Carbon kinetics of milk formation in Holstein cows in late lactation   总被引：3，自引：0，他引：3  

T W Boutton  H F Tyrrell  B W Patterson  G A Varga  P D Klein 《Journal of animal science》1988,66(10):2636-2645

Carbon transfer to milk in Holstein cows in late lactation was measured by introducing changes in the natural stable carbon isotope composition of the feed. Six Holstein cows in mid-lactation were placed on a diet naturally low in 13C (-25.0% vs Pee Dee belemnite [PDB] an international carbon isotope standard), based on alfalfa-barley, and six others were placed on a diet naturally enriched in 13C (-11.5% vs PDB), based on corn. After a 7-wk equilibration period on these diets, three cows were switched from alfalfa-barley to corn, and three were switched from corn to alfalfa-barley. The three other cows in each group served as controls. 13C/12C ratios were measured in daily morning milk samples during the week before and for 6 wk after the changes in diet. After the diets had been switched, milk isotope ratios rapidly approached the isotopic composition of the new diet, indicating rapid transfer of dietary carbon into milk. The data were consistent with a model whereby milk was synthesized from a single precursor pool that responded rapidly to dietary perturbation. The milk precursor pool had a half-life of approximately .9 d and had a mass of approximately 7 kg of carbon, which was renewed daily by the entry of 5 kg of digestible dietary carbon.  相似文献   

Lead in seawater     

Patterson C 《Science (New York, N.Y.)》1974,183(4124):553-554

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Epidural injection of xylazine for perineal analgesia in horses   总被引：7，自引：0，他引：7  

P H LeBlanc  J P Caron  J S Patterson  M Brown  M A Matta 《Journal of the American Veterinary Medical Association》1988,193(11):1405-1408

Local anesthetics given in the epidural space of a horse may cause hind limb weakness in addition to analgesia. Because alpha 2 agonists given by epidural injection cause sensory blockade without motor effects in human beings and other species, their use in veterinary anesthesia is appealing. This study was designed to examine the effectiveness of xylazine HCl, an alpha 2 agonist commonly used in horses. Xylazine, 0.9% NaCl, and lidocaine were given by epidural injection to horses subjected to perineal electrical stimulation. Administration of xylazine (0.17 mg/kg of body weight, diluted to a 10-ml volume, using 0.9% NaCl) induced approximately 2.5 hours of local analgesia without apparent side effects. Higher doses of xylazine caused mild hind limb ataxia. Administration of lidocaine induced a similar duration of analgesia, with severe hind limb ataxia (100% incidence). We concluded that xylazine given by epidural injection results in safe, effective perineal analgesia in horses.  相似文献   

Mucopolysaccharidosis in a cat.     

K R Cowell  P F Jezyk  M E Haskins  D F Patterson 《Journal of the American Veterinary Medical Association》1976,169(3):334-339

A young adult female Siamese cat born of a mother-son mating was referred because of dwarfism, facial abnormalities, severe skeletal deformities, multifocal neurologic deficits, and retinal atrophy. Cats of similar appearance had been observed in a previous litter of the same parents. Metachromatic inclusion bodies were demonstrated in circulating leukocytes. The urine contained a high concentration of mucopolysaccharide, as detected by the toluidine blue spot test. The uronic acid content of the cetylpyridinium chloride-precipitable mucopolysaccharide in the urine was 17 times greater than that in the urine from a control cat of the same age and breed.  相似文献   

Plasma levels of muscle enzymes in the Pietrain pig in relation to the acute stress syndrome     

W M Allen  S Berrett  J D Harding  D S Patterson 《The Veterinary record》1970,87(14):410-411

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White-Crowned Sparrows (Zonotrichia leucophrys nuttalli) to Song     

Petrinovich L  Patterson T  Peeke HV 《Science (New York, N.Y.)》1976,191(4223):206-207

The pattern of responses of both male and female white-crowned sparrows to playback of recorded song depends on whether the female has eggs, nestlings, or fledglings, and on the behavior under consideration. These patterns can be understood in the context of the behavior patterns appropriate during each of the different stages of the reproductive cycle.  相似文献   

Comparative biological and biochemical studies in hybrid chicks     

D. S. P. Patterson  D. Sweasey  C. Nancy Hebert  R.B.A. Carnaghan 《British poultry science》1967,8(4):273-278

The normal course of development of electrophoretic serum protein patterns has been examined in two hybrid strains of chicks during the 7 weeks after hatching and was found to proceed distinctively. Hybrid A (susceptible to aflatoxin) had an almost constant mean serum protein concentration over this period. On the other hand, after a high mean concentration (4–09 g./100 ml.) in day‐old chicks of hybrid B (less susceptible to aflatoxin) there was a fall to 2.69 g./100 ml. at 7 days, followed by a gradual increase to 3.28 g./100 ml., approximately the level found throughout the experiment in hybrid A.

