Journal of Veterinary Research
Year:2012 | Volume:67 | Issue:3|Papers Count:18

BACKGROUND: Cryptosporidium is an intracellular protozoan parasite that known as the major cause of diarrhea in human and animals. OBJECTIVES: The level of infection to Cryptosporidiumin diarrheic calves of livestock around Tehran and the role of risk factors on its emergence were studied. METHODS: 200 fecal samples from diarrheic calves of livestock’s around Tehran city were collected by cluster sampling method and were studied by modified Ziehl-Neelsen staining method. RESULTS: Existence of Cryptosporidium infection was confirmed in 18 calves (9%). Incidence rate of the infection did not have any significant relationship with sex of animals (p=0.928) and diarrhea history (p=0.640), but the incidence rate of the infection was more in suckling calves with age of less than 2 months with dry fertilizer bedding. CONCLUSIONS: According to the reports of Cryptosporidium infection in multiple studies from different regions of Iran, recognizing the risk factors on the infection incidence can have an important role in controlling the protozoan.

BACKGROUND: Brucellosis is a zoonotic disease that is widely distributed throughout the developing countries. OBJECTIVES: The status of bovine brucellosis combating program in Iran from beginning to now was reviewed. METHODS: The information of 59 year combating against bovine brucellosis were obtained from Iran Veterinary Organization. RESULTS: Bovine brucellosis was first recognized in 1944 in Iran and is now endemic. In 1949, a bovine brucellosis combating program was setup which included vaccination of female calves with strain S19/RB51, infection diagnostic testing and slaughtering the infected cattle. Prevalence of brucellosis among industrial and semi-industrial dairy cattle calculated as 0.3%. CONCLUSIONS: Controlling and prevention of bovine brucellosis is far more complex than vaccination, testing and slaughtering the infected livestock. A financially well- supported control and eradication program and joint efforts between the farmers and governmental authorities are needed as a mean to prevent the spreading of disease. Without these, even a very good strategy will fail.

BACKGROUND: Electron beam irradiation and using of organic acids cause reducing or eliminating the microbial load of poultry diets. OBJECTIVES: This study was conducted to compare the effect of electron beam irradiation and organic acids on diet microbial load, immune system, serum lipids, intestinal morphology, organs relative weight and growth characters of broilers. METHODS: 300 day-old male broilers (Cobb 500) were randomly divided into 5 experimental groups, so that each group included 4 replicates with 15 birds per pen. Treatments were basal diet as control, irradiate diet by 3, 5 and 7 kGy doses and diet containing Formycin 0.2%. RESULTS: The highest and lowest of daily weight gain average were observed in finisher and total period by 7 kGy and control groups, respectively (p<0.05). Moreover, a significant reduction were observed in microbial load of diets among treatments (p<0.05). Highest (5.66) and lowest (4.17) antibody titer against SRBC were observed in Formycin and control groups, respectively (p<0.05) after 2nd injection. Highest and lowest percentage of breast weight and abdominal fat were observed in 7 kGy and control groups, respectively (p<0.05). Greatest villus height (1089 mm) and villus height to crypt depth ratio (5.84) in jejunum were obtained in 7 kGy group (p<0.05). CONCLUSIONS: Experimental dietary irradiation improves broiler performance, that its trend is more evident with increasing exposure dose.

BACKGROUND: in this experiment, the effect of consecutive oral levamisole usage on cellular and humoral responses of broilers immune system was evaluated. OBJECTIVES: The aim of this experiment was to determine the best level of levamisole for stimulating immune system of broilers. METHODS: The experiment was conducted by 250 day old (male and female) broiler (Ross) chicks with an average live weight of 40.2 g. Effect of zero (control L0), 3.5 (L3.5), 7 (L7), 14 (L14) and 28 (L28) mg/l of levamisole in drinking water from 5 to 25 days under randomized design using a factorial experiment with 5 replication were studied. Cellular immune responses were assayed by PHA-P injection in the skin fold of wings (day 15) and thickness of skin were measured after 24 and 48 hours. Sheep Red Blood Cell (SRBC) 25% were injected in the breast muscle in days 7 and 21 to investigate humoral immune responses, and IgG titer against SRBC was determined in days 7, 14, 28, 35, and 42 by agglutination test. RESULTS: Cellular immune responses to PHA-P in treatments containing 7 and 14 mg/l of levamisole (0.272 and 0.205, respectively) were significantly affected (p<0.05). IgG titer against SRBC in treatment containing 14 mg/l of levamisole (6.16) was significantly higher than other groups (p<0.05). Carcass trait of broiler chicks were not affected by different level of consecutive oral levamisole (p>0.05). CONCULUSIONS: The low level (up to 14 mg/L) of consecutive oral levamisole promotes cellular and humoral immune system responses of broiler chicks.

