Journal of Veterinary Research
Year:2019 | Volume:74 | Issue:4|Papers Count:14

BACKGROUND: Urea is a non-proteinaceous nitrogen source, often used as a substitute for raw ration protein in order to reduce the feeding cost of livestock. OBJECTIVES: The purpose of this study was to investigate the effects of substitution of different levels of slow-release urea with soybean meal on feed intake, milk production and composition, and blood parameters of lactating cows in early lactation. METHODS: Twelve Holstein cows were selected at the third birthday, milk production of more than 30 kg per day, and from 10 to 100 days after birth, with four diets, the treatments included 0, 23, 0. 46 and 0. 69 % of slow-release urea was replaced by soybean meal. Feed intake was measured daily. The milk sample was taken on the day of the start of the experiment and was taken at intervals of 14 days. To measure glucose, urea, cholesterol, triglycerides, high density lipoprotein, and low blood levels, were determined from the start of the test to the end of the test every two weeks. RESULTS: Consumption of feed, milk production and composition did not differ from experimental treatments. Glucose concentration and blood parameters (cholesterol, high and low density lipoprotein) did not differ between experimental treatments, but triglyceride and lipoprotein showed a very low density at zero (P <0. 05). CONCLUSIONS: The results of this study showed that adding slow-release urea to the level of 0. 69% had no negative effect on feed consumption, milk production and composition, and blood parameters.

BACKGROUND: Staphylococcus aureus is one of the most important pathogenic microorganisms in meat products, especially those that are repeatedly handled by hand in the production process. Beta-lactam drugs, especially new generations of Cephalosporins, are used for treatment of most infections that are caused by Staphylococcus aureus. But the production of beta-lactamase enzyme by some strains has led to the failure for treating the infections that are associated with this organism. OBJECTIVES: The present study was conducted to evaluate the prevalence and comparison of the antimicrobial effect of methanolic extracts of red pepper and red onion on Staphylococcus aureus with beta-lactamase gene that was isolated from minced meat in Semnan city. METHODS: For this reason, sampling from 30 distribution and supply centers of packaged meat in Semnan city was performed in hygienic conditions and all of the samples were tested for presence of Staphylococcus aureus with beta-lactamase gene by biochemical methods and molecular confirmation by PCR assay. Also, the antibacterial effect of red pepper and red onion extracts on these isolates was evaluated by minimum inhibitory concentration (MIC), minimum bacterial concentration (MBC), well distribution and bacterial growth curve tests. RESULTS: The results showed that 16. 6 percent of samples were contaminated with Staphylococcus aureus with beta-lactamase gene. Red pepper and red onion extracts had good antibacterial effects on these isolates and in all the tests, the red pepper extract was more effective than the red onion extract. CONCLUSIONS: By proving stronger antimicrobial effect of red pepper, it is recommended to use pepper in sufficient amounts along with onion in foods that are made from minced meat like all kinds of Kebab.

BACKGROUND: The probiotic must survive in sufficient numbers after gastric and duodenal transit to be able to colonize the large intestine. The viability of a probiotic in the human upper GI tract is mainly influenced by low acidity of the stomach and bile salt in the small intestine. Currently, consumers are more interested in natural antibacterial compounds as food preservatives, like herbal essential oils and extracts. To provide a balance between sensory acceptability and antimicrobial efficacy, the use of sublethal concentrations of EOs in combination with other preservation methods has been proposed. However, it should be considered that bacterial cell exposure to sublethal stresses may result in decreased sensitivity to the same stress and even to other stresses. OBJECTIVES: The aim of this study was to evaluate the stress response of probiotic strain Lactobacillus rhamnosus GG, pre-exposed to sublethal level of Ziziphora clinopodioides EO. METHODS: The sublethal and lethal levels of Ziziphora clinopodioides EO, bile salt and pH stresses were determined for Lactobacillus rhamnosus GG. Then stress response of Lactobacillus rhamnosus GG pre-exposed to the sublethal level of Ziziphora clinopodioides EO were compared to cultures which were challenged directly with the lethal level of each stress (control). The growth of Lactobacillus rhamnosus GG was also assessed under bile salt and acid pH stress condition. RESULTS: The sublethal and lethal levels of Ziziphora clinopodioides EO and the lethal level for bile salt and pH were 1000 ppm, 1500 ppm, 0. 2% and 2. 5 respectively. In the test tubes, the number of cells that survived increased significantly and the growth curve of Lactobacillus rhamnosus GG has been affected in pre-exposed cultures. CONCLUSIONS: Exposure to sublethal concentration of Ziziphora clinopodioides EO can induce cross-protection against bile salt and pH stresses.

