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51.
AIM: To investigate, in a pilot study, a possible genetic component to type 2 diabetes mellitus (T2D) in Burmese cats in New Zealand by analysing pedigree data.

METHODS: Pedigrees were obtained for 305 Burmese cats living in New Zealand; diabetes was diagnosed in 19 of these due to presence of polyuria and polydipsia, persistent concentrations of glucose in plasma >16?mmol/L and glucosuria prior to insulin treatment. Pedigrees were also submitted for 16 cats with no clinical signs of T2D. The remaining 270 cats were unobserved relatives of these individuals. Inbreeding coefficients and heritability were calculated, and a single major locus model segregation analysis was conducted using pedigree analysis software.

RESULTS: Nineteen cats were diagnosed with T2D. Males (n = 14) and females (n = 5) were both affected, suggesting that the gene or genes causing diabetes are autosomal rather than sex-linked. Examination of the pedigree revealed few signs of fully penetrant dominant gene action: diabetes was ostensibly rarely seen in sequential generations and nearly always skipped at least one and often more generations; apparently unaffected offspring of apparently unaffected parents sometimes produced affected progeny. The mean relatedness of the affected animals within the core pedigree (16 diabetic cats) was 0.049, and mean inbreeding 0.033. Based on 100,000 permutations of the trait values, the expected relatedness of a random sample of 16 animals taken from the phenotyped animals would be 0.013 (SD 0.007) (permutation p = 0.0009). The observed inbreeding was also significant (permutation p= 0.02).

Heritability was estimated to be 9 (95% CI = 0–57)% assuming all animals with unknown status were unaffected. The best fitting genetic model was a major gene model with dominant expression with the risk allele frequency at 15% with 60% penetrance.

