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121.
R C Cutlip H D Lehmkuhl J M Sacks A L Weaver 《Journal of the American Veterinary Medical Association》1992,200(6):802-805
Goats from 28 states were tested for antibodies to caprine arthritis-encephalitis virus. Of 3,790 goats, 1,175 (31%) tested positive, and of 196 herds tested, 143 (73%) had 1 or more seropositive members. This prevalence, based on serum samples from all goats in the participating herds, was lower than most rates reported in other studies. Such studies were based on fewer samples, incomplete sampling of herds, or smaller geographic base. Prevalence was highest in western Pacific and northern plains regions, increased with age to 3 years, was highest among goats on family-owned farms, and was lowest in the Angora breed. Differences in prevalence was not related to gender or size of herd. 相似文献
122.
The relationship between colloid osmotic pressure (COP) and protein concentration was investigated for purified proteins and plasma samples obtained from cattle, horses, dogs, and cats. At equivalent concentrations, bovine albumin exerted a COP that exceeded that of gamma-globulins by a mean factor of 4.4. Similar relationships between COP and protein were observed in the other species. Consequently, for a given total protein concentration, COP was dependent on the albumin/gamma-globulins ratio. A commonly used nomogram for estimating COP from protein concentration, the Landis-Pappenheimer equation, did not provide reliable results for plasma samples from these species. 相似文献
123.
P L Ferrante J H Menninger P A Spencer D S Kronfeld 《American journal of veterinary research》1992,53(3):321-325
Four mares fed a low fiber, high soluble carbohydrate diet were used in a crossover design to evaluate the effects of dietary sodium bicarbonate (NaHCO3) supplementation during daily low-intensity submaximal working conditions. Mares were fed the diet at 1.7 times the maintenance energy requirement for mature horses at work. The horses tolerated the diet well and had no clinical abnormalities. Resting venous blood bicarbonate (HCO3), standard HCO3, and base excess (BE) concentrations significantly (P less than 0.05) increased with NaHCO3 supplementation, but no significant changes in resting venous blood pH or carbon dioxide tension (PCO2) were recorded. Venous blood HCO3, standard HCO3, BE, hemoglobin, and heart rate were significantly (P less than 0.05) increased and plasma lactate concentration was significantly (P less than 0.05) decreased in the control horses and in the horses given the NaHCO3 supplement during low-intensity submaximal exercise. There were no significant changes in venous blood pH, PCO2, or plasma protein concentration with exercise. Venous blood HCO3, standard HCO3, and BE concentrations were significantly (P less than 0.05) greater during submaximal exercise in horses given the NaHCO3 supplement. There were no significant differences in plasma lactate or total protein concentrations, blood pH, PCO2, or hemoglobin concentration between the 2 groups during exercise. 相似文献
124.
P O Ahmed M F Miller S D Shackelford L P Johnson S E Williams M A McCann J O Reagan 《Journal of animal science》1992,70(2):439-443
Thirty-two crossbred cattle (steers = 17; heifers = 15) exhibiting an ultrasound fat thickness at the 12 to 13th rib region of at least 10 mm were selected from a slaughter shift at a commercial packing plant. After splitting, alternating sides of each carcass were trimmed of 1) subcutaneous fat in excess of 6.4 mm; 2) all kidney, pelvic, and heart fat; and 3) all cod or udder fat and fat in the flank region. Both sides of each carcass were fabricated into subprimals (final trim level of 6.4 mm) according to normal industry procedures. Effect of hot-fat trimming, yield grade (3, 4, and 5), and gender on hot-fat trim, fabrication fat trim, major subprimal, and total subprimal yield of untrimmed and trimmed carcasses were determined. Higher numerical yield grade (YG) corresponded with higher (P less than .05) percentages of hot-fat trim. Hot-fat trimming increased (P less than .05) the difference in fabrication fat trim between steers and heifers and between YG 3 and YG 5. Steers and heifers differed (P less than .05) in percentage of major subprimals and total subprimals when processed conventionally, whereas hot-fat trimming eliminated this difference (P less than .05). Untrimmed YG 3 carcasses had 3.1 and 5.0% higher major subprimal yield (P less than .05) than untrimmed YG 4 and YG 5 carcasses, respectively, whereas hot-fat trimming reduced this difference to 2.5% for YG 4 and to 3.7% for YG 5.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
125.
L A Hopen P T Colahan T A Turner A J Nixon 《Journal of the American Veterinary Medical Association》1992,200(4):527-530
Subchondral cyst-like lesions of the cubital joint were diagnosed in 7 horses at the teaching hospital between 1983 and 1987. Diagnosis of the lesions was made by administration of intra-articular local anesthesia and/or radiographically. Initial treatment for all horses consisted of stall rest for 60 to 90 days. In addition, 2 horses were administered sodium hyaluronate intra-articularly, 1 horse was given injections of polysulfated glycosaminoglycans IM, and 1 horse was given phenylbutazone orally. Follow-up information was compiled 6 weeks to 4 years after initial examination. At the time of follow-up inquiry, 6 horses were sound for intended use and only 1 horse became lame when exercised. A logical approach to choice of surgical or nonsurgical treatment is proposed on the basis of these findings and those reported in the literature. 相似文献
126.
