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1.
Rupture of the suspensory ligament at the insertions on the proximal sesamoid bones, and of the superficial flexor tendon of the left fore limb, occurred in an adult Angus bull as a result of fighting. There was severe hyperextension of the metacarpophalangeal (MCP) joint with the dewclaws almost touching the ground. Radiographs revealed severe hyper-extension of the MCP joint with the sesamoid bones aligned directly distal to the metacarpus. Initially, a full length fiberglass cast was applied with the limb partially flexed within the cast and the heels elevated. The cast was replaced twice. The cast was removed after 136 days and the bull was bearing full weight on the limb. Prolonged immobilisation of the limb produced new bone in the area (a normal response in cattle) to cause ankylosis of the traumatized MCP joint and partial ankylosis of the carpus. The bull was being used for pasture breeding one year after the injury.  相似文献   
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1. An experiment was conducted to evaluate growth and nutrient efficiency of broiler chicks from 3 to 42 d fed on diets containing alkali‐treated neem (Azadirachta indica A. juss) kernel cake (NKC) as a protein supplement in place of peanut meal (PNM).

2. NKC was treated with sodium hydroxide at 10 (ANKC 1) or 20 g (ANKC 2)/kg and incorporated into the test diets at 135 or 300 g/kg to replace 50 (low—L) or 100 (High—H) % of the PNM protein of the reference diet.

3. Despite comparable retentions of dry matter and total carbohydrate on L‐ANKC 1 and 2, fibre on L‐and H‐ANKC 2 and nitrogen, calcium and acid detergent fibre on all experimental diets compared to the retentions of chicks on the reference diet, only the chicks fed L‐ANKG 2 were found to grow and utilise food as well as those on the reference diet.

4. The activities of serum alkaline phosphatase on H‐ANKC 1 and alanine amino transferase on all test diets were depressed (P < 0.05), but the activity of serum aspartate amino transferase, total erythrocyte count and concentration of blood haemoglobin and urea were similar in all chicks.

5. No significant differences were noticed in the qualitative and quantitative characteristics of the meat of chicks fed on the reference diet and on diets incorporating ANKC at the lower concentrations. Feeding ANKC protein did not impart any untoward taste as evaluated in pressure cooked meat by a semitrained panel on a 7 point Hedonic scale.

6. Except for duodenal and jejunal inflammation in chicks on both reference and test diets, all the vital organs were normal, ruling out any adverse affects caused by residual neem bitters.

7. Comparable performance and cost of chicks fed on the reference and L‐ANKC 2 diets, warrants the utilisation of hitherto wasted protein‐rich NKC after alkali treatment in broiler chick diets to spare peanut meal for human consumption in developing countries.  相似文献   

