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991.
Knauer M Stalder KJ Karriker L Baas TJ Johnson C Serenius T Layman L McKean JD 《Preventive veterinary medicine》2007,82(3-4):198-212
Physical and reproductive conditions of cull sows (3158) from two U.S. Midwestern harvest plants were assessed. Body condition, feet, shoulders, teeth, lungs, and reproductive tracts were visually evaluated for gross lesions on harvested sows. PROC FREQ (SAS, Cary, NC) was used to calculate the frequency of each binary trait event. Pearson chi-square tests were used to test the alternative hypothesis that a linear association existed between binary traits and body condition score (BCS). The most common foot lesions observed were rear (n = 2064, 67.5%) and front (n = 1024, 32.9%) heel lesions. Cracked hooves were found on the front feet of 703 (22.6%) and rear feet of 552 (18.1%) sows. Rear digital overgrowth was observed in 644 (21.1%) sows. The most common reproductive gross lesion observed among harvested cull sows was acyclic ovaries (n = 277, 9.0%). Presence of acyclic ovaries increased (p < 0.01) as BCS decreased. Cystic ovaries were found in 192 (6.3%) sows, which increased (p < 0.01) as BCS increased. Pneumonia was observed in 298 (9.7%) sows, and increased in frequency as BCS decreased (p < 0.01). The most frequently observed shoulder lesion among harvested cull sows was shoulder abrasions (n = 394, 12.5%). The presence of shoulder abrasions increased (p < 0.01) as BCS decreased. The prevalence of reproductive lesions detected in the present study was less than the reported percentage of sows culled for reproductive failure from previous studies based on record keeping summaries. 相似文献
992.
Progeny of a diallel among Simmental, Limousin, Polled Hereford and Brahman breeds of cattle were evaluated over 5 yr for preweaning and postweaning growth, hip height and pelvic size. Calves from Brahman and Simmental dams had the highest preweaning gains and weaning weights, and those from Polled Hereford dams had the lowest (P less than .05). Differences in the availability of milk and postpartum compensatory gains in progeny of Brahman dams could have contributed to these results. However, calves from Simmental, Limousin and Polled Hereford dams had significantly greater feedlot daily gains than those from Brahman dams. Yearling hip height and pelvic area were lower for progeny of Polled Hereford dams, whereas calves from Simmental, Limousin and Brahman dams were not different for these traits. A series of linear comparisons among these four breeds using least-squares means to estimate general and specific combining ability and maternal effects found significant, negative maternal effects for Polled Hereford for preweaning gain and weaning weight. A positive maternal effect (P less than .05) for Limousin was found for feedlot gain. General combining ability and maternal estimates were significant and variable in most comparisons for yearling hip height and pelvic area. Heterosis estimates were positive and significant in all crosses with Brahman for preweaning gain, weaning weight, yearling weight, hip height and pelvic area. Significant, positive heterosis was also found in Polled Hereford crosses with Limousin and Simmental for preweaning gain, weaning weight and yearling weight. 相似文献
993.
994.
Kinne J Johnson B Jahans KL Smith NH Ul-Haq A Wernery U 《Tropical animal health and production》2006,38(3):207-213
An adult male dromedary bull was diagnosed with pulmonary tuberculosis (Tb). The dromedary was severely emaciated and died
2 months after the onset of the disease. It exhibited typical Tb lesions in both lungs and lung lymph nodes. A guinea pig
inoculated with lung tissue from the Tb camel died after 3 weeks from typical Tb. Mycobacteria were isolated from the dromedary's
lung and lung lymph nodes and also from different organs of the guinea pig. The microorganism was identified as member of
the antelope clade of the Mycobacterium tuberculosis complex. 相似文献
995.
