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1.
Gastrointestinal nematode infections of goats in a sub-tropical and humid zone of India 总被引:1,自引:0,他引:1
Twelve hundred and twenty-eight goats (Capra hircus L.) from a sub-tropical and humid zone of India were examined for gastrointestinal nematodes. The species encountered in the region were: Haemonchus contortus, Bunostomum trigonocephalum, Oesophagostomum columbianum, Trichuris globulosa, O. aspersum, and T. ovis. The overall infection rate was 86.8%. Among various species found, H. contortus emerged as the most prevalent, although B. trigonocephalum and O. columbianum were also significantly in evidence. The seasonal fluctuation in infection was assessed by monitoring the faecal egg count of 1638 goats slaughtered during the 1-year period. The maximum values for the prevalence and overall mean eggs g-1 of faeces (EPG) were observed after the heavy rainfall season and remained at a relatively high level from July to December. H. contortus and O. columbianum appear to be of major importance as parasites in the goats of this climatic zone; the role of climatic factors in their prevalence is discussed. 相似文献
2.
Identification of internal control genes in milk‐derived mammary epithelial cells during lactation cycle of Indian zebu cow
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3.
Tappeiner Ulrike Leitinger Georg Zariņa Anita Bürgi Matthias 《Landscape Ecology》2021,36(8):2317-2328
Landscape Ecology - Landscape ecology early on developed the awareness that central objects of investigation are not stable over time and therefore the historical dimension must be included, or at... 相似文献
4.
The golden shiner, Notemigonus crysoleucas, is a major bait and forage fish species in the USA. Farmers produce millions of golden shiners annually that are distributed live, many across state boundaries. Native over much of the eastern and central USA, this species is often present but rarely abundant in natural systems, as fish density is apparently controlled by predation rather than by food resources. Aquaculture of the golden shiner is a century‐old practice and culture methods have evolved over time, resulting in today's farm‐raised, certified specific pathogen– and aquatic nuisance species–free baitfish. Federal and state agencies and universities have a long history of developing culture methods and promoting baitfish culture to replace the indiscriminate and wasteful harvest of fish from natural waters. Despite advances in culture methods and the advantages of a farm‐raised species produced under controlled and biosecure conditions, golden shiner farming is only marginally profitable and remaining farmers survive on farm equity and increased market share from others exiting the business. Ironically, increasing regulations and restrictions leading to a reduction in the supply of farm‐raised baitfish could drive anglers back to harvesting bait from natural waters, the very concern that initiated government support for baitfish culture a century ago. 相似文献
5.
Anita Sønsteby Arnfinn Nes Finn Måge 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):128-134
The effects of bark mulch and NPK fertilizers on yield and leaf and soil nutrient status of ‘Korona’ strawberry plants (Fragaria×ananassa Duch.), were studied over a period of three years. A significant effect of mulching was found in the first harvest year, but additional fertilizer did not affect total yield. Bark mulch slightly decreased the level of leaf nitrogen, but increased the level of leaf phosphorus and potassium in all years. Bark had a significant, negative effect on soil nitrate and ammonium content in the two first seasons. Mulching increased the soil moisture content in all years. 相似文献
6.
Grobler DG Michel AL De Klerk LM Bengis RG 《The Onderstepoort journal of veterinary research》2002,69(3):221-227
A survey to determine the bovine tuberculosis status of buffalo herds north of the Olifants River in the Kruger National Park was conducted, using a new diagnostic approach. Diagnosis of Mycobacterium bovis infection was accomplished using the gamma-interferon assay technique in 608 adult buffaloes out of a total of 29 discreet herds. The animals were immobilized in groups of 10-15, bled, individually marked and then revived and released on site. As soon as test results were available (after 26-36 h), the same buffalo herd was relocated by tracking the frequency of a radio-collar previously fitted to one adult cow per group during the initial operation. Bovine reactors were identified, darted and euthanased from the helicopter. Necropsy and culture findings of all culled buffaloes showed excellent correlation with the results of the ante-mortem gamma-interferon test. The survey revealed that over and above the two positive herds that had been identified during a previous survey carried out in 1996, there were three additional, but previously unidentified, infected herds in the region north of the Olifants River. 相似文献
7.