4.
This study was conducted to identify and analyse the expression of gametogenesis‐associated genes and proteins in foetal and adult buffalo gonads of both the sexes. Relative quantification of the genes was determined by qPCR and Western blotting. Immunohistochemistry was also performed for various gametogenesis‐associated proteins in foetal and adult gonads of both the sexes. We observed significantly (p < 0.05) increased expression of primordial germ cell‐specific, meiotic as well as genes associated with oocyte maturation and development in foetal ovaries as compared to the adult ones. However, significantly (p < 0.05) increased expression of proteins associated with oocyte maturation like GDF9 and ZP4 was found in adult ovaries, indicating temporal regulation of mRNA translation during oogenesis. Meiotic genes showed significantly (p < 0.05) increased expression in adult testes as compared to foetal testes and ovaries, indicating onset of meiosis at a later stage in spermatogenesis. In general, the expression of primordial germ cell‐associated as well as meiotic genes was higher in adult testes, indicating the increased biological activity in the organ. Immunohistochemistry revealed localized expression of gametogenesis‐associated proteins in ovarian follicles and seminiferous tubules of testes, while the surrounding somatic tissues were devoid of these proteins. The study gives an understanding of the sequential and temporal events of gene expression as well as mRNA translation during male and female gametogenesis. It could also be concluded that follicles and seminiferous tubules are the functional units of the female and male gonads, respectively, and their function could be enhanced by appropriate chemical and genetic intervention of the somatic tissue immediately surrounding them. This assumes importance in the context that buffalo attains sexual maturity at an older age of 2–3 years and have smaller ovaries with lesser number of primordial follicles in comparison with cattle, which is suggested to be the main reason of their poor breeding performance.  相似文献   
5.
The objective of this study was to assess the effects of in‐feed chlortetracycline (CTC) as a measure of preventing or minimizing infectious problems of reproductive failure in gilts and sows. In a farm of 400 Large White × Landrace gilts and sows with a clinical history of porcine respiratory and reproductive syndrome (PRRS) virus, the animals were treated with CTC. Treatment consisted of 10 g CTC sow/day for 15 days every 3 months. It improved the health status of sows by decreasing post‐farrowing clinical mastitis and vaginal discharges, abortions, return‐to‐oestrus and irregular return‐to‐oestrus rates. These beneficial effects had a positive impact on the performance of the litter. More piglets were born live and weaned. These positive effects improved with repeated use of CTC. The serological evidence of PRRS virus, Leptospira spp. and Chlamydia spp. and the subsequent beneficial use of the antimicrobial agent indicate that reproductive failure, possibly resulting from the bacterial agents can be controlled with in‐feed use of broad spectrum antimicrobials.  相似文献   
6.
SUMMARY Big liver and spleen disease (BLS) was reproduced experimentally by intravenous (IV) and oral (PO) administration of BLS inocula to susceptible broiler breeder hens 34 to 36 weeks of age. Serological and pathological signs of BLS similar to those seen in the natural disease occurred in inoculated and in-contact birds. Splenomegaly was the earliest and often the only necropsy finding, with hepatomegaly and kidney enlargement occurring in some birds later in the course of the disease. After IV administration, serum antigen was detected between 2 and 4 weeks, and antibody between 3 and 5 weeks. After PO administration, antigen was detected between 2 and 4 weeks, and antibody between 3 and 6 weeks. Antibody persisted in all birds to the end of the experiment (6 weeks), and horizontal transmission probably occurred since in-contact birds developed BLS. Liver probably contained the highest concentration of BLS agent because it had the highest infectivity.  相似文献   
7.
Artificial breeding of mithun poses several challenges including lack of standard protocol for cryopreservation of spermatozoa. This is further complicated by harmful effects of hen's egg yolk (EY) as additive in extender. Purified low‐density lipoproteins (LDL) extracted from EY have been shown as beneficial over EY extender for long‐term semen storage in several species. This investigation explored use of LDL versus EY on semen quality and oxidative stress following freezing–thawing of spermatozoa. A total of 25 of 50 ejaculates based on biophysical parameters were selected for the experiment. After diluting with the Tris‐citrate‐glycerol (TCG) extender, each sample was split into three equal aliquots: Group I, control, EY; Group II and Group III contained 8% and 10% purified LDL, respectively. Frozen–thawed samples were evaluated for motility parameters (progressive, and in the bovine cervical mucus penetration test [BCMPT]), viability, sperm and nuclear abnormality, acrosome