Sabrina Reilly Reza Seddighi Christine M Egger Barton W Rohrbach Thomas J Doherty Wen Qu James R Johnson 《Veterinary anaesthesia and analgesia》2013,40(3):290-296
ObjectiveThe objectives of this study were to determine the effects of fentanyl on the end-tidal concentration of sevoflurane needed to prevent motor movement (MACNM) in response to noxious stimulation, and to evaluate if acute tolerance develops.Study designRandomized cross-over experimental study.AnimalsSix healthy, adult (2–3 years old), intact male, mixed-breed dogs weighing 16.2 ± 1.1 kg.MethodsSix dogs were randomly assigned to receive one of three separate treatments over a 3 week period. After baseline sevoflurane MACNM (MACNM-B) determination, fentanyl treatments (T) were administered as a loading dose (Ld) and constant rate infusion (CRI) as follows: T1-Ld of 7.5 μg kg?1 and CRI at 3 μg kg?1 hour?1; T2-Ld of 15 μg kg?1 and CRI at 6.0 μg kg ?1 hour?1; T3-Ld of 30 μg kg?1 and CRI at 12 μg kg?1 hour?1. The MACNM was defined as the minimum end-tidal sevoflurane concentration preventing motor movement. The first post-treatment MACNM (MACNM-I) determination was initiated 90 minutes after the start of the CRI, and a second MACNM (MACNM-II) determination was initiated 3 hours after MACNM-I was established.ResultsThe overall least square mean MACNM-B for all groups was 2.66%. All treatments decreased (p < 0.05) MACNM, and the decrease from baseline was 22%, 35% and 41% for T1, T2 and T3, respectively. Percentage change in T1 differed (p < 0.05) from T2 and T3; however, T2 did not differ from T3. MACNM-I was not significantly different from MACNM-II within treatments.Conclusions and clinical relevanceFentanyl doses in the range of 3–12 μg kg?1 hour?1 significantly decreased the sevoflurane MACNM. Clinically significant tolerance to fentanyl did not occur under the study conditions. 相似文献
996.
Johnson LR Clarke HE Bannasch MJ De Cock HE 《Journal of the American Veterinary Medical Association》2004,225(3):395-400
OBJECTIVE: To investigate the correlation of cumulative rhinoscopic findings of hyperemia, mucus accumulation, and turbinate destruction with the type and severity of inflammatory infiltrates in nasal biopsy specimens of cats with or without upper respiratory tract disease. DESIGN: Prospective study. ANIMALS: Cats with (n = 11) and without (6) upper respiratory tract disease and cats with unknown medical histories (27). PROCEDURES; Lesions of hyperemia, mucus accumulation, and turbinate destruction detected rhinoscopically were each scored (scale, 0 [absent] to 3 [severe]), and a cumulative rhinoscopic score for each nasal cavity was calculated. Fifty biopsy specimens were examined histologically, and inflammatory infiltrates (lymphoplasmacytic or neutrophilic) were graded as absent, mild, moderate, or severe. Cumulative rhinoscopic scores and inflammation grades were compared for each specimen-cavity combination. RESULTS: In cats of known disease status, there was a positive but weak correlation between cumulative rhinoscopic scores and inflammation grades in biopsy specimens. In cats of unknown disease status, there was no similar correlation. Biopsy specimens with minimal inflammation were commonly obtained from nasal cavities with low rhinoscopic scores; specimens with moderate or severe inflammatory changes were frequently obtained from cavities that appeared normal rhinoscopically. Type of inflammatory infiltrates was not correlated with rhinoscopic signs of inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: The correlation of rhinoscopic findings with inflammation severity in nasal biopsy specimens (determined histologically) was weak or lacking in cats of known and unknown disease status, respectively. Results indicated that rhinoscopy with biopsy provides more complete evaluation of nasal disease than rhinoscopy alone in cats. 相似文献
997.
Keegan KG Arafat S Skubic M Wilson DA Kramer J Messer NM Johnson PJ O'Brien DP Johnson G 《Equine veterinary journal》2004,36(8):712-717
REASONS FOR PERFORMING STUDY: Subjective neurological evaluation in horses is prone to bias. An objective method of spinal ataxia detection is not subject to these limitations and could be of use in equine practice and research. HYPOTHESIS: Kinematic data in the walking horse can differentiate normal and spinal ataxic horses. METHODS: Twelve normal and 12 spinal ataxic horses were evaluated by kinematic analysis walking on a treadmill. Each body position signal was reduced to a scalar measure of uncertainty then fuzzy clustered into normal or ataxic groups. Correct classification percentage (CCP) was then calculated using membership values of each horse in the 2 groups. Subsequently, a guided search for measure combinations with high CCP was performed. RESULTS: Eight measures of body position resulted in CCP > or = 70%. Several combinations of 4-5 measures resulted in 100% CCP. All combinations with 100% CCP could be obtained with one body marker on the back measuring vertical and horizontal movement and one body marker each on the right fore- and hindlimb measuring vertical movement. CONCLUSIONS AND POTENTIAL RELEVANCE: Kinematic gait analysis using simple body marker combinations can be used objectively to detect spinal ataxia in horses. 相似文献
998.
