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551.
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   
552.
Caprine arthritis encephalitis (CAE) is a chronic debilitating disease of goats caused by a lentivirus responsible for economic losses as a result of a drop in milk production and weight loss. The objective of the study was to determine if indigenous goats from five different regions in the Sultanate of Oman exhibit serological evidence of exposure to CAEV using a competitive-inhibition ELISA technique. Blood samples were collected from slaughtered goats (N = 1,110) and from the National Serum Bank (n = 528). In total, 83 (5.1%) of screened samples were classed as seropositive. The results provide the first serological evidence for the presence of CAEV in Oman.  相似文献   
553.

Purpose  

Nigeria is the largest cattle-rearing nation in Africa with most animals kept under traditional husbandry practices. While bovine brucellosis does not receive much attention, a relatively high seroprevalence is found in samples submitted for laboratory testing. The aim of the study was to provide serological evidence of brucellosis in cattle from some of the main cattle-rearing states of the country and to validate a simple and rapid field test for the serodiagnosis of bovine brucellosis.  相似文献   
554.
Two experiments were conducted to investigate the effect of phytase and/or multienzymes (protease, amyloglucoidase, xylanase, B-glucanase, cellulose, and hemicellulase) on improving the utilization of date pit (DP) in laying hens. In the first one, DP completely replaced corn in four isocaloric and isonitrogenous diets: (1) DP50 without additives, (2) DP50?+?500 FTU phytase/kg, (3) DP50?+?0.1 % multienzymes, and (4) DP50?+?500 FTU phytase/kg?+?0.1 % multienzymes, in addition to the diet without DP. In the second experiment, DP was included at 0 %, 15 %, and 30 % in isocaloric and isonitrogenous diets. Meanwhile, diets containing 15 % and 30 % DP (DP15 and DP30) were fed without or with 500 FTU phytase/kg diet and/or 0.1 % multienzymes. In both experiments, each diet was fed to six groups of five hens housed individually (520 cm2 per hen) during 30–42 and 28–42 weeks in the first and second experiment, respectively. In the first experiment, productive performance and shell quality of laying hens significantly decreased due to complete substitution of corn, but fertility and hatchability were not affected. Phytase, multienzymes supplementation did not restore laying performance to the control level. The results of experiment 2 indicated that DP could be included in laying hens diets up to 30 % when supplemented with multienzymes.  相似文献   
555.
Jasmine moth (JM), Palpita unionalis (Hübner) (Lepidoptera: Pyralidae) is a very important pest in the commercial, densely planted olive orchards in Egypt. In years of its highest population density, it can destroy a significant part of the crop. The objectives of this study were to determine the male flight trend and egg laying trend of the JM in three large plots of different olive varieties (two varieties/plot) in two successive fruiting seasons. Differences in male flight trend and egg laying trend of JM were observed among the different varieties (??Sennara??, ??Toffahi??, ??Shamy??). In 2003, more males were captured in traps placed in the Sennara/Toffahi plot than in the two Shamy/Toffahi plots. Egg densities were higher on Toffahi trees grown between Sennara trees than on Toffahi trees grown between Shamy ones. In 2004, in the plot where Toffahi and Sennara were grown together, JM females laid more eggs than in the olive plot where Toffahi rows alternated with Shamy rows. The results suggest that the Shamy variety discouraged gravid females from ovipositing, compared with Toffahi or Sennara varieties. In conclusion, olive variety, cropping system (mixed culture) and trapping season are among those characteristics that affect this pest.  相似文献   
556.
Toxoplasma gondii is widely distributed in humans and other animals including domestic poultry throughout the world, but the data on prevalence of T. gondii in free-ranged (FR) chickens in People's Republic of China (PRC) are limited. In the present study, the seroprevalence of T. gondii infection in FR chickens was investigated in 13 provinces/municipalities of China during the period from January to June 2010. A total of 1173 serum samples were collected and assayed for T. gondii circulating antigens (TCA) and antibodies (TCAb) using enzyme linked immunosorbent assay (ELISA) technique. Out of this number, 199 samples were TCA positive (16.97%), 226 samples were TCAb positive (19.27%), 69 samples were positive for both TCA and TCAb (5.88%), and the total seropositive rate was found in 356 of 1173 (30.36%). The results of the present survey indicated that infection with T. gondii in FR chickens is widely spread in China.  相似文献   
557.