BACKGROUND: European chub (Squalius cephalus) is a member of Cyprinidae family and is classified as fresh water fishes which live in a group in roaring rivers. Siahrood runs from the south east to the Caspian Sea. OBJECTIVES: The main objective of this study was determination and identification of parasites of European chub in the Siahrood river. METHODS: In the current study, a total number of 96 fishes with average weight of 42 ± 3 gr and average length of 15 ± 1 cm were collected during winter, spring, summer and autumn 2015. The collected fishes were transported to parasitology lab with oxygenated plastic bags and were kept in aquarium till examination. Sample collection was conducted from skin, gills, fins and eyes and prepared wet mount was studied with optical microscope. Samples which are positive for presence of parasite were fixed and identified at the level of genus or species by biometric characterization and identification keys. RESULTS: In the present study, 6 species of endo parasites and ecto parasites were detected from different organs of Siahrood’ s European chubs that included: 2 protozoan species from gills, Ichthyophthirius multifiliis with the highest positive samples in summer; Trichodina sp. with the highest positive samples in spring; 1 Myxozoa species from the intestine, Myxobolus muelleri with the highest positive samples in winter; 3 Monogenea species, Dactylogyrus vistulae and Diplozoon paradoxum from the gills with highest positive samples at autumn and summer respectively; Gyrodactylus mutabilitas from the gills and the skin with the highest positive samples in summer. CONCLUSIONS: It seems the major factors affecting the variable presence of parasites in different seasons are ecological and environmental variation of the river in different seasons and the effects of these changes on fishes physiology and parasites life cycle.

BACKGROUND: Silver nanoparticles are now widely used in various industries and consumer products, especially because of their antimicrobial properties. The widespread use of these nanoparticles has increased the likelihood of their release to aquatic ecosystems and their effects on aquatic organisms. OBJECTIVES: The purpose of this study was to investigate the histopathological effects of waterborne silver nanoparticles on the gills of Caspian brown trout. METHODS: In this study, 84 fish (27. 46± 4. 3 g) were tested in four concentrations of silver nanoparticles (0, 0. 01, 0. 02 and 0. 03 mg/L) for 14 days. At the end of the experiment, gill tissue was evaluated to determine the effects of tissue damage caused by silver nanoparticles. RESULTS: Observed tissue damage included hyperplasia, hypertrophy, curvature of secondary lamellae, shortening of second lamellae, separation of epithelium from lamellae and aneurism. CONCLUSIONS: The results of this study showed that colloid silver nanoparticles in water could lead to tissue damage in the gills of Caspian brown trout, and long-term exposure to the sublethal concentrations of these nanoparticles can cause fish death.

BACKGROUND: Safflower plant can be used in fish due to its antioxidant properties. In the present study, the side effects of intraperitoneal injection of safflower extract in rainbow trout have been investigated. OBJECTIVES: The effect of the intraperitoneal injection of Safflower (Carthamus tinctorius) extract on Aspartate aminotransferase, Alanine aminotransferase and Alkaline phosphatase as tissue damage indicators and also the histopathologic analysis of kidney and liver tissues in rainbow trout (Oncorhynchus mykiss) have been investigated. METHODS: To this end, rainbow trout with an average weight of 100 ± 5 gr were supplied and intraperitoneally injected with different levels of Safflower extract. In this regard, one negative control group (with no injection), one positive control group (injected with 0. 2 ml normal saline) and three treatment groups (injected with 50, 100 and 200 mg/kgbw of safflower extract, respectively) were considered. Blood samples were taken on the third, seventh and tenth days after injection, in order to isolate blood serums and analyze the ALP, ALATA and ASAT activities. Kidney and liver tissue samples were also taken on the seventh-day post injection. RESULTS: The levels of ALP, ALATA and ASAT activities significantly increased in all treatment groups that received safflower extract compared to control groups in all samples (sig<0. 05). In histological analysis typical pathologic effects were recorded in kidney and liver tissue sections. CONCLUSIONS: Intraperitoneal injection of Safflower extract at dosages of 50-200 mg/kgbw led to damage in the liver and kidney tissues, so that the concentration of 200 mg / L had severe histological complications in these tissues. Hence some limitations must be taken into account for using this extract as immune-stimulant or vaccine adjuvant.