BACKGROUND: Contagious and environmental bacteria are current causes of mastitis and Bulk Tank Bacteria Count (BTBC). Beside other hygienic procedures related to controlling mastitis, Post-Milking Teat Dipping (PMTD) with a suitable teat antisepsis has a special place and can play an important role in the kind of herd mastitis and decreasing the Total Bacteria Count (TBC). OBJECTIVES: This study was performed to evaluate the efficiency of short-time changing of PMTD solution on count and kind of milk tank bacteria. METHODS: This study was conducted in 2 large dairy farms that their current antisepsis was iodophor components in 4 periods around Tehran during March to August 2010. In each 4 periods after the last time that iodophor was used, milk transfer tank sample was collected and 3 tests include Bulk Tank Somatic Cell Count (BTSCC), milk quality tests and bacterial isolation were performed. Then, antisepsis was replaced with chlore components for at least 2 weeks. At the end, another milk tank sample was obtained and tests were done again. RESULTS: Sectional changing of iodophor with chlore components in all 4 periods, according to decreasing in TBC, Coliform count, preliminary incubation count, laboratory pasteurized count, Staphylococcus count and Streptococcus count caused increasing the quality of milk and decreasing the mastitis. CONCLUSIONS: Changing in post-milking teat dipping has positive effect on quality of raw milk.

BACKGROUND: Fungal agents are considered as one of the most prevalent organisms in external otitis. OBJECTIVES: The aim of this study was to compare the fungal flora of external ear canal and concave surface of auricle in healthy Persian and Domestic Short Hair (DSH) cats. METHODS: Samples were collected from 120 healthy cats (60 Persians and 60 DSH) with swab and cellophane tape. RESULTS: Out of 103 (85.8%) organisms isolated from cats, 83 (80.6%) were identified as molds. infection with Dermatophytes were detected in 3 (5%) samples. Yeasts were also present in 20 (19.4%) cats. Based on the results of this study there wasn’t any significant difference in fungal flora of the ear canal between Persian and DSH cats. CONCLUSIONS: Ear canal and pinna in most of healthy cats harbor fungal filamentous and yeast organisms that maybe pathogenic in suitable conditions. Furthermore dermatophyte organisms in apparently healthy cats can be transmitted to their owners.

BACKGROUND: The study of rumen protozoan frequency and population diversity in different regions’ ruminants, moreover than increasing the information about diversity of protozoa, shows the relationship within the species of ruminants, partially. OBJECTIVES: The aim of this research was to study of ruminal ciliate population in one-humped camels of Baloochi (n=14) and Sindhi (n=6) strains. METHODS: The samples were collected from rumen after slaughter. Samples then were transferred into formalin bottles. At first, all the ciliates were counted and their genus and species were determined. RESULTS: The mean of ciliates were 29.4×104 in Baloochi and 35.6×104 in Sindhi camels per each milliliter of ruminal content. Entodinium dubardi, Diplodinium cameli, Epidinium ecaudatum, Epidinium caudatumand Caloscolex camelinuswere observed in both breeds. Frequency of Epidinium caudatum in Sindhi camels (15×104 per ml) was significantly higher than Baloochi camels (12×104 per ml; p<0.001). Diplodinium dentatumwas seen only in Baluchi (18.1×104 per ml), whereas Eudiplodinium maggiicould be observed only in Sindhi camels. CONCLUSIONS: The population of ciliated ruminal protozoa is very similar in two breeds. However, some of protozoa species exclusively present in one species of studied camels and are specific to the related host.

