 84.2% and 32%, respectively, which was statistically significant (p>0.05). According to the results of this study, the use of GnRH and CIDR after AI did not improve conception rates of mildly heat stressed dairy cattle.

Verotoxigenic strains of E. coli mostly contain one or both of stx1 and stx2 genes. Both of these genes play a role in pathogenicity of the bacteria. These strains cause bloody diarrhea, uremic haemolytic syndrome and purpura thrombocytopenia. Because of a high probability of the presence of verotoxigenic strains of E. coli in various foods, especially milk and cheese, and due to the importance of these strains to human health, we aimed to determine the presence of verotoxigenic strains of E. coli in unpasteurized milk and cheese by PCR. In this study, 200 samples of raw milk and 80 samples of unpasteurized cheese were collected, and verotoxigenic E. coli were isolated using selective media. PCR was used to determine some virulence genes including stx1, stx2, eaeA and hlyA. Thirty-eight and 14 E. coli samples were isolated from raw milk and unpasteurized cheese, respectively. The isolates were examined by PCR in order to find the O157:H7 specific DNA and stx1, stx2, eae and hlyA genes. Two out of 38 isolates originating from raw milk were typed as O157:H7, both of them containing stx2, eaeA and hlyA genes. Another isolate, which was not O157:H7, also contained the stx2 gene. No isolates possessed the stx1 gene. None of the isolates originating from unpasteurized cheese samples contained any of the virulence genes.

Sexual cells in male fishes are microscopic and smaller than eggs in females. Due to the late maturation age in sturgeons, the biopsy of gonads and histological studies are one of the most important and reliable ways to detect and separate males and females from each other at early ages. The aim of the present study was to determine and divide the sexes in farmed Acipenser persicus reared under artificial conditions. In order to detect and determine sexual maturation stages, gonads of 81 farmed A. persicus were sampled by biopsy. Samples were fixed and studied by light microscope. Results showed that males and females were 30 (37%) and 51 (63%) individuals, respectively. The determination of sexual maturation stages in A. persicus showed that 16% were at stage I, 23.5% at stage I-II, 59.3% at stage II and 1.2% at stage III. The number of females was higher than that of males, but sexually mature females were at lower maturation stages than males in the same age and rearing conditions.

The Caspian miniature horse is one of the rarest small horse breeds in Iran. It is an Iranian breed with a small conformation compared to other breeds. In this study, the coronary arteries of six Caspian miniature horses older than two years were studied. The origin, distribution and possible anastomoses of their branches were noticed. Three excised hearts were convoluted and injected with rodopas resin to obtain arterial casts. The other three hearts were injected with gelatin choromopaque and were subsequently radiographed. The injected hearts and casts were carefully dissected and photographed. This study showed that the pattern of distribution of coronary arteries is almost similar to that of ordinary horses. No anastomoses were observed between branches of the left and right coronary arteries.

Due to the importance of sea cucumbers and the paucity of information about the status of Iranian populations, this study was necessary. Therefore, the biology of the reproduction system and macroscopic and microscopic examinations of the sexual glands of Holothuria leucospilota were carried out in this study. Data were obtained from monthly sampling of H. leucospilota during a one-year period on the Bustaneh Coast of the Persian gulf, Hormozgan, Iran. Atotal of 124 females and 108 males were collected. The gonads were found to be composed of many tubules. The gonad color of males of this species is creamy, while female gonads are pink to reddish-orange. Macroscopic and microscopic features of the gonads were used to assess maturity stages. The studied macroscopic features were gonad color, gonad weight, their length and diameter, and the number of tubules. Microscopic examinations included histological studies of hemotoxylin and eosin (H&E) stained texture slides. Based on these criteria, five stages of maturity were determined for both sexes: early growth (1), growth (2), advanced growth (3), mature (4), and post spawning (5). The tubules were found to be longer and narrower in males than in females. The measured biometric factors of gonadal tubules developed from stage 1 to stage 4 of sexual maturity and declined in stage 5. The relationship between the number of tubules and the gonad weight was also calculated. The coefficient of a diagram was determined as 0.73 for male and 0.80 for female H. leucospilota.