BACKGROUND: Lameness is regarded as a serious issue in dairy cattle which can ultimately lead to a drastic reduction in milk production as well as conception, and the possibility of early removal of cattle from the herd. Short claw and thin sole play the chief role in excessive pressure on the heel and lateral grooves, which in turn are the direct consequences of heel erosion and lameness. OBJECTIVES: Current study intended to investigate the simultaneous occurrence of these two events at epidemic proportions in cattle. METHODS: This study was performed in 110 Holstein newborn heifers. Lame cows were chosen based on the fact sheet approved by AABP, (the American Association of Bovine Practitioners). The “ Thin sole” criteria included a length of ˂ 7. 5 cm at the posterior wall, along with ˂ 5 cm in sole (measured by claw check). Existence of dark V-shape lesions in lateral grooves was considered as heel horn erosion. RESULTS: In 50 newborn heifers, thin sole and lateral grooves ulcer which affect rear limb digits almost equally, were diagnosed and clinically approved. The lowest posterior wall (66. 54 ± 1. 02 mm) and the lowest sole thickness (43. 98 ± 1. 78 mm) were observed in the left hind limb. CONCLUSIONS: According to the results of this study, these two above mentioned conditions are called “ New Concrete Disease” and the lameness due to these two lesions was clinically considered.

BACKGROUND: Minimally invasive methods are desirable and important for therapeutic purposes and animal modeling of intervertebral disc disease. Most therapeutics and models are delivered and induced invasively rather than minimally invasively. Application of minimally invasive approaches in intervertebral disc, which is closed to critical structures, would be advantageous. OBJECTIVES: The objective of this study is to introduce and evaluate a new approach for percutaneous needle placement using computed tomography for injection and aspiration of the canine lumbar intervertebral disc. METHODS: This study was performed on eighteen healthy dogs in two different intervals. In each interval, three intervertebral discs were chosen and a spinal needle with suitable gauge were inserted at the center of the disc through the annulus fibrosus into the nucleus pulposus using computed tomography. RESULTS: Accuracy and agility of needle placement showed better results with progression of study. The number of needle placement in proper position was one time minimally and three times maximally. Only in 10. 2% of cases was minor hemorrhage observed in needle puncture site. The average time for placement of every needle was 141 s. No unexpected complication was observed. CONCLUSIONS: Needle placement into the canine intervertebral disc could be applied in a simple and fast procedure for therapeutic and research purposes without any complication.

BACKGROUND: In order to compensate for the elimination of antibiotics from the poultry industry, finding suitable alternatives to improve the productive traits and the health of the birds is essential. Among them, naturally occurring compounds and additives are one of the best options in this regard. OBJECTIVES: The aim of this study was to evaluate the effects of sodium humate and probiotic application and their interactions on feeding broiler chicks on biochemical, immunological and blood metabolites of broiler chicks. METHODS: 336 male broiler chicks (Ross 308) were used from 1 to 42 days old. A 3×2 factorial experiment on the basis of completely randomized design was done with four replications. Experimental factors were: three sodium humate levels (0, 0. 35 and 0. 45% of diet) and two probiotic levels (0 and 0. 02% of diet). RESULTS: The best feed conversion ratio was obtained at the finisher 1 and 2 and the whole period at the use of 0. 35% of diet (P ≤ 0. 05). The highest live weight of the last course was obtained in the treatment of 0. 35% sodium humate in diet (P ≤ 0. 05). The production index improved at a level of 0. 35% of sodium humate compared to other treatments (P ≤ 0. 05). The percentage of carcass was higher in the group receiving probiotic and sodium humate than the control group. The abdominal fat pad percentage was lower in the probiotic and humate sodium group than in the control group (P<0. 05). In terms of interactions, villi length was highest in treatments receiving 0. 35 of sodium humate and 0. 02% of probiotic in diet, as well as 0. 45% of sodium humate and 0. 02% probiotic in diet (P<0. 05). The highest levels of SRBC and G-type immunoglobulin were obtained in groups receiving 0. 45% sodium humate and 0. 02% probiotic in diet. CONCLUSIONS: In conclusion, use of sodium humate about 0. 35% and probiotic 0. 02% in diet of broiler chicks improves the growth performance, carcass traits and morphological characteristics of the intestine.