BACKGROUND: Honey has been generally used in traditional medicine for healing different kind of wounds. In this research complex, the clinical and histopathological effects of West Azarbayjan non-boiled honey in healing process of surgical wounds (cuts) were evaluated. OBJECTIVES: This study was performed to evaluate the effect of honey on healing time and duration of wound closing in dog. METHODS: 30 dogs, each weight was almost 25 kg, were divided into 2 clinical (n=10) and histopathological (n=20) groups. In each group, after surgical preparation and anesthesia surgical wounds were produced by a similar pattern and size (rectangle; 25×50 mm2) in the thoracolumbar region. Wounds on the left side arbitrary taken as treatment group and on the right side as control group. Postoperative treatment in the honey group was included daily wound irrigation with normal saline and then topical application of 20 g honey. In the control group only irrigation with normal saline was performed. Clinical and histopathological parameters were evaluated in each group 7, 14, 21 and 28 days after operation. RESULTS: Honey caused in acceleration an healing and surgical wound closure and in decreasing the level of infection and secretion in the experiment group in compare to control group which was more significant at days 14 and 28 (p<0.05). Decreasing the area of wound during experiment in honey treated group was 11.1% more than control group. From histopathological aspect, especially from the second week on, less neutrophilic chemotaxis was found in treatment group than in the control group and in treatment group the compact connective tissue was developed more rapidly. CONCLUSIONS: West Azarbayjan non-boiled honey is potentially effective in surgical wound healing.

BACKGROUND: Thyroid is an endocrine gland that influences many organs of the body and plays an important role in the metabolism of animals. However, little researches have been done about anatomical and histological characteristics of camel thyroid glands in Iran. OBJECTIVES: The aim of this study was to determine the anatomical and histological structure of thyroid gland in one-humped camel. METHODS: In this research, the anatomical characteristics and histological structure of the thyroid glands of 40, 6-10 year old one-humped, camels (20 males and 20 females) were studied by sectioning and staining with Haematoxylin & Eosin, Verhoeff and Toluidine blue by light microscope. RESULTS: The thyroid gland of one-humped camel was situated in lateral surface of the trachea. The right lobe was located slightly cranial to the left one lying on the caudal aspect of the larynx while both lobes were connected together by isthmus on the ventral surface of trachea. Maximum length, width and thickness of thyroid gland were 5.15±0.65, 2.25±0.75 and 0.9±0.5 cm, respectively in male camels and 5.55±0.5, 2.65±0.3 and 0.9±0.52 cm, respectively in female camels. Weights of the thyroid gland in male and female camels were 51.69±0.52 and 53.07±0.25 g, respectively. Histologically, the thyroid gland contained follicles, follicular epithelium and parafollicular cells in microscopic examination. The parafollicular cells were about 5% of the cell population. Large follicles were located in peripheral margin whereas small ones in central part of the gland. Central parts of the gland had richer vascular base in comparison with the peripheral parts. CONCLUSIONS: Anatomically and histologically, the thyroid gland of one-humped camel has no remarkable difference with other domestic mammals.

BACKGROUND: Phenol is a toxic organic chemical found in many foods and chemicals in our environment. OBJECTIVES: Regarding to the wide use of phenol and its harmful effects, this study was done to determine the effect of pure phenol on morphometrical and histometrical structure of testis. METHODS: 24 mature male Syrian mice divided to one control and 3 treatment groups that received pure phenol at 30, 75 and 100 mg/kg doses through gavage during 35 days. Finally, body, testis and tunica albuginea layer weight, gonadosomatic index (GSI) and length, width and thickness of the testis were measured. For histometrical assessment, the diameter of seminiferous tubules and the thickness of germinal layer were measured. RESULTS: Body weight in 75 and 100 mg/kg doses (2.02±4.09 and 2.33±3.35g, respectively) had significant decrease (p<0.05) comparing with control group (10.16±3.97g). The difference in weight, length, width and thickness of testis between treated groups and control group was not significant, but the GSI in 30, 75 and 100 mg/kg doses (0.53±0.11, 0.53±0.07, 0.5±0.07%, respectively) had significant increase (p<0.05) comparing with control group (0.088±0.0083%). Weight of tunica albuginea layer had increased significantly (p<0.05) only at dose of 75 mg/kg (0.01±0.006g) comparing with control group (0.002±0.002g). There were significant differences (p<0.05) in diameter of seminiferous tubules in control group (100.42±12.41mm) comparing with 30 mg/kg (130.18±49.14 mm) and 75 mg/kg doses (156.89±53.36mm) and thickness of germinal layer in control group (47.96±18.42 mm) comparing with 30 mg/kg (37.18±14.44 mm) and 75 mg/kg (30.13±50.04 mm) doses. CONCLUSIONS: Pure phenol can cause changes in body weight, GSI and histometrical structure of testis.

