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101.
Bovine leukemia virus (BLV), the causative agent of enzootic bovine leukosis (EBL) is an exogenous C-type oncovirus in the Retroviridae family. It causes significant economic losses associated with the costs of control and eradication programs due to carcass condemnation at slaughter and restrictions of export of cattle and semen to importing countries. The main objective of this research was to determine the seroprevalence of BLV infection in cattle herds in central region of Iran (Isfahan province) using a commercial enzyme-linked immunosorbent assay (ELISA) to detect serum antibodies against BLV. Samples of blood serum were collected from 403 female dairy cattle (Holstein-Friesian) from 21 livestock farms and 303 animals (81.9%) were BLV seropositive. A significant association was found between age as a potential risk factor and BVL seroprevalence with animals ≥ 4 years (86.6%) having a significantly (χ(2) = 35.6, p < 0.001) higher seroprevalence compared to those < 4 years (54.2%). We found no significant statistical association between seroprevalence and pregnancy, lactation status and farming systems as potential risk factors in this study (p > 0.1). It is concluded that BLV infection is a very common problem in the study area. Hence, control measures should be instituted to combat the disease and further studies are required to investigate the impact of this disease on dairy production in the country.  相似文献   
102.
ABSTRACT

This study was conducted to evaluate the effects of marshmallow extract (Althaea officinalis L.) administration on blood cells and biochemical parameters of carp liver. A total of 150 carps (Cyprinus carpio, initial body mass of 37.7 ± 4.4 g) were fed diets containing 0.0 (control diet), 2.5, 5, and 10 g marshmallow extract for 60 days. On days 30 and 60 of the experiment blood samples were collected and hematological parameters and liver enzyme activities—aspartate aminotransferase (AST), alanine amino transferase (ALT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP)—were measured. No significant difference was found (p > .05) in red blood cells (RBC); hemoglobin concentration (Hb); hematocrit (Htc); mean corpuscular volume (MCV); mean corpuscular hemoglobin concentration (MCH); or the percentage of neutrophils, basophils, and eosinophils in fish fed with different concentrations of marshmallow extract on days 30 and 60. However, the white blood cell (WBC) count was increased significantly in the fish fed for 60 days with feed supplemented with 5 g marshmallow extract (p < .05). The MCHC was increased signi?cantly in ?sh fed with diets supplemented with 2.5 g marshmallow extract for 60 days (p < .05). Administration of marshmallow extract (5 g) significantly increased (p < 0.05) lymphocytes on days 30 and 60. However, dietary intake of 10 g marshmallow extract had significantly decreased the monocyte percentage after 60 days. A significant increase was observed in AST, ALT, ALP, and LDH levels in livers of fish fed with extract 10 g, which may be attributed to cytotoxicity. However, marshmallow extract 2.5 and 5 g did not have adverse effects on liver enzymes. These results indicate that preclinical dietary supplementations of 2.5 and 5 g marshmallow extract per kg diet have no side effects on common carp.  相似文献   
103.
The objective of the study was to examine the effects of biofloc technology on the muscle proteome of Litopenaeus vannamei. Two biofloc treatments and one control were compared: biofloc‐based tanks under zero‐water exchange fed with 150 g/kg crude protein (BF15), or with 250 g/kg crude protein (BF25) diets, and clear water tanks with 50% of daily water exchange stocked with shrimp fed with similar amount of a 250 g/kg crude protein diet, referred to as control. The shrimp (5.28 ± 0.42 g) were divided into the 300‐L fibreglass tanks (water volume of 200 L) at a density of 35 shrimp per tank and were cultured for 35 days. The biofloc groups displayed better growth and survival compared to the control. The muscle tissue from the control and BF25 groups was subjected to proteomic analysis. Lactate dehydrogenase, enolase, arginine kinase, mitochondrial ATP synthase subunit alpha, mitochondrial ATPase inhibitor factor 1 precursor, serpin 3 and myeloid differentiation factor 88 had an increased abundance in the BF25 group, while myosin heavy chain type 1 and myosin heavy chain type 2 showed a decreased abundance. The results indicate that biofloc technology could alter the expression of proteins involved in structure, metabolism and immune status of cultured shrimp.  相似文献   
104.