CONCLUSIONS: In this pilot study the increased inbreeding in the cases, lack of likely sampling bias, the increased frequency of T2D in Burmese, and small number of breed founders are consistent with the involvement of a major locus in diabetes in Burmese cats with a significant risk allele prevalence. However, low case numbers meant this could not be unambiguously confirmed. A genome-wide association study may be useful for investigating the genetic cause of T2D.  相似文献   
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Objective To describe the incidence rate of musculoskeletal (MS) injuries and investigate the factors that influence recovery from MS injury in young Thoroughbred horses in Australia. Methods Training and injury data were collected at fortnightly intervals from 14 trainers in New South Wales. Incidence rates were calculated for initial injuries stratified by age‐class and sex. Survival analysis methods were used to investigate the time to recovery after the first MS injury (measured as a start in a race or barrier trial). Results For the 248 racehorses enrolled, there were 428 injuries recorded; 2‐year‐olds were 2.99‐fold more likely than 3‐year‐olds to sustain an MS injury. The cumulative percentage of horses that had recovered within 6 months was 55%. The time to recovery was longest in horses whose fast gallop speed prior to injury was < 890 m/min. Conclusion This study supports the finding that shin soreness is the most common MS injury in young Australian Thoroughbreds. There was an increased rate of MS injury in 2‐year‐olds compared with 3‐year‐olds. However, it was impossible to determine if the increased risk in 2‐year‐olds was related to age, the start of training or a combination of both. The study also found that horses performing at higher exercise speeds prior to injury were more likely to recover. There was a significant effect of trainer, suggesting that other factors related to trainer may influence the time to the recovery. Additional research is required to understand the determinants of time to recovery.  相似文献   
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BACKGROUND: Phoma stem canker, caused by the coexisting related fungal pathogens Leptosphaeria maculans (Des.) Ces. & de Not and L. biglobosa Shoemaker & H Brun, is a major disease of winter oilseed rape in the UK. Annually, over 90% of UK crops receive at least one foliar application of fungicide, but little is known about the sensitivity of the more damaging L. maculans and the less damaging L. biglobosa to these fungicides. The effects of flusilazole, tebuconazole and Methyl Benzimidazole Carbamate (MBC) fungicides (benomyl and carbendazim) on the germination of ascospores, conidia and germ tube growth of both species were examined. Isolates collected from different oilseed rape crops in England and Wales were assessed for their mycelial growth on fungicide‐amended medium, and ED50 values were calculated. RESULTS: Leptosphaeria maculans and L. biglobosa differed in their sensitivity to fungicides. Conidial germination of L. maculans was more sensitive to these fungicides than that of L. biglobosa. Isolates of L. maculans had smaller ED50 values for mycelial growth for all fungicides tested than isolates of L. biglobosa. CONCLUSION: These results suggest that fungicide applications might affect the structure of L. maculans/L. biglobosa populations in UK winter oilseed rape crops. Copyright © 2009 Society of Chemical Industry  相似文献   
55.
The results of massively parallel three-dimensional molecular dynamics simulations of the perpendicular intersection of extended dislocations in copper are reported. The intersection process, which involves three of the four possible 111 glide planes in the face-centered cubic lattice, begins with junction formation, followed by unzipping, partial dislocation bowing, cutting, and, finally, unit jog formation. The investigation provides insights into this complex atomistic process, which is currently not accessible to experimental investigation.  相似文献   
56.
Small RNA represents several unique non‐coding RNA classes that have important function in a wide range of biological processes including development of germ cells and early embryonic, cell differentiation, cell proliferation and apoptosis in diverse organisms. However, little is known about their expression profiles and effects in yak oocytes maturation and early development. To investigate the function of small RNAs in the maturation process of yak oocyte and early development, two small RNA libraries of oocytes were constructed from germinal vesicle stage (GV) and maturation in vitro to metaphase II‐arrested stage (M II) and then sequenced using small RNA high‐throughput sequencing technology. A total of 9,742,592 and 12,168,523 clean reads were obtained from GV and M II oocytes, respectively. In total, 801 and 1,018 known miRNAs were acquired from GV and M II oocytes, and 75 miRNAs were found to be significantly differentially expressed: 47 miRNAs were upregulated and 28 miRNAs were downregulated in the M II oocytes compared to the GV stage. Among the upregulated miRNAs, miR‐342 has the largest fold change (9.25‐fold). Six highly expressed miRNAs (let‐7i, miR‐10b, miR‐10c, miR‐143, miR‐146b and miR‐148) were validated by real‐time quantitative PCR (RT‐qPCR) and consistent with the sequencing results. Furthermore, the expression patterns of two miRNAs and their potential targets were analysed in different developmental stages of oocytes and early embryos. This study provides the first miRNA profile in the mature process of yak oocyte. Seventy‐five miRNAs are expressed differentially in GV and M II oocytes as well as among different development stages of early embryos, suggesting miRNAs involved in regulating oocyte maturation and early development of yak. These results showed specific miRNAs in yak oocytes had dynamic changes during meiosis. Further functional and mechanistic studies on the miRNAs during meiosis may beneficial to understanding the role of miRNAs on meiotic division.  相似文献   
57.
Pregnancy‐associated glycoproteins (PAG) are secreted by the binucleate giant cells of the ruminant placenta and enter maternal circulation at the time of placental attachment. The IDEXX Milk Pregnancy Test (IDEXX, Westbrook, ME) detects a subset of PAG in milk. Although designed as a management tool for dairy cows, there is potential for using the milk PAG test in beef cows. Our objective was to compare the performance of the milk PAG ELISA with a gold standard method for pregnancy diagnosis and determine the agreement between milk and serum PAG analysis in lactating beef cows. Angus and Angus‐crossed cows (n = 332) from two Michigan beef herds were enrolled in this study. Cows were subjected either to timed artificial insemination followed by exposure to a bull or exclusively exposed to a bull. The bulls and cows were separated 30 days prior to examination. Serum and milk samples were collected and submitted within 24 h of collection to a commercial laboratory for PAG analysis using the IDEXX Milk Pregnancy Assay (milk) and the IDEXX Bovine Pregnancy Assay (serum). Concurrently with milk and serum collection, each cow was examined transrectally by palpation or ultrasonography. When compared to transrectal examination, the performance (and 95% confidence intervals) of the milk PAG ELISA was sensitivity of 99.7% (99.0–100.0%) and specificity of 80.8% (65.6–95.9%). The lower specificity is likely due to the low prevalence (9.9%) of open cows (n = 30) in the herds examined. Of the 332 cows examined, 1.8% (n = 6) were classified as rechecks using the milk PAG ELISA. Results of the milk and serum PAG ELISA were in high agreement (kappa coefficient = 0.91). The milk PAG ELISA was accurate in predicting pregnancy status using milk collected from beef cattle between days 37 and 125 post‐insemination and may be useful for aiding management decisions in beef herds.  相似文献   
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Anthelmintic dose selection by farmers   总被引:1,自引:0,他引:1  
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60.
The vitamin A concentration was determined in 89 Australian brands of commercial foods for dogs and cats. It was found that 8% of the dog foods and 14% of the cat foods had concentrations of vitamin A below the minimum recommended 1.1 mg/kg dry matter (dm) for dogs and 1.8 mg/kg dm for pregnant or lactating cats. Canned and fish-labelled cat foods were the only varieties with less than the minimum recommended concentration of Vitamin A, of which 71% were the same brand. The minimum recommended concentration of vitamin A was exceeded in all canned dog food tested. Concentrations of vitamin A in dry (ca. 6% moisture) dog and cat foods and semi-moist dog foods (ca. 23% moisture) never exceeded 10 mg vitamin A/kg dm. In contrast, canned pet foods stated to contain liver or kidney showed vitamin A concentrations from 13 to 284 mg/kg dm.  相似文献   
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