Estimation of sensitivity and specificity of pregnancy diagnosis using transrectal ultrasonography and ELISA for pregnancy-associated glycoprotein in dairy cows using a Bayesian latent class model     

RW Shephard  JM Morton 《New Zealand veterinary journal》2018,66(1):30-36

AIMS: To determine the sensitivity (Se) and specificity (Sp) of pregnancy diagnosis using transrectal ultrasonography and an ELISA for pregnancy-associated glycoprotein (PAG) in milk, in lactating dairy cows in seasonally calving herds approximately 85–100 days after the start of the herd’s breeding period.

METHODS: Paired results were used from pregnancy diagnosis using transrectal ultrasonography and ELISA for PAG in milk carried out approximately 85 and 100 days after the start of the breeding period, respectively, from 879 cows from four herds in Victoria, Australia. A Bayesian latent class model was used to estimate the proportion of cows pregnant, the Se and Sp of each test, and covariances between test results in pregnant and non-pregnant cows. Prior probability estimates were defined using beta distributions for the expected proportion of cows pregnant, Se and Sp for each test, and covariances between tests. Markov Chain Monte Carlo iterations identified posterior distributions for each of the unknown variables. Posterior distributions for each parameter were described using medians and 95% probability (i.e. credible) intervals (PrI). The posterior median estimates for Se and Sp for each test were used to estimate positive predictive and negative predictive values across a range of pregnancy proportions.

RESULTS: The estimate for proportion pregnant was 0.524 (95% PrI?=?0.485–0.562). For pregnancy diagnosis using transrectal ultrasonography, Se and Sp were 0.939 (95% PrI?=?0.890–0.974) and 0.943 (95% PrI?=?0.885–0.984), respectively; for ELISA, Se and Sp were 0.963 (95% PrI?=?0.919–0.990) and 0.870 (95% PrI?=?0.806–0.931), respectively. The estimated covariance between test results was 0.033 (95% PrI?=?0.008–0.046) and 0.035 (95% PrI?=?0.018–0.078) for pregnant and non-pregnant cows, respectively. Pregnancy diagnosis results using transrectal ultrasonography had a higher positive predictive value but lower negative predictive value than results from the ELISA across the range of pregnancy proportions assessed.

CONCLUSIONS AND CLINICAL RELEVANCE: Pregnancy diagnosis using transrectal ultrasonography and ELISA for PAG in milk had similar Se but differed in predictive values. Pregnancy diagnosis in seasonally calving herds around 85–100 days after the start of the breeding period using the ELISA is expected to result in a higher negative predictive value but lower positive predictive value than pregnancy diagnosis using transrectal ultrasonography. Thus, with the ELISA, a higher proportion of the cows with negative results will be non-pregnant, relative to results from transrectal ultrasonography, but a lower proportion of cows with positive results will be pregnant.  相似文献   

Atypical scrapie in Australia          下载免费PDF全文

RW Cook  J Bingham  AS Besier  CL Bayley  M Hawes  PL Shearer  M Yamada  J Bergfeld  DT Williams  DJ Middleton 《Australian veterinary journal》2016,94(12):452-455

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Wintersweet (Chimonanthus praecox) toxicity in four goats     

RW Numan  SS Ackermann  JS Shelgren 《New Zealand veterinary journal》2016,64(3):179-181

CASE HISTORY: A one-year-old female goat presented with acute onset of recumbency, seizures and vocalisation approximately 5 hours after being given access to branch trimmings from a neighbour's garden. The plant from which the pruned branches came was subsequently identified as wintersweet (Chimonanthus praecox). Three other goats kept in the same paddock displayed similar clinical signs over a period of 4 hours following the initial presentation.

CLINICAL FINDINGS: All four goats were ataxic, displayed tetanic seizures and were in lateral recumbency; they had dilated pupils and were hyperaesthetic, with elevated heart and respiratory rates. After symptomatic treatment, including sedation with diazepam, one of the three goats continued to deteriorate and was subjected to euthanasia. The remaining three goats recovered over 1–14 days with nursing care and physiotherapy.

DIAGNOSIS: Toxicity due to ingestion of wintersweet, which contains the alkaloid calycanthine.