BACKGROUND: Recently several types of herbal immune and growth stimulants have been used in aquaculture troughout the world. OBJECTIVES: This study was performed to evaluate the effects of oral administration of Viscum album and Nigella sativa extracts, on survival rate, growth factors and resistance against Aeromonas hydrophila infection in gold fish. METHODS: 270 gold fishes were divided into 2 immune and non-immune groups and each group into 3 treatments; V.album, N.sativa and control (each with 3 repeats). Each treatment groups fed for 7 weeks with food supplemented with 0.5% of V.album, N.sativa or water. At the end of treatment, survival rate, growth factors and resistance to A.hydrophila infection were compared among the groups. RESULTS: Percentage of mortality in different groups were 9.33 to 12% and prescription of either extracts has no significant effect on survival of groups (p>0.05). Food conversion rate and percentage of weight gain were 2.56±0.31 and 131.6±25.05% in V.album treatment and 3.12±0.37 and 73.2±4.53% in control treatment, respectively which showed a significant increase (p<0.05), growth factors didn’t show any significant difference between N.sativa and control treatments (p=0.15). Mortality rate after bacterial infection showed a significant decrease in V.album treatment (p<0.05) in a way that mortality in V.album treatments of immune and nonimmune groups were 40 and 80% and in control treatment were 63.3 and 100%, respectively. N.sativahad no significant effect on mortality after challenge (p=0.45). CONCLUSIONS: Oral administration of V.album in gold fish has similar effects on immune and growth stimulation as those reported in other warm-blooded animals but N.sativa didn’t show such effects.

BACKGROUND: Zagros Pupfish (Aphanius vladykovi) is a native fish of Iran which is found in basins of Chahar Mahal & Bakhtiari province. OBJECTIVES: In this study, the chromosome number and karyotype of Zagros Pupfish were investigated. METHODS: To obtain metaphase chromosome spreadsin vivo, 1.2-5.4 g fish were injected intraperitoneally by 0.1-0.15 mg/g of 1% colchicine and were humanely killed after being incubated in a well-aerated tank for 4-5 hours at 22-23oC. Hematopoietic, testis or ovary, gill, spleen and liver tissues were isolated from the fish and were fixed with cold Carnoy's solution after being hypotonized in 0.075 M KCl. Chromosome spreads were prepared by either splashing of cell suspension or stamping of whole tissues onto slides. Slides were then stained by 10% Giemsa followed by microscopic observation. Suitable metaphase plates were digitally microphotographed and chromosomes were counted and karyotyped. RESULTS: Diploid chromosome number ranged from 42 to 49 with the modal number (2n) of 48. Based on the prepared karyotype, chromosome formula for this species was 12st+36 a/t and the number of chromosome arms (FN) was calculated 60. No heteromorphic sex chromosomes could be recognized in this species. CONCLUSIONS: The diploid chromosome number of Zagros Pupfish is similar to other species of the same genus so far investigated.

BACKGROUND: Changing in protein level and electrolyte balance in diets can be useful in improvement of performance in broilers exposed to heat stress. OBJECTIVES: This experiment was carried out to determine the effects of different levels of protein and electrolyte balance (DCAB) on performance and carcass traits in broiler exposed to heat stress. METHODS: 486 Ross, one-day old broilers were used in a completely randomized design with a 3×3 factorial arrangement in triplicate for a treatment. For performing this, 9 diets were formulated according to NRC recommendation with 3 different protein levels (100, 90 and 80% of NRC recommendations) and electrolyte balance (200, 260 and 320 meq/kg). The birds were exposed to heat stress (34±3oC) for 8 hours (10:00 to 18:00). RESULTS: Body weight gain in broilers fed containing 260meq/kg DCAB, were significantly (p<0.05) higher than those fed other levels of DCAB in other periods (starter, grower and total period). The electrolyte balance had significant effect (p<0.05) on feed intake in grower period (14.63 gr/day). Dietary protein levels had no significant effect on body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) in all periods. There was a significant interaction (p<0.05) between DCAB and protein levels on the BWG an FI (11.5 and 21.11 gr/day). Compared to DCAB 320 meq/kg, the DCAB 200 and 260meq/kg significantly decreased FCR (0.15 and 0.2, respectively), but FCR did not affect by protein levels. Dietary DCAB had significant effect (p<0.05) on carcass yield (3.25%), breast (1.63%) and relative weights of liver (0.26%) and gizzard (0.56%), but had no significant effect on thigh, heart and abdominal fat. The lower protein level did not affect on carcass traits, with the exception of carcass yield. CONCLUSIONS: 260 meq/kg DCAB and medium 90% protein level of NRC recommendation in heat stress can be used.