Discrimination between individual humans by domestic fowl (Gallus gallus domesticus).     

H Davis  A Taylor 《British poultry science》2001,42(2):276-279

1. We demonstrate that Barred-Rock and Isa-Brown hens can discriminate between the presence of 2 different humans and use this information as a cue for whether or not to make an operant response. 2. This demonstration in domestic fowl, the first of its kind in any avian subject, is consistent with a growing body of evidence that many species, including agricultural animals, are surprisingly adept at differentiating between humans. 3. Such a discriminative ability carries considerable implications for issues related to husbandry, production and welfare.  相似文献   

MAGNETIC RESONANCE IMAGING OF THE EQUINE STIFLE     

Susan J.  Holcombe  VMD  MS  Alicia L.  Bertone  DVM  PhD  David S.  Biller  DVM  Valerie  Haider  DVM 《Veterinary radiology & ultrasound》1995,36(2):119-125

The purpose of this study was to define normal gross anatomic structures in the equine stifle with magnetic resonance images. Magnetic resonance (MR) images were made in sagittal, 15° supinated, transverse, and dorsal planes of two equine stifles. The MR images were scrutinized by comparing MR images to dissection specimens and frozen cross sections of stifle joints. Sagittal and 15° supinated images were the most valuable in assessing articular cartilage, subchondral bone, and soft tissue structures within the joint. Cranial and caudal cruciate ligaments, medial and lateral menisci, meniscotibial and meniscofemoral ligaments, long digital extensor tendon, and patellar ligaments were easily evaluated. MR images provided substantially more gross anatomical information than the currently available imaging modalities.  相似文献   

Divergent selection for postweaning feed conversion in Angus beef cattle: II. Genetic and phenotypic correlations and realized heritability estimate.     

M D Bishop  M E Davis  W R Harvey  G R Wilson  B D VanStavern 《Journal of animal science》1991,69(11):4360-4367

A single generation divergent selection study, replicated four times (1983, 1984, 1985, and 1986), was conducted to assess genetic differences between progeny of high and low feed conversion sires in Angus beef cattle and to determine correlated response for weight gain (ADG140), feed intake (AVFD140), and BW (OFFTSTWT) in a time- (140-d) and fat-constant (8.9 mm) period. Realized heritability estimates for unadjusted (feed/gain; FEFF140; .26) and adjusted feed conversion (adjusted as recommended by the BIF, 1986; ADJFDEFF; .46) were obtained. The difference in heritability estimates reflects variation accounted for by adjustment for BW differences, and thus maintenance requirements, of individual progeny. Phenotypic and "pseudo" realized genetic correlations of FEFF140 with ADG140, AVFD 140, and OFFTSTWT were -.33 and -.66, .49 and -.26, and .15 and -.41, respectively. Phenotypic and "pseudo" realized genetic correlations of ADJFDEFF with ADG140, AVFD140, OFFTSTWT, and FEFF140 were -.54 and -.59, .30 and -.23, .27 and -.36, and .97 and .49, respectively. Subcutaneous fat (as estimated by ultrasonic measurement; BF140) had phenotypic and "pseudo" realized genetic correlations with FEFF140 of -.33 and .66, respectively, and with ADJFDEFF of -.44 and -.58, respectively.  相似文献   

Open Intestinal Anastomosis with Surgical Stapling Equipment in 24 Dogs and Cats     

SHARON L. ULLMAN DVM  MS    MICHAEL M. PAVLETIC DVM  Dipiomate ACVS  GEOFFREY N. CLARK DVM 《Veterinary surgery : VS》1991,20(6):385-391

Surgical stapling equipment was used to perform open antiperistaltic side-to-side ("functional end-to-end") entero-anastomoses in 20 dogs and 4 cats. Twenty-one anastomoses healed uneventfully. Seven animals with severe bacterial peritonitis required open peritoneal drainage and delayed abdominal closure. There was postoperative leakage at the anastomotic site in two dogs and a localized abscess at the staple line in one cat. No long-term complications occurred in follow-up periods of 3 to 29 months.  相似文献   

Human rights and credibility     

Davis C 《Science (New York, N.Y.)》1986,231(4741):908

  相似文献   

A defect in thyroglobulin synthesis in an inherited ovine goitre: possible neonatal respiratory distress syndrome     

Jones BR  Greenway RM  Jolly RD  Labuc RH  Davis GB 《New Zealand veterinary journal》1986,34(9):145-148

A ram lamb with congenital goitre showed signs of respiratory distress at birth. All previously affected lambs from this flock bad been born dead or bad died soon after birth. The serum free-thyroxine level at 1 birth was low (9.8 pmol/l) but treatment with oral L-thyroxine resulted in an increase in thyroxine blood levels to above normal and regression of the goitre. Four weeks after withdrawal of thyroid supplementation and when the lamb was eight weeks old, the radio iodide uptake mechanism of the thyroid glands was shown to be intact but the iodide was not organified. Low normal peroxidase activity was demonstrated in fresh thyroid tissue but gel electrophoresis demonstrated an absence of normal thyroglobulin from extracts of the goitrous thyroid. This lamb and the other affected lambs of this flock have an inherited defect in thyroglobulin synthesis and it is likely that the respiratory distress was associated with the low levels of thyroid hormone affecting foetal lung development.  相似文献   