integrity, and enzymatic (leakage of intracellular contents) and biochemical (oxidative stress) profiles and in vitro fertility (IVF) assay. Study revealed a significant (< .05) improvement in viability, sperm and nuclear abnormality, acrosome integrity, motility (progressive and in cervical mucus), cholesterol content, and reduction in the leakage of intracellular enzymes in Group II. Moreover, intactness of acrosome and biochemical membranes was protected significantly (p < .05) in addition to significant (p < .05) improvement in binding per cent and binding index in IVF assay in extender containing 8% LDL. These results demonstrate that although cryopreservation of mithun's spermatozoa in EY was comparable with other species, addition of 8% LDL holds a clear advantage over EY or 10% LDL.  相似文献   
8.
Asian rice gall midge (Orseolia oryzae) is a major pest across much of south and southeast Asia. This pest is genetically diverse and many gall midge biotypes are known to exist in each country. During the last three decades, host plant resistance has proved to be the most effective mechanism of controlling the Asian rice gall midge. Seven genes conditioning resistance to gall midge larvae have been identified in rice (Oryza sativa) and are being used in cultivar improvement programs. However, some of these genes are rendered ineffective by new gall midge biotypes. Increased understanding of genetics, inheritance, allelic relationships and linkage is necessary to maximise the durability of major gene resistance by the pyramiding of these genes. The two genes, Gm-2 and Gm-6(t), are known to confer resistance against a number of biotypes in India and China, respectively. An F3 population derived from a cross between Duokang #1 (donor of Gm-6(t)) and Phalguna (donor of Gm-2) was screened against Chinese gall midge biotype 4 at Guangdong, China, and Indian gall midge biotype 1 at Raipur, India. At each location, separately,a single gene governed resistance. The parallel segregation of 417 F3progenies for both biotypes at two locations revealed that recombination had occurred between the two genes, establishing that the two genes are not allelic. However, the two genes Gm-2 and Gm-6(t), were found to be linked with a distance of ∼16.3 cM. A number of lines homozygous at one locus and segregating for the other locus were identified and selected. These lines were selfed to obtain lines homozygous for the favourable alleles at both loci (two locus pyramids). This is the first report on use of conventional host-pest interaction method for pyramiding two closely located Gm-resistance loci of dissimilar effects. The implications of deployment of these pyramids within and across country borders, with reference to the prevailing gall midge populations are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
9.
不同年代大豆品种(系)根系生长动态的比较研究   总被引:1,自引:0,他引:1  
不同年代大豆品种根干重积累动态可以用Logistic曲线方程进行模拟。在不同施肥水平下,根干重最大增长速率及出现的时间和平均增长速率有所不同。根干重最大增长速率出现的时间,中国当代品种、美国当代品种及中国20世纪20年代的品种间差异不显著,各品种间差异及施肥处理间差异也不显著。根干重最大增长速率,中国当代、美国当代及中国20世纪20年代的品种间差异不显著,各品种间差异也不显著,施肥处理间差异显著。平均增长速率,中国当代、美国当代及中国20年代的品种间差异显著,各品种间及施肥处理间差异也显著。不同施肥水平、不同生育时期,中国当代品种与美国当代品种根干重都比中国20年代品种大。  相似文献   
10.
The objective of this study was to investigate the effect of newly developed soya milk Tris (SMT)‐based phytoextender as an alternative to egg yolk Tris (EYT) extender used for cryopreservation of buffalo (Bubalus bubalis) spermatozoa on apoptosis. Fresh buffalo semen (control without dilution) was cryopreserved in conventional EYT (20% egg yolk v/v in Tris) and SMT (25% soya milk v/v in Tris) extender and used for the assessment of expression of apoptotic proteins. Proteins extracted from a total number of nine ejaculates from three individual buffalo bulls chosen at random were separated using SDS–PAGE followed by immunoblotting against caspase‐8, caspase‐9, caspase‐3, poly(ADP‐ribose)polymerase (PARP), cytochrome c and apoptosis inducing factor (AIF). In addition, fluorescence microscopy was used for the detection of mitochondrial membrane potential (JC‐1 assay) and apoptotic cells (annexin V‐FITC/PI assay). The results obtained clearly indicate the significant (p < 0.05) reduction in the expression of caspase‐3 (27 kDa), caspase‐8 (53 kDa), caspase‐9 (50 kDa) precursor and cytochrome c (17 kDa) in semen cryopreserved in SMT extender in comparison with EYT extender. A non‐significant (p > 0.05) reduction in expression of PARP‐DNA‐binding subunit (24 kDa) was observed in SMT extender. No expression of AIF was found in cryopreserved semen samples. A significant (p < 0.05) increase in the mean percentage of cells having high mitochondrial membrane potential and a non‐significant (p > 0.05) decrease in late apoptotic cells (AN+/PI+) was observed in SMT extender when compared to EYT extender. The results demonstrated that cryopreservation of buffalo semen in SMT‐based phytoextender can replace the traditional egg yolk extenders as it reduces the expression of apoptotic proteins maintaining high mitochondrial membrane potential and gives better protection to sperms in terms of its non‐animal origin.  相似文献   
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