An Amaranthus rudis Saner (common water-hemp) biotype from a field treated for two consecutive years with a mixture of chlorimuron and metribuzin was tested in greenhouse and laboratory studies to assess resistance and cross-resistance to four acetolactale synthase (ALS)-inhibiting herbicides. The biotype demonstrated >1920-fold resistance at the whole plant level, and >850-fold resistance at the ALS enzyme to chlorimuron, compared with a susceptible biotype. This chlorimuron-resistant biotype was also cross-resistant to primisuifu-ron, haiosulfuron and imazethapyr. In greenhouse studies, atrazine alone or in combination with ALS-inhibiting herbicides provided excellent control of the resistant biotype of A. rudis . Combinations of dicamba and ALS-inhibitors also provided adequate control. Additionally, premixtures of flumetsulam and metolachlor and of dicamba and atrazine furnished excellent control of this chlorimuron-resistant A. rudis biotype. 相似文献
127.
Summary Serum and liver concentrations of selected macro-and trace minerals were determined in Senepol cattle at 8 sites (4 each in
a high and low rainfall region) during the dry and wet season on St Croix. At each site an average of 15 mature, lactating
cows, grazing native grass/legume pastures without supplementation were blood sampled each season. Liver samples were collected
(n=51) at slaughter from mature animals originating from the same sites. A preliminary analysis indicated no differences in
serum mineral concentrations between mature lactating cows and growing heifers. There were differences between sites for serum
magnesium (Mg) (P<0·001), copper (Cu) (P<0·05) selenium (Se) (P<0·001) and zinc (Zn) (P<0·01) in the dry season, and for Cu
(P<0·01), iron (Fe) (P<0·001) and Zn (P<0·01) in the wet season. Higher (P<0·001) serum concentrations of Mg, Cu, Fe and Zn
were observed in the dry season, while Se was higher (P<0·001) in the wet season. Liver concentrations of Cu and Fe were lower
(P<0·01) and liver molybdenum (Mo) (P<0·001) and Se (P<0·05) higher during the dry season. The seasonal differences in serum
Cu, Se and Zn concentrations have not been observed in other studies in the Central American region. More than 50% of serum
samples were deficient in phosphorus (P) regardless of season, and in Cu and Zn during the wet season. Mineral supplementation
should be considered.
Resumen Se determinó la concentración de minerales (macro y trazas) seleccionados, en ganado Senepol en ocho sitios: cuatro de ellos en una región de alta precipitación y los otros cuatro en regiones de baja precipitación pluvial, durante la estación seca y lluviosa en la isla de Sta Cruz. En cada sitio, un promedio de 15 vacas lactantes, pastoreando pasto nativo y pasturas con leguminosas sin suplementación, se sangraron en cada estación. Se colectó tejido hepático (n=51) en el matadero local, de animales maduros provenientes de los sitios estudiados. Un análisis preliminar, no indicó diferencias en concentraciones séricas de minerales entre animales maduros lactandos y novillas en crecimiento. Hubo diferencias en cuanto a localización respecto al magnesio sérico (Mg) (P<0·001), cobre (Cu) (P<0·05) selenio (Se) (P<0·001) y zinc (Zn) (P<0·01) en la estación seca y para Cu (P<0·01), hierro (Fe) (P<0·001) y Zn (P<0·01) en la estación lluviosa. Se observaron concentracionas séricas màs altas (P<0·001) de Mg, Cu, Fe y Zn en la estación seca, mientras que el Se fue más alto (P<0·001) en la estación lluviosa. Las concentraciones hepáticas de Cu y Fe fueron bajas (P<0·01) y las de molibdeno hepático (Mo) (P<0·001) y Se (P<0·05), fueron altas durante la estación seca. Las diferencias estacionales en concentraciones de Cu, Se, y Zn sérico, no habian sido observadas en otros estudios en la región centroamericana. Mas de 50 por ciento de las muestras de suero fueron deficientes en fósforo (P) sin tener en cuenta la estación y en Cu y Zn durante la estación lluviosa. Se sugiere la necesidas de suplementación mineral.
