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261.
Evaluation of a Computer‐aided Lung Auscultation System for Diagnosis of Bovine Respiratory Disease in Feedlot Cattle 下载免费PDF全文
A.V. Mang S. Buczinski C.W. Booker E. Timsit 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(4):1112-1116
Background
A computer‐aided lung auscultation (CALA) system was recently developed to diagnose bovine respiratory disease (BRD) in feedlot cattle.Objectives
To determine, in a case–control study, the level of agreement between CALA and veterinary lung auscultation and to evaluate the sensitivity (Se) and specificity (Sp) of CALA to diagnose BRD in feedlot cattle.Animals
A total of 561 Angus cross‐steers (initial body weight = 246 ± 45 kg) were observed during the first 50 day after entry to a feedlot.Methods
Case–control study. Steers with visual signs of BRD identified by pen checkers were examined by a veterinarian, including lung auscultation using a conventional stethoscope and CALA that produced a lung score from 1 (normal) to 5 (chronic). For each steer examined for BRD, 1 apparently healthy steer was selected as control and similarly examined. Agreement between CALA and veterinary auscultation was assessed by kappa statistic. CALA''s Se and Sp were estimated using Bayesian latent class analysis.Results
Of the 561 steers, 35 were identified with visual signs of BRD and 35 were selected as controls. Comparison of veterinary auscultation and CALA (using a CALA score ≥2 as a cut off) revealed a substantial agreement (kappa = 0.77). Using latent class analysis, CALA had a relatively high Se (92.9%; 95% credible interval [CI] = 0.71–0.99) and Sp (89.6%; 95% CI = 0.64–0.99) for diagnosing BRD compared with pen checking.Conclusions
CALA had good diagnostic accuracy (albeit with a relatively wide CI). Its use in feedlots could increase the proportion of cattle accurately diagnosed with BRD. 相似文献262.
Two Methods of Vitrification Followed by In Vitro Culture of the Ovine Ovary: Evaluation of the Follicular Development and Ovarian Extracellular Matrix 下载免费PDF全文
FT Bandeira AA Carvalho SV Castro LF Lima DA Viana JSAM Evangelista MJS Pereira CC Campello JR Figueiredo APR Rodrigues 《Reproduction in domestic animals》2015,50(2):177-185
The aim of this study was to evaluate the influence of two vitrification techniques on the extra cellular matrix (ECM) and ovarian follicular development. The ovarian cortex was fragmented (9 mm3) and divided into six groups, viz. fresh control, cultured control, vitrified by the Ovarian Tissue Cryosystem (OTC) method, conventional solid surface vitrification (SSV) method, OTC/cultured and SSV/cultured. Follicles from all the fragments were analysed for morphology, development and viability. The ECM was evaluated based on the condition of collagen and reticular fibres and the immunolocalization of type I collagen and fibronectin. After 7 days of culture, the tissue vitrified by OTC revealed a higher percentage (p < 0.05) of morphologically normal (30.66%) and viable (60.00%) follicles when compared with those vitrified using the SSV technique (21.33% and 23.00%). In all the fragments cultured, regardless of the vitrification method, a significantly higher percentage of developing follicles was observed when compared with the non‐cultured tissue. Analysis of the type I collagen showed increased immunostaining after the in vitro culture in the vitrified fragments. In conclusion, the OTC is better for preserving the follicular viability and morphology and maintaining the integrity of the extracellular matrix components of the ovine ovary. 相似文献
263.
D.S. BUARQUE P.F. CASTRO F.M.S. SANTOS I.P.G. AMARAL S.M. OLIVEIRA K.B. ALVES L.B. CARVALHO JR R.S. BEZERRA 《Aquaculture Nutrition》2010,16(4):359-369
The aim of this study was to examine proteinases and peptidases from the hepatopancreas of two sub‐adult stages of Farfantepenaeus subtilis: SAS6 (5.93 ± 0.69 g wet weight) and SAS13 (13.26 ± 0.60 g wet weight). Trypsin and chymotrypsin activity was higher in the extract from the SAS6 individuals (P < 0.05). The highest activity among aminoacyl‐β‐naphthylamide substrates was found using alanine‐, arginine‐, leucine‐ and lysine‐β‐naphthylamide. There was a positive correlation between the recommended concentration of essential amino acids in penaeid shrimp feed and aminopeptidase activity in both sub‐adult stages. Proteolytic activity of F. subtilis was strongly inhibited by specific trypsin inhibitors. The optimal temperature for trypsin, chymotrypsin and leucine aminopeptidase activity was between 45 and 55 °C. Six and seven bands were found in caseinolytic zymograms for SAS6 and SAS13 respectively. All bands were inhibited by phenylmethylsulfonyl fluoride in both sub‐adult stages. The use of tosyl‐lysine‐chloromethyl‐ketone and benzamidine caused strong inhibition of the proteolytic bands. Trypsin and chymotrypsin activity was the main difference observed between the protease pattern of SAS6 and SAS13F. subtilis. 相似文献
264.