CLINICAL RELEVANCE: Calycanthine is a central nervous system toxin, causing convulsions. Wintersweet shrubs are present in many New Zealand gardens. Practitioners should be aware that the seeds and flowers, and possibly the leaves, of this plant are highly toxic with signs of toxicity including ataxia, hyperaesthesia and seizures.  相似文献   

Chondrodysplasia in Australian Dexter cattle   总被引：1，自引：0，他引：1  

PAW HARPER  MR LATTER  FW NICHOLAS  RW COOK  PA GILL 《Australian veterinary journal》1998,76(3):199-202

Objective To describe the occurrence of chondrodysplasia in Australian Dexter cattle.
Design A pathological and genetic case report.
Procedure Congenital lethal chondrodysplasia was studied in two female Dexter foetuses aborted mid to late gestation. Clinicopathological findings including histological changes in limb bones, and analysis of pedigree information were evaluated.
Results Characteristic features of congenital lethal chon-drodysplasia (Dexter bulldog) include abortion, disproportionate dwarfism, a short vertebral column, marked micromelia, a relatively large head with retruded muzzle, cleft palate and protruding tongue and a large abdominal hernia. Histological changes in limb bones are consistent with failure of endochondral ossification. Dexter chondrodysplasia is considered to be inherited in an incompletely dominant manner with the homozygous form producing the congenital lethal condition. A preliminary minimum estimate of heterozy-gote frequency is 19% within the registered Australian Dexter herd, based on analysis of the contribution of three obligate heterozygotes whose semen has been widely used by artificial insemination in Australia.
Conclusion Dexter chondrodysplasia is present in Australian cattle and further cases of the homozygous form, congenital lethal chondrodysplasia, are likely to occur.
Recommendation It is requested that spleen and liver tissue from bulldog foetuses and blood from their parents be collected to assist research into Dexter chondrodysplasia.  相似文献   

Evaluation of vaccination strategies against infection with feline immunodeficiency virus (FIV) based on recombinant viral vectors expressing FIV Rev and OrfA     

Huisman W  Schrauwen EJ  Tijhaar E  Süzer Y  Pas SD  van Amerongen G  Sutter G  Rimmelzwaan GF  Osterhaus AD 《Veterinary immunology and immunopathology》2008,126(3-4):332-338

In recent years it has become clear that cell-mediated immunity is playing a role in the control of lentivirus infections. In particular, cytotoxic T lymphocyte responses have been associated with improved outcome of infection, especially those directed against the regulatory proteins like Rev and Tat, which are expressed early after infection. Therefore, there is considerable interest in lentiviral vaccine candidates that can induce these types of immune responses. In the present study, we describe the construction and characterisation of expression vectors based on recombinant Semliki Forest virus system and modified vaccinia virus Ankara for the expression of feline immunodeficiency virus (FIV) accessory proteins Rev and OrfA. These recombinant viral vectors were used to immunize cats using a prime-boost regimen and the protective efficacy of this vaccination strategy was assessed after challenge infection of immunized cats with FIV.  相似文献   

Effect of a prolonged low-dose lipopolysaccharide infusion on feed intake and metabolism in heifers.     

M Steiger  M Senn  G Altreuther  D Werling  F Sutter  M Kreuzer  W Langhans 《Journal of animal science》1999,77(9):2523-2532

Prolonged infusions of bacterial lipopolysaccharides (LPS) are known to model gram-negative bacterial infections, but the basic mechanisms of the LPS effects on feed intake and metabolism and their potential interdependence are largely unknown. The aim of the present study was to distinguish and to better characterize the feeding suppressive and metabolic effects of LPS. Six heifers were infused intravenously for 100 min with either 1) LPS (2 microg/kg BW) with free access to feed, 2) saline with free access to feed, or 3) saline with feeding restricted to the amount of feed consumed after LPS infusion. Feed intake, body temperature, plasma concentrations of various metabolites and hormones, and the respiratory quotient and heat production were measured. The LPS reduced feed intake and induced pronounced changes in metabolic energy turnover and fat and carbohydrate metabolism that were largely independent of the concomitant feed intake reduction. Some of the metabolic changes were biphasic; the first phase resembled a stress response with increases in plasma glucose and cortisol, and the second phase reflected a beginning energy deficit with low plasma glucose and enhanced lipolysis. The coincidence of a short-term surge of plasma insulin with marked transient decreases in plasma FFA, glycerol, and beta-hydroxybutyrate as well as with the transition from hyper- to hypoglycemia indicates that insulin plays a role in some of the metabolic responses to LPS. The failure of LPS to clearly increase energy expenditure despite the increase in body temperature suggests that anaerobic mechanisms of heat production and, perhaps, a reduced peripheral blood flow contributed to the fever. Many of the initial metabolic responses occurred before and, therefore, independent of, an increase in circulating tumor necrosis factor-alpha.  相似文献   