Résumé Les auteurs ont déterminé les concentrations sériques et hépatiques d'un certain nombre d'oligo éléments et de sels minéraux sur des bovins Senepol éléves sur 8 sites (quatre pour chaque région à forte et faible pluviométrie) pendant la saison humide et la saison sèche sur l'lle Sainte Croix. Sur chaque site, des prélèvements de sang ont été effectués pendant chaque saison sur la base d'une moyenne de 15 vaches adultes en lactation, paturant sur des parcours naturels de graminées/légumineuses, sans complémentation. Les prélèvements de foie (n=51) ont été collectés à l'abattoir sur des animaux adultes originaires de ces mêmes endroits. Une analyse préliminaire n'a indiqué aucune différence dans les concentrations minérales du sérum entre les vaches adultes en lactation et les génisses en cours de croissance. Il y avait des différences entre les sites pour le magnésium sérique (Mg) (P<0,001), le cuivre (Cu) (P<0,05), le sélénium (Se) (P<0,001) et le zinc (Zn) (P<0,01) en saison sèche et pour le cuivre (Cu) (P<0,01), le fer (Fe) (P<0,001) et le zinc (Zn) (P<0,01) en saison humide. En saison sèche, des concentrations plus élevées (P<0,001) on été observées pour Mg, Cu, Fe et Zn alors que le sélénium (Se) était plus abondant en saison humide. Les concentrations hépatiques en Cu et Fe étaient plus basses (P<0,01) mais celles en Molybdène (Mo) (P<0,001) et en sélénium (P<0,05) plus élevées au cours de la saison sèche. Les différences saisonnières entre les concentrations sériques de Cu, Se et Zn n'ont pas été observées en Amérique centrale par d'autres auteurs. Plus de 50 p. 100 des échantillons de sérum étaient carencés en phosphore (P) quelle que soit la saison, et en Cu et Zn pendant la saison humide. Il conviendrait de prendre en considération la complémentation minérale.相似文献
128.
STEPHEN D. GILSON DVM DONALD L. PIERMATTEI DVM PhD DiplomateACVS PETER D. SCHWARZ DVM DiplomateACVS 《Veterinary surgery : VS》1989,18(2):114-122
Humeroulnar subluxation was treated surgically in 13 dogs with 18 affected elbows using a proximal osteotomy of the ulna that allowed the ulna to elongate dynamically. Distal humeroulnar subluxation was secondary to premature closure of the distal ulnar physis in 16 elbows. One distal subluxation was secondary to a radioulnar synostosis, and one proximal subluxation developed after premature closure of the distal radial physis. The mean follow-up time was 22 months. Twenty-eight percent of the elbows were judged to have excellent results, 22% good results, 50% fair results, and none was judged to have a poor outcome. The presenting lameness grade and the severity of preoperative and postoperative humeroulnar subluxation had significant correlations with the prognosis. Associated orthopedic abnormalities and complications of concurrent surgical procedures affected the outcome in several dogs. Overall, the dynamic proximal ulnar osteotomy was a simple and effective technique for the treatment of uncomplicated humeroulnar subluxation. 相似文献
129.
Water-stable macro-aggregate size fractions (>2.0 mm, 1.0–2.0 mm, 0.5–1.0 mm and 0.25–0.5 mm) and non-aggregated soil from a sandy loam under long-term clover-based pasture and from grass pasture were analysed to determine the role of acid- and water-extractable carbohydrate C, total hyphal length, microbial biomass, organic C and total and mycorrhizal root length in stabilization of the aggregates. Aggregates were examined by scanning electron microscopy (SEM) and the particle-size distribution of the size fractions was also determined. Macro-aggregation increased under grass, relative to clover-based pasture; however, the properties of the aggregate fractions measured did not reflect this difference. Microbial-biomass C, extractable-carbohydrate C, hyphal length, total and mycorrhizal root length and organic C content of the soils were poorly correlated with macro-aggregation. Within the aggregates, the proportion of 250–1000-km sand was smaller and clay, silt and fine sand (20–250 μm) were greater relative to non-aggregated soil, suggesting that the >250-μm sand in the non-aggregated soil limited the stabilization of macro-aggregates. Under SEM, no enmeshment of aggregates by hyphae and roots was apparent. Although 50–160 m hyphae g?1 soil was found within the aggregates, calculations showed that on average only 5 to 13 lengths of hyphae were associated with each 250-μm cube of soil within the aggregates, and suggested little potential to stabilize the aggregates by enmeshing. On average, all >2.0-mm aggregates contained less than 3.6 mm of roots and less than 50% by weight of <2.0-mm aggregates contained a single length of root. The findings cast doubt about the role of hyphae and fine roots in the stabilization of macro-aggregates through an enmeshing mechanism in sandy soils. 相似文献
130.
Eleven hybridoma cell lines producing monoclonal antibodies (MAbs) against intact budgerigar fledgling disease (BFD) virions were produced and characterized. These antibodies were selected for their ability to react with BFD virions in an enzyme-linked immunosorbent assay. Each of these antibodies was reactive in the immunofluorescent detection of BFD virus-infected cells. These antibodies immunoprecipitated intact virions and specifically recognized the major capsid protein, VP1, of the dissociated virion. The MAbs were found to preferentially recognize native BFD virus capsid protein when compared with denatured virus protein. These MAbs were capable of detecting BFD virus protein in chicken embryonated cell-culture lysates by dot-blot analysis. 相似文献