Michael J Mauel Debra L Miller Anita L Merrill 《Journal of zoo and wildlife medicine》2007,38(3):420-424
Tilapia are cultured worldwide and are increasing in popularity among aquaculturalists in the United States; however, data regarding normal health parameters are limited. Few hematologic and plasma biochemical values of clinically normal tilapia have been reported, but these data may be key for identifying and managing disease issues in recirculating systems. Therefore, blood was collected from clinically normal hybrid tilapia (Oreochromis aureus x Oreochromis nilotica) housed in recirculating systems for the purpose of establishing normal hematologic and plasma biochemical reference ranges. Using standard clinical techniques the following hematologic values were determined: packed cell volume, plasma protein, leukocyte counts, leukocyte differentials, and thrombocyte counts. Additionally, the following plasma biochemical values were determined: albumin, total protein, globulins, albumin/globulin ratio, aspartate aminotransferase, alkaline phosphatase, glucose, uric acid, calcium, phosphorus, magnesium, sodium, potassium, chloride, urea nitrogen, and creatinine. The condition of the sample was also noted (lipemic, hemolysis, and icterus). The reference ranges reported in this study can be used in the management of cultured tilapia in recirculating systems. 相似文献
8.
Dryland sustainable agriculture in the arid zone of India depends upon the choice of suitable cultivars for pure and mixed crop stands. Field experiments were conducted for two years to examine the response of two contrasting cultivars each of pearl millet (Pennisetum glaucum) and clusterbean (Cyamopsis tetragonoloba) in pure stands and in mixed pearl millet‐clusterbean stands. The differential response of cultivars of both crops to pure and mixed stands resulted in a significant genotype × cropping system interaction. Reduction in seed yield of both clusterbean cultivars was greater in mixed stands with tall and long duration pearl millet MH 179 than with medium statured and early maturing HHB 67. The degree of reduction was greater in Naveen, the branched clusterbean cultivar, than in RGC 197, the single stemmed cultivar. Mixing of pearl millet HHB 67 with medium duration clusterbean cultivar Naveen produced maximum pearl millet equivalent total yield. Higher land equivalent ratios (LERs) were also observed when clusterbean cultivars were mixed with early maturing and short statured pearl millet HHB 67. 相似文献
9.
Genetic diseases of sheep and goats 总被引:2,自引:0,他引:2
Congenital malformations and inherited disorders constitute a substantial proportion of the afflictions seen in sheep and goats. Of these, malformations tend to be similar in both species, whereas the genetic diseases encountered to date, with the exception of a few, are different. Of the 28 genetic diseases of sheep and goats described in this review, 60% and 62.5%, respectively, are monogenic disorders. For a majority of the monogenic recessive disorders encountered in these species, the carrier state is not detectable at present, whereas in others, in which a biochemical lesion is known (dermatosparaxis, erythrocyte glutathione deficiency, globoid cell leukodystrophy and glycogen storage disease), the carrier state is detectable with the aid of enzyme and surface protein markers. The latter group and the dominant disorders (anury, cataract, glomerulonephritis, and lethal grey in sheep; gynecomastia and anotia-microtia complex in goats) are easy to eliminate through selective breeding. The polygenic disorders (entropion, epidermolysis bullosa, hereditary chondrodysplasia, and muscular dystrophy of sheep, and udder problems in goats) are more difficult to eradicate, because the mutant genes responsible for these traits generally do not declare themselves until inbreeding brings together a critical concentration to create a health crisis in some, whereas others, which are only short of a few of these mutant genes, might go totally unaffected and therefore undetected. Chromosome defects of the structural nature (translocations) seen in sheep and goats generally create meiotic disturbances, which in a majority of cases lead to subfertility, whereas sex chromosome aneuploids are generally sterile.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
AbstractThis study examined the performance of mechanically graded timber in bending when exposed to fire at various load
ratios. The test specimens were 150 pieces, each with the dimensions of 60 × 120 × 3500mm. The modulus of elasticity (MOE)
of 150 specimens was measured, and 60 among them were selected to formulate the prediction equation for MOE and modulus of
rupture (MOR), which was used to predict the remaining 90 specimens. These were tested under fire exposure in bending using
three-point loading at 11.1%, 16.7%, 33.3%, 66.7%, and 83.3% of the ultimate load. Using mechanically graded timber, which
means acknowledging the actual strength of the bending member, permits fairly precise application to the targeted design load.
This research confirmed that mechanically graded timber under fire exposure has the following tendencies: under the same load
ratio, time to failure is independent of strength class, and, at any load ratio, the critical strength is dependent on the
timber strength class. The obtained design bending strength under fire exposure using the reduced cross section method and
the reduced strength method conformed to those calculated based on Eurocode 5. Following those findings, mechanically graded
timber can be applied to obtain the design bending strength when taking into account the fire attack. 相似文献