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ABSTRACT

Aims: To determine if an ELISA for measurement of IgA in equine serum could be used to measure concentrations of IgA in foal faeces and to determine correlations with concentrations in the milk of the dam.

Methods: Faeces from 20 Welsh Cob and Welsh Pony foals and milk from their dams were collected within 12?hours (Day 0) and at 6 days after parturition (Day 6). On Day 6, faeces could not be collected from 2/20 foals, and milk samples could not be collected from 3/20 mares. An equine IgA ELISA validated for serum and plasma was used to measure concentrations of IgA in all samples in triplicate. The precision of the assay for each sample type was determined using modified CV.

Results: IgA was not detectable in 7/20 Day 0 faecal samples and in 2/18 Day 6 faecal samples. For samples with detectable IgA, the mean modified CV was 10.5 (95% CI?=?6.0–15.0)% for Day 0 faecal samples, and was 6.8 (95% CI?=?4.3–9.4)% for Day 6 faecal samples. Median concentrations of IgA in faeces on Day 0 were lower than concentrations on Day 6 (0.7?mg/g vs. 37?mg/g dry matter; p?=?0.003). Concentrations of IgA in milk and faeces on Day 6 were statistically correlated (r?=?0.59; p?=?0.006).

Conclusions and clinical relevance: The IgA ELISA showed acceptable precision when used to estimate concentrations of IgA in foal faeces during the first week of life, but IgA could not be detected in 37% of meconium samples collected on Day 0. This assay may be useful for investigation of the role of maternal milk IgA in the gastrointestinal tract of neonatal foals, but further assessment of both accuracy and precision of the ELISA is required.  相似文献   
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A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma.  相似文献   
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We investigated the feasibility of enhancing the reproduction of steelhead Oncorhynchus mykiss and landlocked Atlantic salmon Salmo salar in lakes where the consumption of alewives Alosa pseudoharengus and other forage fishes containing thiaminase can cause them to become thiamine deficient and thereby reduce the survival of their fry. We evaluated feeding fingerling steelhead excess thiamine hydrochloride (THC1) for 1 or 2 weeks or equimolar amounts of thiamine mononitrate, thiamine-tetrahydrofurfuryl-disulfide, benfotiamine, or dibenzoyl thiamine (DBT). We found minimal internal reserves of thiamine after 6 months. We also compared the ability of injections of thiamine and its analogs to prevent mortality in thiamine-deficient steelhead and Atlantic salmon sac fry and found all forms to be effective, although benfotiamine was the least effective on an equimolar basis. Further, we injected yearling steelhead and found that DBT was tolerated at approximately 11,200 nmol/g of body weight, about 10 times more than thiamine in any other form. When yearling steelhead were injected with near-maximal doses of thiamine hydrochloride and several analogs and then fed a thiamine-deficient diet, DBT was retained for approximately 2 years--in contrast to other forms, which were retained for less than about 6 months. Therefore, these results suggest that neither feeding nor injecting young hatchery salmonids with DBT is likely to enhance their reproduction for more than 2 years after stocking. However, injecting DBT in nearly mature fish (either cultured fish from hatcheries or wild fish captured in lakes) may provide them with enough thiamine to successfully spawn within 2 years even though they consume mainly thiaminase-containing forage fishes.  相似文献   
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A 5‐year‐old male Miniature Schnauzer was presented with unilateral cryptorchidism and signs of feminization. Abdominal ultrasonography revealed an enlarged right testis and a large, fluid‐filled cavity that appeared to arise from the prostate. Computed tomography revealed the cavity to be consistent with an enlarged uterine body, arising from the prostate, and showed two structures resembling uterine horns that terminated close to the adjacent testes. The dog had a normal male karyotype, 78 XY. Gonadohysterectomy was performed and both the surgical and the histological findings confirmed the presence of a uterus in this male animal, resulting in a diagnosis of persistent Mullerian duct syndrome (PMDS). The enlarged intra‐abdominal testis contained a Sertoli cell tumour. Computed tomography proved to be an excellent diagnostic tool for PMDS.  相似文献   
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BACKGROUND: The potential of systemic neonicotinoid insecticides to control potato leafhopper, Empoasca fabae (Harris), a damaging pest of wine grapes in the eastern United States, was investigated. Soil or foliar applications were made to potted or field‐grown vines, and the response of leafhoppers was determined in clip cages over the following month on young or mature leaves. RESULTS: Foliar application of imidacloprid caused immediate and long‐lasting reductions in E. fabae survival on both leaf ages, whereas the activity of soil‐applied imidacloprid was delayed. Clothianidin, imidacloprid and thiamethoxam all provided long‐lasting reduction in leafhopper survival on young and mature foliage when applied through either delivery route. However, the percentage of moribund nymphs was significantly greater on foliar‐treated vines and increased over time in mature and immature leaves compared with soil‐treated vines. Residue analysis of foliar‐applied imidacloprid showed an 89% decline in mature leaves from day 1 to day 27, and a 98% decline in immature leaves over the same time period. Comparison of soil‐applied clothianidin, imidacloprid and thiamethoxam in field‐grown vines showed significant reduction in E. fabae only on mature leaves of vines treated with thiamethoxam. CONCLUSIONS: Neonicotinoids can control E. fabae in small vines, even in rapidly expanding foliage where this pest causes greatest injury. Soil application provides superior long‐term vine protection because declining residues on foliar‐treated vines lead to suboptimal activity within 2–3 weeks. Vineyard managers of susceptible cultivars may take advantage of this approach to E. fabae management by using foliar applications of the three neonicotinoids tested here, or by using soil‐applied thiamethoxam. Copyright © 2011 Society of Chemical Industry  相似文献   
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The spotted-wing drosophila, Drosophila suzukii Matsumura, is an invasive pest causing significant damage to soft skinned fruits. Control of D. suzukii is critical since there is no tolerance for infested fruit in the market. While most insecticides control one or more D. suzukii life-stages (e.g., egg, larvae, and adult), the impact of insecticides that are toxic to immature stages  is unclear on the subsequent generation of a field population. Insecticides were applied at field recommended rates on cherries and blueberries in the laboratory to determine immature D. suzukii mortality. Spinetoram, cyantraniliprole, malathion, methomyl, spinosad, and phosmet resulted in relatively high mortality of all immature life stages. Zeta-cypermethrin, cyclaniliprole, and fenpropathrin resulted in lower mortality of egg and all larval instars. Malathion was also applied to lowbush blueberries with different fruit sizes (small, medium, and large) in the laboratory and there was no statistical difference in mortality rates depending on fruit sizes. Mortality data from the laboratory experiments were used to parameterize a refined D. suzukii population model. The model revealed that the timing and order of different insecticide classes are important to control D. suzukii population. Model runs that included early applications of more effective insecticides resulted in high immature mortality and greater reduction of D. suzukii populations compared to treatments applied later.

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