A study was conducted to determine the effects of dietary protein and lipid concentrations on growth, spawning performance and egg quality of yellowfin sea bream, Acanthopagrus latus. Nine diets representing a combination of three protein concentrations (40, 50 and 60%) and three lipid concentrations (15, 20 and 25%) were tested with three replicates. Each replicate was stocked with 10 fish with a sex ratio of 1:1 and the average weights were 415 g and 236 g for females and males, respectively. Fish were fed to satiation twice daily. The weight gain of A. latus broodstock was not significantly (P > 0.05) different among fish fed diets with the various protein and lipid concentrations. Except for relative fecundity and survival rate of 3-day-post-hatch (3DPH) larvae, spawning performance of A. latus was not significantly affected by different concentrations of dietary protein or lipid. Relative fecundity was found to be significantly elevated by dietary lipid at 20% concentration. However, survival rate of 3DPH larvae was highest from broodstock fed diets with 40% protein and 25% lipid, 50% protein and 15% lipid and 60% protein and 15% lipid concentrations. Egg diameter generally increased with increasing dietary protein from 40 to 60% at each lipid concentration. Total length of hatchlings followed an inverse relationship with dietary protein regardless of the lipid concentration. The oil globule diameter (OGD) of hatchlings significantly increased with decreasing dietary protein from 60 to 40%. Yolk sac length (YSL) and OGD of hatchlings was generally greatest at 15% dietary lipid concentration irrespective of protein concentrations. Total length of 3DPH larvae was greatest from broodstock fed diets with 50% protein and 20% lipid, respectively. Body protein content of broodstock was not significantly affected by dietary protein and lipid concentrations. However, increasing dietary lipid generally resulted in increasing body lipid content regardless of the dietary protein concentration. Protein and lipid contents of eggs, hatchlings and 3DPH larvae were significantly affected by dietary protein and lipid concentrations of the broodstock diets. The present study revealed that the best reproductive performance of A. latus broodstock was achieved at 40% dietary protein and 20% dietary lipid concentrations based on relative fecundity, fertilization rate, hatchability and survival of 3DPH larvae.  相似文献   
105.
The present study was conducted to investigate the effects of fenugreek seed meal (FKSM) on growth performance, blood haematological and biochemical factors, survival and stress resistance of the common carp (2.46 ± 0.06 g) fingerlings. Four practical diets containing 0 (control), 0.5%, 1% and 1.5% FKSM were used to feed fish. Fish were fed on the tested diets at a rate of 3% of body weight for 8 weeks. Results indicated that fish fed the control diet had a significantly lower weight gain, specific growth rate and condition factor compared to the other treatments (P < 0.05). Feed conversion ratio decreased significantly in fish fed diets containing FKSM. There were no significant differences in glucose levels, red blood cell count, haematocrit and haemoglobin between treatment groups and the control group (P > 0.05). Significantly lower white blood cells count was observed in fish treatment with FKSM when compared with the control group (P < 0.05). The cholesterol level in group fed supplemented diet by 1% fenugreek significantly lower than other groups (P < 0.05). Total protein levels were significantly higher in all treatments compared to the control (P < 0.05). No mortality was recorded during the feeding trial. In salinity stress experiment, highest survival rate belong to fish fed supplemented diet by 1% fenugreek. These results indicate that FKSM can be considered as a beneficial dietary supplement for improving the growth performance and blood indices of common carp fingerling.  相似文献   
106.