Pathogenicity of Fusarium oxysporum f. sp. Cepae and its interaction with Pyrenochaeta terrestris on onion   总被引：1，自引：0，他引：1  

August E. Kehr  Muriel J. O'Brien  Elmo W. Davis 《Euphytica》1962,11(2):197-208

Onion breeding lines known to be resistant to Pyrenochaeta terrestris showed, in several locations, root-pruning symptoms that have been usually associated with only the action of P. terrestris. Fusarium oxysporum f. sp. cepae was invariably isolated from affected roots and the stem-plate area of these pink-root-resistant lines. Symptoms not commonly associated with the action of Fusarium, including darkening of dry scales of yellow bulbs and a reddening of scales of white bulbs, were noted. Controlled tests were conducted to establish (a) the pathogenicity of four isolates of F. oxysporum f. sp. cepae, (b) the reaction of onion breeding lines to inoculation at various temperatures with both the pink root and the Fusarium bulb rot organism, and (c) the pathogenic interaction of F. oxysporum f. sp. cepae with P. terrestris. The Fusarium isolates were pathogenic over a wide range of temperatures (20 to 38°C.). Host reaction to the organisms in combination depended on the level of susceptibility that was the greater to one or the other organism. Resistance to one did not markedly modify susceptibility to the other when both were present. Resistance to F. oxysporum f. sp. cepae was found in several onion lines.Horticulturist, Pathologist, and Horticulturist, respectively, United States Department of Agriculture, Beltsville, Maryland, U.S.A.  相似文献   

Government and quality in science     

Davis BD 《Science (New York, N.Y.)》1989,246(4931):736

  相似文献   

Changes in liveweight and behaviour of alpaca dams and offspring following weaning     

Pollard JC  Littlejohn RP  Davis GH 《New Zealand veterinary journal》1993,41(4):161-165

The effects of offspring sex, weight, age, and level of interaction with the dam on responses to weaning were examined to assist in the development of a weaning protocol for alpacas. In the first study, preand post-weaning activities, and weight change over Days -12-0,0-7 and 7-16 with respect to weaning, were recorded for 20 dam-offspring (hembra-cria) pairs aged 81-200 days. Pre-weaning changes in dam and offspring weights were positively related (P<0.05). Although heavier crias tended to be found closer to their dams than lighter crias (P<0.05) no additional effect of age on the dam-offspring relationship was found. Following weaning, cria growth rates were low over Days 0-7 but improved over Days 7-16, and hembra weight change followed the same pattern. Over Days 0-2, grazing and sitting activities of hembras and crias were replaced by standing and walking along paddock fencelines, although by Day 2 fenceline activities had decreased (P<0.05). Crias which were more frequently observed at fencelines had lower post-weaning growth rates (P<0.05). In the second study, pre-weaning sucking behaviour, and weight change over Days -30-0, 0-8 and 8-16 with respect to weaning, were recorded for 19 hembra-cria pairs aged 124-160 days. During 10 hours of observation on Days -5 and -4, the total duration of sucking by individual crias varied from 0-18 minutes, and the mean +/- SEM duration of sucking was 1.94 +/- 0.113 minutes. Cria sucking behaviour was positively related to growth rate prior to and weight at weaning (P<0.05). As in the first study, pre-weaning changes in dam and offspring weights were positively related (P<0.05). Following weaning, growth rates of the crias were depressed and the hembras lost weight over Days 0-8 and 8-16. The changes in growth rate and behaviour in Studies 1 and 2 indicated that weaning can be stressful for hembras and crias. However, there was no evidence from either study that pre-weaning behavioural or physical characteristics were related to the changes.  相似文献   

Self-Assembled Metal Colloid Monolayers: An Approach to SERS Substrates     

Freeman RG  Grabar KC  Allison KJ  Bright RM  Davis JA  Guthrie AP  Hommer MB  Jackson MA  Smith PC  Walter DG  Natan MJ 《Science (New York, N.Y.)》1995,267(5204):1629-1632

The self-assembly of monodisperse gold and silver colloid particles into monolayers on polymer-coated substrates yields macroscopic surfaces that are highly active for surface-enhanced Raman scattering (SERS). Particles are bound to the substrate through multiple bonds between the colloidal metal and functional groups on the polymer such as cyanide (CN), amine (NH(2)), and thiol (SH). Surface evolution, which can be followed in real time by ultraviolet-visible spectroscopy and SERS, can be controlled to yield high reproducibility on both the nanometer and the centimeter scales. On conducting substrates, colloid monolayers are electrochemically addressable and behave like a collection of closely spaced microelectrodes. These favorable properties and the ease of monolayer construction suggest a widespread use for metal colloid-based substrates.  相似文献