Rumen-protected conjugated linoleic acid (CLA) may increase the protein to fat ratio in milk, and potentially improve the energy balance of early lactation cows. The objective of this study was to evaluate the production performance and blood metabolite changes in Holstein cows supplemented with four different doses of CLA postpartum in early lactation. Eight multiparous Holstein cows with atleast 25 kg/day milk production were randomly chosen and were included in an experimental design with four three week periods (7 days of adaptation and 14 days of treatment and sampling). The experiment was carried out with four levels of protected CLA supplement including 0, 50, 100, and 150 g per day per cow. Blood metabolites such as cholesterol and LDL-C content decreased significantly (p<0.05), but other metabolites such as HDL-C, VLDL-C, triglyceride and BHBA did not change (p>0.05). Milk production increased significantly (p<0.05), and 100 g/day of CLA supplemented treatment resulted in the highest production compared with the other groups. Milk fat percentage of the treated cows was reduced significantly and followed a dose-dependent response. No significant results were observed with regard to the protein content, solids-non-fat and milk density of the milk (p>0.05). The increased milk production, and decreased blood LDL-C and cholesterol levels indicate an improvement in the physiological state of the cows. Given the enrichment of produced milk using this supplement, it is highly recommended to provide these supplements in dairy cow diets.

In this study the effects of Silybum. marianum extract on some immune responses and hematological parameters of the common carp (Cyprinus carpio) were investigated. Atotal of 280 fish weighing 65.12±8.22 g were randomly divided into four equal groups. Group1 was immunized with Aeromonas hydrophila bacteria and fed with a diet containing 0.5% S. marianum extract. Group 2 was non-immunized and fed with a diet containing 0.5% S. marianum. Group 3 was immunized with A. hydrophila and was fed with a S. marianum-free diet. Group 4was neither immunized nor fed with S. marianum. Blood samples were taken every 10 days for 40 days. Sera samples were analysed for lysozyme activity, serum bactericidal activity, alternative complement activity, total protein, IgM concentration and anti-A. hydrophila antibodies. Blood samples were also used for hematological parameters, PCV, Hb, WBC, RBC, MCV, MCH, and MCHC. 30 fish in triplicates were challenged with A. hydrophila. The results showed that the values for WBC, PCV, total protein, IgM levels, and lysozyme activity were significantly increased in the serum of S. marianum-treated fish (p<0.05). No significant differences were recorded in anti-A. hydrophila antibody levels, complement activity, or other hematological parameters in S. marianum-treated fish compared to controls (p>0.05). The RPS and serum bactericidal activity was only increased in the non-immunized, S. marianum-fed group when compared to non-immunized, S. marianumfree group. This study indicates that oral administration of S. marianum enhances some nonspecific immune responses in C. carpio, and therefore it can be recommended as an herbal immunostimulant in fish.

Wool growth is influenced by photoperiodic period of different seasons; under similar nutritional conditions, more wool is produced in longer photoperiodic season. In this study, the effects of photoperiod on fiber and skin follicle characteristics of three sheep breeds were studied. Forty non-pregnant and non-milking ewes (Chios, ArkhaMerino × Moghani and Suffolk × Moghani breeds) with a similar age were selected. Equal numbers from each breed were divided into two groups (20 ewes/group), and the two groups were treated with a natural photoperiod (open natural environment: 12 hours light-12 hours dark) and an artificial photoperiod (8 hours light and 16 hours dark) for 50 days. All animals were fed ad libitum with a similar diet including alfalfa, straw and barley at maintenance level. At the end of the treatment period, 50 g of wool was collected from the left mid side area (about 20 cm from the spinal column on the third rib) by a laboratory wool clipper, and a skin biopsy was taken from the right mid side area using a 1 cm diameter trephine. The following fiber characteristics were measured: staple length, fiber diameter, percentage of medullated and non-medullated fibers, wool efficiency. Analyzed follicle characteristics included follicle type ratio, follicle density, and follicle activity. A randomized design analysis of the data and comparison of means were performed with Duncan's new multiple range test. Results indicated that the primary follicle density in sheep under a natural photoperiod were significantly (p<0.01) lower than under an artificial photoperiod. The secondary to primary follicle ratio in sheep under a natural photoperiod were significantly (p<0.01) higher than in sheep under the artificial photoperiod. The percentage of inactive secondary follicles in sheep under the natural photoperiod were significantly (p<0.05) lower than in sheep treated with the artificial photoperiod. Both natural and artificial photoperiod had no effect on fiber characteristics.

Due to conflicts in the results of previous studies comparing the mental health and personality characteristics of pet owners and non-pet owners, and because of the lack of similar research in the Iranian society, this study was conducted to compare the mental health and personality characteristics of pet owners and non-pet owners. The test group consisted of 400 individuals who referred to the veterinary clinic of the University of Tehran in a 12-month period, and 100 non-pet owners as a control group that were matched based on sex and age with the owners. The International Personality Item Pool (IPIP) and General Mental Health Questionnaire (GHQ-28) were applied for data collection. Data analysis, using multivariate analysis of variance showed that all groups of pet owners were less open to experience than control group members. Furthermore, mental health problems were observed at a higher frequency in pet owners. Therefore, it was concluded that the causes and conditions of pet ownership in the Iranian culture could be different from those in other cultures.