This study was conducted to investigate the effect of glutathione-supplemented INRA82 extender on miniature Caspian stallion sperm quality during storage at 5°C. A total of 12 ejaculates from three stallions (four ejaculates from each stallion) were collected and diluted with INRA82 extender that included different concentrations of glutathione (0 [INRA-G0], 5 [INRA-G5], and 10 mM [INRA-G10]) and stored for 48 hours at 5°C. Sperm motility (computer-assisted sperm analysis), plasma membrane integrity (eosin–nigrosin staining) and functionality (hypo-osmotic swelling test), and malondialdehyde (MDA) level were determined during storage at 5°C. The results showed that the sperm total and progressive motility and plasma membrane integrity and functionality in all extenders were significantly decreased with increasing storage time. However, the MDA level in all extenders was significantly increased with increasing storage time. Also, the results showed that most of the evaluated sperm quality parameters in the present study, with the exception of MDA, were significantly greater in INRA-G5 than in INRA-G0 and INRA-G10 after 24 and 48 hours of storage at 5°C. We have concluded that supplementation of INRA82 with 5 mM glutathione can improve miniature Caspian stallion sperm quality during storage at 5°C by increasing total and progressive motility, plasma membrane integrity and functionality, and decreasing the MDA level compared with INRA-G0 and INRA-G10. More advanced in vitro evaluations and artificial insemination are required to reveal the exact effects of INRA-G5 on miniature Caspian stallion sperm quality and its fertilizing ability.  相似文献   
107.
A six‐week feeding trial was conducted to determine the effect of butyric acid (BA) inclusion in diet on performance of Barramundi (Lates calcarifer). Fish (12.0 ± 0.2 g) were fed with four experimental diets contained 0.0 (control), 2.5, 5.0 and 10.0 g BA/kg in triplicate. Fish fed on 5 and 10 g BA/kg diets had higher growth and total alkaline protease and lipase activities than the other treatments. Fillet protein content in BA‐supplemented groups was higher than the control. Liver catalase activity was highest in 2.5 g BA/kg group compared with the other groups. The values of liver superoxide dismutase activity and serum total protein concentration in 5 and 10 g BA/kg treatments were higher than those in the control (p < .05). Moreover, the highest and the lowest levels of serum lysozyme activity were noticed in the 10 g BA/kg and the control groups, respectively (p < .05). Also, the highest respiratory burst activity was observed in fish fed 5 g BA/kg feed. Supplementing diet with 2.5 or 5 g BA/kg resulted in higher serum haemolytic activity in fish compared with the other groups. The number of red and white blood cells increased in fish fed BA‐supplemented diets compared with the control (p < .05). In conclusion, the results of this study showed inclusion of BA at 5 g/kg diet in L. calcarifer juveniles improved growth and upgraded the general health condition by enhancing fish antioxidant enzyme activities and haemato‐immunological responses.  相似文献   
108.
Microorganisms such as fungi are one of the most important factors that cause oxidative processes during postharvest stage and consequently deterioration of agriculture products would not be unexpected. On the other hand, high antioxidant properties of industrial by-products of pomegranate propose them as powerful antioxidant and antifungal substances. So to investigate the antioxidant and antifungal properties of pomegranate, two independent factorial experiments based on randomized design with 5 replications were conducted. In the first experiment the effect of 3 different parts of pomegranate (peel, seed and leaf) and 2 different kinds of extracts (aqueous and methanolic) with 4 concentrations (0, 500, 1000 and 1500 ppm) were investigated on 3 postharvest fungi (Penicillium italicum, Rhizopus stolonifer and Botrytis cinerea). In the second experiment antioxidant capacity and phenolic content were measured for two different extracts from different parts. Based on the results the methanolic extract showed the highest inhibitory effects on the mycelia growth (IMG) and spore germination (ISG) with 49.82 and 41.25% respectively. On the other hand, peel and seed extracts had more inhibitory effect (IMG and ISG) than leaf extract. The phenolic content of peel extract were also measured 2.8 fold higher than pomegranate leaf extract and antioxidant capacity of peel, seed and leaf extracts of pomegranate were 55.3%, 35.7% and 16.4% respectively. Therefore, it seems that the high percentage of phenolic content in the peel and seed of pomegranate could cause the high antifungal and antioxidant activity of their extracts.  相似文献   
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