Influence of plant lecithin partly replacing rumen-protected fat on digestion, metabolic traits and performance of dairy cows     

H.-R. Wettstein  M. G. Quarella Forni  M. Kreuzer  F. Sutter 《Journal of animal physiology and animal nutrition》2000,84(5):165-177

Nutrient digestibility, metabolic effects and performance were evaluated in lactating cows (n = 6 × 6) receiving diets containing one of four different lecithins (raw, deoiled and deoiled/partially hydrolysed soy lecithin, raw canola lecithin) or soybean oil in combination with Ca soaps of palm oil fatty acids in a ratio of 1 : 3. A diet supplemented only with Ca soaps served as a control. The complete diets consisted of forage and concentrate (0.62 : 0.38) and total lipid supplementation was 30 g fatty acids/kg dietary dry matter. Lecithins had no effect on milk yield and milk composition. Apparent digestibility of dry matter, organic matter and gross energy were highest in the control diet and lowest in the soybean oil diet (p < 0.1) with intermediate values for the lecithin‐supplemented diets. Soybean oil particularly reduced fibre digestibility (significant with hemicellulose), whereas this effect was reduced or even missing when lecithins, particularly raw canola lecithin and deoiled/hydrolysed soy lecithin, were used. The digestibility of total fatty acids was not affected by the treatments. The effects were also not significant for blood plasma traits except for insulin which was significantly higher with raw than with deoiled/hydrolysed soy lecithin. In conclusion, lecithins, particularly those technologically modified or of a low polyenoic fatty acid content, might be preferred to oils when used as an energy source whereas they failed to improve digestibility of rumen‐protected fats.  相似文献   

Lactational and metabolic effects in cows of lysine and methionine added to a ration deficient according to the I.N.R.A. method.     

T F Kr?ber  M Kreuzer  M Senn  W Langhans  F Sutter 《Archives of Animal Nutrition》2000,53(4):375-394

The effects of adding lysine and/or methionine to a ration of calculated deficiency in these amino acids of 10% and 20%, respectively, were studied in 24 Brown Swiss cows. The mixed rations (27% grass silage, 19% maize silage, 5% hay and 49% concentrate on DM basis) contained 14.5% CP on average. Lysine supply was selectively elevated by adding fish meal in exchange for other concentrate ingredients. Methionine was supplied in a rumen-protected form. Milk protein content was elevated whereas fat amount decreased by adding both amino acids. Lactose content increased without additional lysine from fish meal. Live weight, milk yield, milk fat content and protein amount remained unaffected by any variation of amino acids supply. Also nutrient digestibility and nitrogen balance were not changed by the treatments. Blood plasma concentrations confirmed the assumed variation in metabolic lysine and, less clear, methionine supply. Effects on plasma concentrations of other amino acids were relatively small. Most plasma hormones and enzymes, and metabolites in plasma, urine and milk did not respond to the variation in amino acid supply. Lysine addition via fish meal increased aspartate amino transferase and decreased urinary allantoin concentration. Additional methionine elevated plasma ornithine. Overall lysine and methionine appear to have been only marginally deficient in the unsupplemented ration fed for 3 weeks despite the deficiency of 10% to 20% as calculated by the I.N.R.A. method.  相似文献   

Skeletal Size and Shape Diversity in the Horse     

E.T. Chu  J.J. Allen  C.L. Streeter  N.B. Sutter  S.A. Brooks 《Journal of Equine Veterinary Science》2009

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Affirmative action policies promote women and do not harm efficiency in the laboratory     

Balafoutas L  Sutter M 《Science (New York, N.Y.)》2012,335(6068):579-582

Gender differences in choosing to enter competitions are one source of unequal labor market outcomes concerning wages and promotions. Given that studying the effects of policy interventions to support women is difficult with field data because of measurement problems and potential lack of control, we evaluated, in a set of controlled laboratory experiments, four interventions: quotas, where one of two winners of a competition must be female; two variants of preferential treatment, where a fixed increment is added to women's performance; and repetition of the competition, where a second competition takes place if no woman is among the winners. Compared with no intervention, all interventions encourage women to enter competitions more often, and performance is at least equally good, both during and after the competition.  相似文献