Proportions of albumin and total globulins varied in an almost identical manner in each group. Day‐old chicks of hybrid A had significantly lower β‐ and γ‐globulin concentrations and at 7 days, when there was a maximum difference in mean total protein concentrations, the serum albumin content was significantly higher in this hybrid.  相似文献   

Reproducibility of a commercial in vitro allergen-specific assay for immunoglobulin E in dogs     

Patterson AP  Schaeffer DJ  Campbell KL 《The Veterinary record》2005,157(3):81-85

Samples of serum taken from 42 dogs with clinical signs and histories indicating pruritic skin disease and/or diseases of the ear were tested in a commercial allergen-specific assay for immunoglobulin E. Dogs which had been treated with glucocorticoids and/or antihistamines were not excluded. The samples were separated into two equal aliquots, given different randomised numbers, and analysed in two batches on two separate days. The laboratory was blinded to the identification numbers and the history of each dog, but knew the purpose of the study. The results for 48 allergens were expressed in modified absorbance units (MAU). The overall median MAU was 29. For each allergen the mean difference between the MAU values of the paired duplicates was determined and the difference was compared to zero by a paired t test. The number of means that were not 0 (P<0.05) in each allergen group were: seven of 10 grasses, seven of nine weeds, two of 13 trees, six of 10 fungi, and three of six environmental allergens. A single 2 x 2 table for the 48 allergens was created with MAU > or = 60 defined as 'positive' and < 60 as 'negative'. There were 116 of 188 (62 per cent) pairs that were reproducibly 'positive' and 1756 of 1828 (96 per cent) pairs that were reproducibly 'negative'.  相似文献   

Closing the supply versus demand gap for veterinary pathologists: a multifaceted problem in need of a multifaceted solution     

Cockerell GL  Patterson DR 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(7):660-661

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Transmission of Phytophthora ramorum in Mixed-Evergreen Forest in California     

Davidson JM  Wickland AC  Patterson HA  Falk KR  Rizzo DM 《Phytopathology》2005,95(5):587-596

ABSTRACT During 2001 to 2003, the transmission biology of Phytophthora ramorum, the causal agent of sudden oak death, was studied in mixedevergreen forest, a common forest type in northern, coastal California. Investigation of the sources of spore production focused on coast live oak (Quercus agrifolia) and bay laurel (Umbellularia californica), dominant hosts that comprised 39.7 and 46.2% of the individuals at the study site, respectively. All tests for inoculum production from the surface of infected coast live oak bark or exudates from cankers were negative. In contrast, sporangia and chlamydospores were produced on the surface of infected bay laurel leaves. Mean number of zoospores produced from infected bay laurel leaves under natural field conditions during rainstorms was 1,173.0 +/- SE 301.48, and ranged as high as 5,200 spores/leaf. P. ramorum was recovered from rainwater, soil, litter, and streamwater during the mid- to late rainy season in all 3 years of the study. P. ramorum was not recovered from sporadic summer rains or soil and litter during the hot, dry summer months. Concentrations of inoculum in rainwater varied significantly from year to year and increased as the rainy season progressed for the two complete seasons that were studied. Potential dispersal distances were investigated for rainwater, soil, and streamwater. In rainwater, inoculum moved 5 and 10 m from the inoculum source. For soil, transmission of inoculum was demonstrated from infested soil to bay laurel green leaf litter, and from bay laurel green leaf litter to aerial leaves of bay laurel seedlings. One-third to one-half of the hikers tested at the study site during the rainy season also were carrying infested soil on their shoes. In streamwater, P. ramorum was recovered from an unforested site in pasture 1 km downstream of forest with inoculum sources. In total, these studies provide details on the production and spread of P. ramorum inoculum in mixed-evergreen forest to aid forecasting and managing disease transmission of this environmentally destructive pathogen.  相似文献