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排序方式: 共有290条查询结果,搜索用时 218 毫秒
1.
DNA fingerprinting with the probes 33.15 and alpha-globin 3'HVR has been used to resolve three cases of disputed paternity in dogs. For each pedigree it was necessary to establish which bands in the DNA fingerprints of the offspring were of paternal origin, and then establish which putative sire carried all these bands. In the first case, a litter of Rhodesian Ridgebacks, twelve DNA bands were informative in establishing paternity. In the second case, a litter of Afghan hounds, five DNA bands established paternity, Lastly, in a litter of Border collies, five DNA bands established paternity. In each case a single dog only sired the entire litter. 相似文献
2.
Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm 下载免费PDF全文
EA Lane MLJ Bijnen M Osborne SJ More ISF Henderson P Duffy MA Crowe 《Reproduction in domestic animals》2016,51(2):181-187
To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4–15 years) had bred 2385 mares (mean age 9.4 years; range 3–24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk‐in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post‐partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting. 相似文献
3.
N. R. Atkinson S. D. Young A. M. Tye N. Breward E. H. Bailey 《Soil Use and Management》2012,28(4):559-570
Urban waste disposal occurred on fenland to the west of Manchester, England, between 1900 and 1964. The reclaimed fenland, Chat Moss, is now used for mixed arable farming. A total of 1.92 Mt of waste including privy midden, street sweepings, clinkers and slaughterhouse refuse was incorporated into the moss resulting in a modified topsoil with raised pH and reduced organic matter content compared with the subsoil. Elevated levels of potentially toxic elements (PTEs) are observed in the topsoil beyond the typical depth of atmospheric contamination; Cd and As concentrations exceed soil guideline values (SGVs) at 1.8 and 43 mg/kg, respectively. Sequential extraction indicates that waste‐derived Pb, Zn and Ni remain predominantly in the residual fraction, whereas Cu was mainly organically bound. Arsenic was predominately found in oxide and organic matter fractions with Cd in carbonate, oxide, organic matter and residual fractions. Pot trials indicated limited uptake of PTEs by vegetables grown on the waste‐amended soil, with the exception of Cd uptake by lettuce (0.22 mg/kg FW) and Pb uptake by radish (0.16 mg/kg FW), which exceeded current EU limits of 0.2 and 0.1 mg/kg FW, respectively. Hazard quotients (HQs) identified no risks to adults from consumption of vegetables grown in these soils with the exception of lettuce consumption with a HQ of 1.4. Risks to children were slightly greater with HQs >1 for Cd in lettuce, spinach, carrots and onion, As in lettuce, parsley and onion and for Zn in spinach. 相似文献
4.
Kim E. Hammond-Kosack Howard J. Atkinson Dianna J. Bowles 《Physiological and Molecular Plant Pathology》1989,35(6)
Systemic changes in gene expression have been analysed in potato plants following root infection with the cyst nematode Globodera rostochiensis. Root invasion by the pathogen induced major changes to occur in the composition of proteins extracted in intercellular fluid from the leaf apoplastic space. The changes involved the disappearance of innate leaf proteins and the accumulation of novel gene products. Analysis by SDS-PAGE indicated that the leaf polypeptides induced on nematode invasion are not cultivar or nematode pathotype-specific. Aspirin treatment of leaves induced a similar pattern to that induced systemically by nematodes, but several gene products were specific for the latter method of induction. In particular, two abundant [125I]-Con A binding polypeptides of high Mr accumulated in intercellular fluid only on aspirin treatment. The results are discussed in the context of the role of the extracellular leaf proteins and their modulation by systemic signals. 相似文献
5.
Allan E. Atkinson Matthew D. Weitzman Louis Obosi David J. Beadle Linda A. King 《Pest management science》1990,28(2):215-224
Recombinant DNA technology has enabled the expression of a large number of eukaryotic genes in vitro. There has been growing interest in recent years in the development of baculovirus expression vectors as an easily manipulated gene expression system. Both virus and insect cell culture are relatively easy to handle, and biologically active proteins have been produced abundantly from a variety of eukaryotic, prokaryotic and viral genes. This review describes the molecular biology of baculoviruses and some of the current applications of the baculovirus expression system in insect cells. Specific emphasis is placed on those features relevant to the use of this system in pesticide research. 相似文献
6.
The effects of vaccination of Merino ewes with an attenuated Australian bluetongue virus serotype 23 at different stages of gestation 总被引:1,自引:0,他引:1
SUMMARY A cell culture attenuated Australian bluetongue virus serotype 23 (BLU23) prototype vaccine was assessed for its effects on pregnant Merino sheep. Seventy-six ewes were vaccinated at 5 different stages of gestation, and the failure to lamb at term was as follows: 35 to 43 days of gestation, 20/36 (56%); 57 to 64 days of gestation, 3/10 (30%); 81 to 88 days of gestation, 3/10 (30%); 109 to 116 days of gestation, 0/10 (0%); 130 to 137 days of gestation, 0/10 (0%). Of 30 ewes vaccinated with a cell culture supernatant fluid control between 35 and 43 days of gestation, 6.7% (2/30) failed to lamb at term. Two ewes vaccinated with BLU23 vaccine between 35 and 43 days of gestation had lambs with hydranencephaly. All other lambs born were clinically normal. Three ewes vaccinated with BLU23 aborted. Two of these were vaccinated between 35 and 43 days of gestation, the 3rd between 81 and 88 days of gestation. Five lambs were born with BLU group antibody. Four of these were from ewes vaccinated between 35 and 43 days of gestation, and 2 of these had hydranencephaly. The fifth was from a ewe vaccinated between 57 and 64 days of gestation. The vaccine did not produce disease in adult sheep, but was a potent cause of early foetal death and to a much lesser extent foetal malformation. 相似文献
7.