BACKGROUND: One of the important parts of the cardiovascular system is the cardiac vessels. Ultrasonography which is the method of choice for evaluating the heart and vessels in all living animals can also be used in this fish. OBJECTIVES: This study was conducted to make a full understanding of the anatomic and echocardiographic characteristics of these vessels in beluga and suggest standard methods of ultrasonography for this species. METHODS: In this study, a total of 10 immature belugas were selected. The transducer was placed on the ventral surface of the body, between pectoral fins and transverse and sagittal images were obtained. By moving the anterior and posterior regions the vessels were investigated. After the ultrasound examination, anatomic studies were performed. Length and diameter of the vascular compartment were measured and analyzed by SPSS 16 software and Paired Sample T – method (P>0. 05). RESULTS: In ultrasonography, blood flow was visible because of the movement of echoic particles. Two precardiac vessels joining between the liver lobes constituted and common vascular compartment before entering the sinus venosus. In the anatomical study, the ventral aorta was bifurcate near the gills. The right liver adjacent to the vessel was shorter and wider than the left one. Moreover, the common vascular compartment was shorter and wider than the liver adjacent to the vessels. The ventral aorta was longer and wider than the right precardiac vessel and common vascular compartment but was shorter than the left precardiac vessel (P>0. 05). CONCLUSIONS: Due to lacing thorough anatomic and ultrasonographic studies concerning the cardiac vessels in this species, this study can be a cornerstone for further researches of this kind. In this study the long left precardiac vessel is named Common cardinal vein and wide right vessel is named Hepatic vein.

BACKGROUND: Phytase enzyme (EC 3. 1. 3. 8), is used to increase the availability of phosphorus in the feeding of monogastric animals. Increasing public attention to environmental issues, improving livestock nutrition and human health have led to considerable attempts to increase its activity or prevent its inhibition as a food additive. OBJECTIVES: Determination of inhibitory or activating effect of methanolic extract from aerial parts of some herbs, as rich sources of secondary metabolites. METHODS: Phytase was partially purified from wheat barn. After preparation of methanolic extracts from aerial parts of plants, their effects on phytase activity were measured at four concentrations of 0. 001, 0. 01, 0. 1 and 1 mg/ml. Micro plate assays were performed at 405 nm. RESULTS: Among analysed plant samples, extracts from Pedicularis sibthorpii Boiss, Phlomis persica Boiss, Solenanthus Circinatus Ledeb, Stachys lavandulifolia Vahl, had appreciable inhibitory effect, while extracts from Astragalus caraganae Hohe, Hypericum scabrum L, Linum album Ky. ex Boiss, Valeriana sisymbriifolia Vahl, Euphorbia denticulate Lam, Rindera lanata (Lam. ) Bge, had a considerable activation effect. CONCLUSIONS: According to the results of this report, plants with positive effect on phytase activity, could be used as food additive along with phytase to improve phosphoros uptake. On the other hand, plants with negative effect on phytase could be viewed as unwanted sources in monogastric animals feeding.