Sandeep Raj Karna Paul Chambers Craig B. Johnson Preet Singh Lauren A. Stewart Nicolas Lopez-Villalobos Kavitha Kongara 《Journal of veterinary pharmacology and therapeutics》2020,43(6):538-546
This study was conducted to compare the efficacy of combinations of morphine, dexmedetomidine and maropitant in preventing the changes in electroencephalographic (EEG) indices of nociception in anaesthetized dogs subjected to a noxious electrical stimulus. In a crossover study, eight healthy adult dogs were randomly allocated to four groups: Mor: morphine 0.6 mg/kg; Dex + Mor: morphine 0.3 mg/kg + dexmedetomidine 5 μg/kg; Maro + Mor: morphine 0.3 mg/kg + maropitant 1 mg/kg; and Dex + Maro + Mor: morphine 0.2 mg/kg + dexmedetomidine 3 μg/kg + maropitant 0.7 mg/kg. Following intramuscular administration of test drugs in a minimal anaesthesia model, a supramaximal electrical stimulus (50 V at 50 Hz for 2 s) was applied and the EEG data were recorded. There were significant increases (p < .05) in the poststimulus median frequency (F50) only in groups Mor and Maro + Mor. Dex + Mor group had a significantly lower change in F50 and F95 compared to all other treatment groups. There was no correlation of the changes in EEG frequencies with blood plasma concentration of the drugs during and after noxious stimulation. Combination of dexmedetomidine and morphine was most effective in abolishing the changes in EEG indices in response to a noxious stimulus indicating a supra-additive interaction between these two drugs. 相似文献
999.
B.N. Kunkle J.C. Williams E.G. Johnson B.E. Stromberg T.A. Yazwinski L.L. Smith S. Yoon L.G. Cramer 《Veterinary parasitology》2013
Seven studies were conducted in commercial grazing operations to confirm anthelmintic efficacy, assess acceptability, and measure the productivity response of cattle to treatment with eprinomectin in an extended-release injectable formulation (ERI) when exposed to nematode infected pastures for 120 days. The studies were conducted under one protocol in the USA in seven locations (Arkansas, Idaho, Louisiana, Minnesota, Missouri, Oregon, and Wisconsin). Each study had 67–68 naturally infected animals for a total of 475 (226 female, 249 male castrate) Angus or beef-cross cattle. The animals weighed 133–335 kg prior to treatment and were approximately 3–12 months of age. The studies were conducted under a randomized block design based on pre-treatment body weights to sequentially form 17 replicates of four animals each within sex in each study. Animals within a replicate were randomly assigned to treatments, one to Eprinomectin ERI vehicle (control) and three to Eprinomectin ERI (5%, w/v eprinomectin). Treatments were administered at 1 mL/50 kg body weight once subcutaneously anterior to the shoulder. All animals in each study grazed one pasture throughout the observation period of 120 days. Cattle were weighed and fecal samples collected pre-treatment and on 28, 56, 84, and 120 days after treatment for fecal egg and lungworm larval counts. Positive fecal samples generally were cultured en masse to determine the nematode genera attributable to the gastrointestinal helminth infection. Bunostomum, Cooperia, Haemonchus, Nematodirus, Oesophagostomum, Ostertagia, and Trichostrongylus, when present, were referred to as strongylids. At all post-treatment sampling intervals, Eprinomectin ERI-treated cattle had significantly (P < 0.05) lower strongylid egg counts than vehicle-treated controls, with ≥95% reduction after 120 days of grazing. Over this same period, Eprinomectin ERI-treated cattle gained more weight (43.9 lb/head) than vehicle-treated controls in all studies. This weight gain advantage was significant (P < 0.05) in six of the studies with the Eprinomectin ERI-treated cattle gaining an average of 42.8% and the control cattle gaining 33.1% of their initial weight. No adverse reactions were observed in the treated animals. 相似文献
1000.
J W Tyler J Lakritz D Weaver G Johnson D VanMetre K Smith W Taylor A Jenny 《Journal of veterinary diagnostic investigation》2001,13(6):537-539
This study determined whether the immunoassay for cerebrospinal fluid 14-3-3 protein concentration was sensitive and specific in the diagnosis of naturally occurring clinical scrapie in sheep. Cerebrospinal fluid was collected from 9 sheep with the confirmed diagnosis of scrapie. Additionally, cerebrospinal fluid was collected from 13 clinically normal sheep, which originated from a closely monitored flock with no history of scrapie. Sensitivity and specificity were calculated using standard epidemiological methods. Cerebrospinal fluid immunoassay results did not differ significantly between positive and negative sheep. Test sensitivity varied from 0.55 to 0.66, depending on the choice of test endpoint. Test specificity varied from 0.30 to 0.77, depending on the choice of test endpoint. The 14-3-3 cerebrospinal fluid immunoassay appears to have no value in the diagnosis of clinical scrapie in sheep. 相似文献