Variance estimation for population attributable risk in a complex cross-sectional animal health survey     

Wagner BA  Wells SJ  Kott PS 《Preventive veterinary medicine》2001,48(1):1-13

Population attributable risk estimates offer a method of combining information on population exposure and disease risk factors into a single measure. Univariate and multivariable methods exist for calculating point estimates and variances under the assumption of equal sampling probabilities. National Animal Health Monitoring System national studies typically use a complex survey design (where selection probabilities vary by design strata), which makes use of these methods of calculating variance inappropriate. We suggest the use of a method called "delete-a-group" jackknife to estimate the variance of population attributable risk when a complex survey design has been implemented. We demonstrate the method using an example of Johne's disease. Advantages of the "delete-a-group" jackknife method include simplicity of implementation and flexibility to estimate variance for any point estimate of interest.  相似文献   

Mammary cancer in humans and mice: a tutorial for comparative pathology     

Cardiff RD  Wagner U  Hennighausen L 《Veterinary pathology》2001,38(4):357-358

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Secretion of dopamine and norepinephrine in hypophyseal portal blood and prolactin in peripheral blood of Holstein cattle     

Hard DL  Bhatnagar RK  Molina JR  Anderson LL 《Domestic animal endocrinology》2001,20(2):89-100

The objective was to test the hypothesis that dopamine regulates prolactin (PRL) secretion by determining acute changes in catecholamine concentrations in hypophyseal portal blood of cattle, and their relation to peripheral blood concentration of PRL in hypophyseal stalk-transected (HST) and sham-operated controls (SOC). Holstein heifers (606 +/- 21 kg BW; mean +/- SE) were subjected to neurosurgery for 8 h to collect hypophyseal portal blood with a stainless steel cannula designed with a cuff placed under the pituitary stalk and peripheral blood via a jugular vein catheter. PRL plasma concentration was measured by radioimmunoassay, and dopamine and norepinephrine in portal plasma by radioenzymatic assay. During anesthesia before HST or SOC, PRL plasma concentration ranged from 20-40 ng/ml throughout 255 min. PRL abruptly increased and remained above 90 ng/ml after HST compared with a steady decrease to <20 ng/ml in SOC heifers throughout 440 min. Within 5 min after severing the hypophyseal stalk, dopamine in portal blood (>8 ng/ml) was significantly increased (P < 0.05) compared with peripheral blood (<2 ng/ml). Norepinephrine concentration in portal blood was significantly greater (P < 0.05) than in peripheral blood during the first 60 min. The sustained high PRL level in peripheral plasma after severing the hypophyseal stalk stimulated hypothalamic dopamine secretion from hypophyseal portal vessels during the prolonged period of blood collection. Norepinephrine concentration in these cattle was greater in hypophyseal portal than in peripheral blood, implicating both an important hypothalamic source of the catecholamine as well as an adrenal gland contribution during anesthesia.  相似文献   

Preparing the veterinary profession for corporate and trade issues in the Americas: proceedings of a conference on synergism and globalization, Santiago, Chile, May 6-8, 2001     

Brown C  Carbajal I  Wagner G 《Journal of veterinary medical education》2001,28(2):56-61

The complex and rapid-paced development of international trade, coupled with increasing societal demands for the production not only of abundant and inexpensive food, but also of food that is safe and has been raised in a humane and environmentally friendly manner, demands immediate attention from the veterinary community. The new culture of global trade agreements, spurred by the development of the WTO, dictates massive changes and increasing integration of public and private sectors. This is a huge growth area for our profession and will require individuals with a skill set we do not yet provide in our educational framework. In North America, veterinary education is parochial and focused on specialization. This strong orientation toward companion animals fails to provide adequate training for those interested in acquiring the necessary skills for the emerging area of globalization and trade. In South America, curricula are less harmonized with one another and there is tremendous variation in degree programs, rendering it difficult to ascertain whether veterinarians are prepared to assume decision-making responsibilities regarding international transport of food. If we do not begin to prepare our graduates adequately for this emerging market demand, the positions will be filled by other professions. These other professions lack broad-based scientific knowledge about animal physiology and disease causation. Decisions made without adequate background could have devastating consequences for society, including incursions of unwelcome diseases, food safety problems, and public health issues. To prepare our new veterinary graduates for the future and this emerging market, it is important to nurture a global mindset within our academic communities and to promote communications, languages, and an interdependent team mentality. Areas of technical expertise that need a place, perhaps a parallel track, in the curriculum include production medicine, public health, food safety, and international veterinary medicine. The major trade corridors of the future regarding animal-based protein flow between North and South America. It is absolutely essential that we find areas of consensus and deficiencies so that we can harmonize our trade agreements and ensure adequate flow of safe food products from one continent to the other.  相似文献   

Radiographic anatomy of the thoraco-abdominal cavity of the ostrich (Struthio camelus)     