8.
Atkinson RA Cook RW Reddacliff LA Rothwell J Broady KW Harper P Ellis JT 《Australian veterinary journal》2000,78(4):262-266
OBJECTIVE: To investigate the seroprevalence of Neospora caninum infection in a commercial dairy cattle herd, 15 months after detection of an abortion outbreak. PROCEDURE: Sera from the whole herd (n = 266) were examined for N caninum antibodies by indirect fluorescent antibody test (IFAT) and immunoblot analysis. Herd records were reviewed to collate serological results with abortion history, proximity to calving, and pedigree data. RESULTS: The seroprevalence of N caninum infection was 24% (63/266) for IFAT titre > or = 160, 29% (78/266) for immunoblot positive (+ve), and 31% (82/266) for IFAT > or = 160 and/or immunoblot +ve; 94% (59/63) of animals with IFAT > or = 160 were immunoblot +ve. The association between seropositivity (IFAT > or = 160 and/or immunoblot +ve) and history of abortion was highly significant (P < 0.001); the seroprevalence was 86% (18/21) in aborting cows, compared with 30% (50/164) in non-aborting animals. The abortion rate for seropositive cows was 26% (18/68) compared with 3% (3/117) for seronegative animals. IFAT titres of infected cows were higher within 2 months of calving than at other times (P < 0.001). The association between seropositivity in dams and daughters was highly significant (P = 0.009). CONCLUSIONS: The abortions were associated with N caninum infection and there was evidence of reactivation of latent infection close to calving and congenital transmission of infection. Immunodominant antigens identified by immunoblots may prove useful for improved diagnostic tests. 相似文献
9.
Steller sea lions (Eumetopias jubatus) rarely strand in areas monitored by humans, and there is little published data on the diseases, parasites, nutritional state, and stress levels of Steller sea lions in the wild. In May 2002, a female Steller sea lion pup (EJS-02-01) was sighted separated from her mother after strong storms in Southeast Alaska. After 5 days of observations, EJS-02-01 was transferred to the Alaska SeaLife Center (ASLC) in Seward, Alaska. During 11 mo of rehabilitation at ASLC, body weight was monitored and opportunistic fecal samples (n = 86) were analyzed for corticosterone concentrations. Fecal corticosterone concentrations ranged from 15 to 3,805 ng/ g for EJS-02-01. Peak corticosterone values reflected responses to acute stressors during rehabilitation. EJS-02-01 was successfully released at Gran Point, Alaska, in April 2003. Fecal corticosterone assay monitoring provided a valuable tool to monitor various stressors and is useful in monitoring long-term situations like rehabilitation. 相似文献
10.
A Rae Gandolf Mark G Papich Amy B Bringardner Mark W Atkinson 《Journal of zoo and wildlife medicine》2006,37(2):145-150
This study describes the pharmacokinetics of enrofloxacin following oral and i.v. administration to goral (Nemorrhaedus goral arnouxianus). The objective of this study was to expand upon current antimicrobial treatment options available for use in goral by measuring plasma concentrations and examining the pharmacokinetics of enrofloxacin in these animals. Two single-dose treatments of enrofloxacin were administered to four goral in a crossover design. Single-dose treatments consisted of administration of injectable enrofloxacin i.v. (5 mg/kg) and enrofloxacin tablets (136 mg chewable tablets) dissolved in a grain slurry and administered p.o. (10 mg/kg). Plasma levels of enrofloxacin and its metabolite ciprofloxacin were measured with the use of high-performance liquid chromatography with UV detection. Plasma volume of distribution for i.v. enrofloxacin was 2.15 - 1.01 L/kg, with a mean elimination half-life of 13.3 hr and total body clearance of 0.19+/-0.14 L/kg/hr. The maximum plasma concentration measured for oral enrofloxacin was 2.77 microg/ml, with a mean half-life of 5.2 hr and systemic availability of 14.6%. The area under the plasma concentration over time curve (AUC) for oral enrofloxacin was 21.06 microg/hr/ml. The area under the plasma concentration over time curve generated for oral enrofloxacin in goral yields an area under the plasma concentration over time curve to minimum inhibitory concentration ratio > 100 for many gram-positive and gram-negative bacterial pathogens common to small ruminants. Based on these results, oral enrofloxacin may be considered for further study as a treatment option for susceptible infections in goral. 相似文献