In the present study matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) was evaluated for species identification of 98 bacteria previously classified phenotypically and genotypically to genera Arcanobacterium and Trueperella. Species identification was carried out by comparing the main spectra of each strain with the main spectra of reference strains of both genera and 3740 database entries included in the MALDI Biotyper 2.0 software package (Bruker Daltonik GmbH, Bremen, Germany). MALDI-TOF MS correctly identified (log (score) values ≥ 2.0) all investigated strains of the species A. (T.) bialowiezense (n=3), A. (T.) bonasi (n=7), A. haemolyticum (n=10), A. pluranimalium (n=1) and A. (T.) pyogenes (n=77). According to the present results MALDI-TOF MS had a comparable discriminating power than previously conducted tests on DNA level. Further studies with strains isolated from human infections would show the robustness of MALDI-TOF MS for identification of bacteria of these genera.  相似文献   
558.
OBJECTIVE: To compare bursting strength and failure modes of ventral median abdominal incisions closed with loop suture in a simple continuous pattern using two different suture-bite intervals. STUDY DESIGN: In vitro experiment. SAMPLE POPULATION: Equine cadavers (n=14; weighing >318 kg; postmortem interval <2 hours). METHODS: A template was used to make a 25 cm incision with suture interval and bite size of either 1.0 cm x 1.5 cm or 1.5 cm x 1.5 cm. A 200 L polyurethane bladder was inserted within the abdomen and insufflated to create abdominal wall tension. Celiotomies were closed with a #2 braided lactomer 9-1 continuous pattern with a loop suture. Deviation from the linea, closure time (minutes), total suture length (cm), suture length to wound ratio (SL:WL), bursting pressure (mm Hg), and failure modes (fascial or suture) were compared between groups using a Mann-Whitney U test. Significance was set at P<.05. RESULTS: No significant differences were identified between closing time, total suture length used, SL:WL, bursting pressure, or failure mode. Fascial failure was the main failure mode for both techniques; suture failure occurred rarely and knot failure did not occur. CONCLUSION: Based on the overall bursting pressure and failure mode, #2 braided lactomer loop suture placed in a continuous pattern should provide sufficient security for closure of the equine linea alba during recovery and the immediate postoperative period. CLINICAL RELEVANCE: Although there were no significant differences in the 2 patterns evaluated, the 1.5 cm x 1.5 cm pattern may have potential advantages for closure time, less total suture remaining in the wound, and strength.  相似文献   
559.
Whole blood, red blood cells (RBC), and plasma vitamin E (VE) levels in chicks fed dietary VE (dl-alpha-tocopheryl acetate, dl-alpha Ta) supplementation in steps of 0.0, 5.0, 10.0, 15.0, 20.0 and 30.0 mg/Kg were determined to examine their usefulness as an index of VE status. The increase in VE level was significant and linear in whole blood (r = 0.90), RBC (r = 0.89) and plasma (r = 0.93) in response to dietary VE intake. There was a close correlation between VE in plasma vs whole blood (r = 0.90), plasma vs RBC (r = 0.91) and whole blood vs RBC (r = 0.95). The plasma VE content was 1.2-1.8 times greater than that of whole blood, and 6.6-12.5 times greater than that of RBC. The plasma total lipids content was not affected by the dietary VE intake, whereas the level of VE in the plasma total lipids was significantly increased with increasing supplementation. Alpha tocopherol was the major isomer (ca 92%) of VE in whole blood, RBC and plasma at hatching. The small proportions of beta-tocopherol (ca 2%), gamma-tocopherol (ca 5%) and alpha-tocotrienol (ca 1%) observed at 1 day of age had decreased or totally disappeared by 7 days of age after feeding the VE-free basal diet. The data showed that in the chick, the whole blood and RBC levels of VE were as sensitive and reliable indexes of dietary VE status as was that of the plasma.  相似文献   
560.
Six cases of intersex goats were investigated. Five of these animals had testicular tissues (testes) situated prepubically inside a skin pouch. The testicular tissues of the sixth goat were attached to the sides of the urinary bladder. All of the four animals that were studied by radiography, surgical exploration and/or pathology had uterine tubular structures but no ovarian tissues were found in them. Thus at least four of these goats were male pseudohermaphrodites.  相似文献   
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