Wagner WM  Kirberger RM  Groenewald HB 《Journal of the South African Veterinary Association》2001,72(4):203-208

This study provides a reference for the radiographic anatomy of the thoraco-abdominal cavity of female ostriches as a representative of ratites. One ostrich cadaver, 2 adult and 2 growing ostriches were used. Right lateral radiographs produced by a 6-frame technique and 2 dorsoventral radiographs produced by an adapted 3-frame technique were selected and schematic illustrations of these were labelled to illustrate normal radiographic anatomy. Differences from other avian species and unique features of the ostrich are briefly discussed.  相似文献   

'Hoja de perejil' (parsley leaf) of tomato and morrenia little leaf, two new diseases associated with a phytoplasma in Bolivia     

P. Jones  Y. Arocha  O. Antesana  E. Montellano  P. Franco 《Plant pathology》2005,54(2):235-235

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First report of an isolate of 'Candidatus Phytoplasma australiense' associated with a yellow leaf roll disease of peach (Prunus persicae) in Bolivia     

P. Jones  Y. Arocha  O. Antesana  E. Montilliano  P. Franco 《Plant pathology》2005,54(4):558-558

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Retroperitoneal perirenal pseudocyst in a Massese breed ram.     

Franco Mutinelli  Marta Vascellari  Eliana Schiavon 《Journal of veterinary diagnostic investigation》2005,17(3):288-290

The macroscopic and microscopic features of a retroperitoneal perirenal pseudocyst in a 12-month-old ram without impairment of renal function are described. In humans and animals, uriniferous pseudocysts may be of traumatic origin, resulting from rupture of kidney, renal pelvis, or ureter, or congenital. Lymphatic pseudocysts may develop secondary to inflammatory obstruction of the hilar lymphatics after perinephritis or renal transplantation. In this case, histologic characteristics of the pseudocyst wall were suggestive of development from the parietal peritoneal layer encapsulating the kidney. This is the first case of retroperitoneal perirenal pseudocyst in a sheep.  相似文献   

TRANSCUTANEOUS ULTRASONOGRAPHY OF THE ABDOMEN IN THE NORMAL COMMON MARMOSET (CALLITHRIX JACCHUS)     

Wencke M. Wagner  Robert M. Kirberger 《Veterinary radiology & ultrasound》2005,46(3):251-258

Ultrasonographic examinations were performed on 17 clinically healthy adult common marmosets to gain information about the normal abdominal echoanatomy. The marmosets were 1.5-9 years of age and weighed between 328 and 506g. Marked species-specific differences compared with the cat or dog were noted. Good images of the kidneys, bladder, spleen, adrenal glands, liver, and the gastrointestinal tract could be obtained. The pancreas, caecum, and abdominal lymph nodes were not seen. The spleen was the least echogenic organ, followed by the medium echogenic liver and the sometimes isoechoic, but mostly hyperechoic renal cortex. The kidneys had a poor corticomedullary distinction. The prominent right lobes of the liver extended caudally far beyond the costal arch. The gallbladder had a bi- to multi-lobed appearance with a wide, tortuous cystic duct. The pylorus was centrally positioned. The adrenal glands were readily seen, but should not be confused with the adjacent spleen. A statistically significant (P<0.05) difference between female and male kidney, and right adrenal gland length was present.  相似文献   

Lactation curves in captive Iberian red deer (Cervus elaphus hispanicus)     

García A  Landete-Castillejos T  Molina A  Albiñana B  Fernández C  Garde J  Gallego L 《Journal of animal science》1999,77(12):3150-3155

This study examines milk production and the effect of milk production and sex of calf on body weights and gains of red deer calves and hinds of the Iberian subspecies (Cervus elaphus hispanicus). Milk production was assessed in 14 hinds by weighing calves before and after suckling and by adjusting these values to the Gamma function. Gamma estimates of total milk production up to d 105 were similar to the amounts computed directly from double weighing. Hinds showed two types of lactation curve: 1) the standard mammal lactation curve, with an asymmetrical peak at wk 2 to 4 (Type I) and 2) decreasing curves with no peak (Type II). Although there was great interindividual variability, hinds with Type I curves showed a trend to produce more milk than those with Type II. The type of curve did not seem to affect weight variables of the calf or those of the dam. Calves that gained more weight consumed greater amounts of milk (P<.05). Males were heavier than females at birth (P<.05), but males did not differ from females in their weight at 105 d, milk consumption, and gain. Gender did not affect hind weight, but dams of male calves showed a trend to be lighter (P = .063) at d 105 than dams of female calves. Our results suggest that suckling differences found in other studies between male and female calves may not involve differences in milk production, although other rearing costs seem to affect hind weight losses. They also suggest that the curve type may not depend only, as reported, on the nutrition plane.  相似文献