BACKGROUND: The histogenetic study is a useful and practical laboratory method for obtaining basic and effective information in order to reveal the process of histogenesis and development of organs in different stages during the embryonic period. This applied method helps us to understand the formation time of each organ and its tissue structure. OBJECTIVES: The aim of the present study was to study the histogenesis and histochemistry of the pheasant liver during the embryonic period. METHODS: Sixty fertile eggs were placed in the incubator and sampling was performed from day 5 to the end of incubation period. The liver samples were fixed in 10% Buffered Formalin and the slides were stained with Hematoxylin and Eosin (H&E), Periodic Acid Schiff (PAS) and Masson Trichrome (MT). RESULTS: In this study, liver parenchyma, changes in the hepatocytes and their glycogen storage, as well as the appearance time of canaliculi, biliary ducts, central veins and port spaces were investigated. CONCLUSIONS: Differences in the time of the formation of the organs and structures in various birds relate to different incubation period or species variations. In this research, as the first study on the liver histogenesis of the pheasant, the formation of this organ from the fifth day to the end of the fetal period was examined and it was observed that the evolution and tissue development of the liver is completed until the eighteenth day of incubation period.

BACKGROUND: Antibacterial drug use in food producing animals, in addition to the very beneficial effects on the prevention, treatment, and control of infectious diseases, can lead to health risks including microbial resistance and drug residues. This survey was conducted due to the lack of information on the status of antibacterial drug use in dairy farms of Qom province. OBJECTIVES: To study the usage pattern of antibacterial drugs and compliance with public health-related measures in dairy cattle farms in Qom province. METHODS: In this study, 100 dairy herds were surveyed in three areas of Qom province including the southern part (Kahak), West (Jafar-abad and Khalajestan) and central part (Qom and the suburbs) using a questionnaire and direct interview. RESULTS: Injectable oxytetracycline, tylosin, penicillin + streptomycin were the most frequently used antibacterial products in dairy farms of Qom province (94%, 89% and 87%, respectively). A range of other antibacterial drugs showed high percentages of usage, as well. Among the 9 intramammary products, Tetranebalon® /Mastijet Forte® and Linconeocin MC® with 50% and 40% of frequency were the most commonly used products. Also, in a significant percentage of dairy farms, the milk collected from livestock treated with antibacterial drugs for mastitis (35%) or other illnesses (41%) was introduced into the milk reservoirs to be used in humans. CONCLUSIONS: In Qom province, there was an overuse of antibacterial drugs and high percentage of dairy farm units that did not follow the principles of rational drug therapy and the withdrawal times of milk and meat. This could be due to inadequate awareness of livestock workers regarding the public health implications of using these drugs and insufficient monitoring of veterinary authority in the province.

BACKGROUND: Chicken major histocompatibility complex region (MHC) is important in the productive traits, immune responses, resistance to infectious diseases and phylogenetic relationships. OBJECTIVES: This study was investigated for single nucleotide polymorphisms of MHC region related to the immune system in commercial broiler and layer chickens. METHODS: One hundred blood samples were taken from commercial broiler and layer chickens and genomic DNA was extracted by salting out method. The allelic polymorphisms were investigated in B-L, B-F and B-G loci using PCR-RFLP and MspI enzyme. RESULTS: For two commercial broiler and laying populations, in the 374 bp locus of B-L, only BB genotype was detected but in the 1048 bp locus of B-F, two genotypes of CG and GG were identified in broiler chickens. The C allele contained four bands of 515, 410, 75 and 47 bp, and the G allele with five bands of 410, 302, 213, 75 and 47 bp. In B-G (401 bp) locus, three genotypes of MM, MN and NN and two alleles of M with one band (401 bp) and N with two bands (350 and 51 bp) were identified. In total populations, the Shannon information index was calculated to be 0. 45 and 0. 73 in markers loci of B-F and B-G, and the fixation index values were-0. 20 and 0. 34, respectively. The highest observed heterozygosity index for B-F and B-G loci was 0. 34 and 0. 23, respectively. CONCLUSIONS: Considering the confirmation of the presence of polymorphism in two loci of the B-F (in commercial broiler population) and B-G (in commercial broiler and layer populations), these sites can be used as genetic marker in breeding programs to increase resistance to diseases.