Landscape Ecology - Given the importance of spatial heterogeneity in altering dispersal, interspecific interactions, and population persistence, high rates of habitat homogenisation across the... 相似文献
265.
吸胀温度显著地影响甜菜种子的萌发速率。吸胀温度为30℃和20℃时,50%萌发所需要的时间分别为36h和56h;在7℃中吸胀120h,仍未见萌发。在种子吸胀过程中,粗线粒体蛋白的含量,细胞色素C氧化酶和苹果酸脱氢酶的活性增加,且它们在30℃和20℃中的活性较高,在7℃下较低。 相似文献
266.
OBJECTIVE: To determine the infectivity of ovine and caprine strains of Dichelobacter nodosus for both sheep and goats. DESIGN: Pen experiments in which 20 sheep and 19 goats were challenged directly with the two strains, and transmission experiments on pasture, using donors infected by experimental challenge. RESULTS: Sheep and goat strains of D nodosus infected both animal species in experimental challenges. Animals so infected transmitted footrot to both sheep and goats on pasture plots. A significantly smaller proportion of goats than sheep was infected when challenged with either strain. The interval between exposure and development of footrot in goats was longer than in sheep when recipient animals were exposed to infected donors on pasture. The disease was less invasive in goats than in sheep. CONCLUSIONS: With the strains of D nodosus used there was no evidence of host specificity. Direct transmission of footrot can occur between sheep and goats in the same environment. There is a need to include goats in ovine footrot eradication programs and vice versa. 相似文献
267.
Seroepidemiology of undifferentiated fever in feedlot calves in western Canada. 总被引:11,自引:6,他引:5 下载免费PDF全文
C W Booker P T Guichon G K Jim O C Schunicht R J Harland P S Morley 《The Canadian veterinary journal. La revue veterinaire canadienne》1999,40(1):40-48
The relationships between 4 bacterial and 3 viral antibody titers and morbidity (undifferentiated fever (UF)) and mortality were investigated in recently weaned beef calves. Blood samples from 100 animals that required treatment for UF (Cases) and 100 healthy control animals (Controls) were obtained: upon arrival at the feedlot (Arrival), at the time of selection as a Case or Control (Selection), and at approximately 33 d of the feeding period (Convalescent). Seroconversion to Pasteurella haemolytica antileukotoxin was associated with an increased risk of UF (OR = 2.83); however, seroconversion to bovine herpesvirus-1 G-IV glycoprotein was associated with a decreased risk of UF (OR = 0.43). Higher Arrival bovine viral diarrhea virus antibody titer was associated with a decreased risk of UF (OR = 0.83). Increases in Mycoplasma alkalescens antibody titer after Arrival were associated with an increased risk of UF (OR = 1.10). Higher Arrival Haemophilus somnus antibody titer and increases in Haemophilus somnus antibody titer after Arrival were both associated with a decreased risk of UF (OR = 0.76 and OR = 0.78). The odds of overall mortality (OR = 5.09) and hemophilosis mortality (OR = 11.31) in Cases were significantly (P < 0.05) higher than in the Controls. Higher Arrival bovine herpesvirus-1 antibody titer was associated with an increased risk of mortality (OR = 1.30). Protective immunity to Pasteurella haemolytica antileukotoxin, Haemophilus somnus, bovine herpesvirus-1 G-IV glycoprotein, bovine viral diarrhea virus, and Mycoplasma spp. may be necessary to reduce the occurrence of UF. Animals with UF are at an increased risk of overall and hemophilosis mortality. 相似文献
268.
F Hill PB Stark RT Stebbins ER Anderson HM Antia TM Brown TL Duvall DA Haber JW Harvey DH Hathaway R Howe RP Hubbard HP Jones JR Kennedy SG Korzennik AG Kosovichev JW Leibacher KG Libbrecht JA Pintar EJ Rhodes J Schou MJ Thompson S Tomczyk CG Toner R Toussaint WE Williams 《Science (New York, N.Y.)》1996,272(5266):1292-1296
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure. 相似文献
269.
270.
J. C. KEITH JR R. C. WILSON N. H. BOOTH R.J. KEMPPAINEN 《Journal of veterinary pharmacology and therapeutics》1981,4(4):315-316
Apomorphine is derived from morphine by acid hydrolysis (DiChiara & Gessa, 1978), and for many years has been used in both human and veterinary medicine as an effective agent for induction of emesis, primarily in cases of poisoning. Since apomorphine is derived from morphine, it was initially thought that it was an opiate receptor agonist similar to morphine. As a result, several medical and veterinary medical pharmacology textbooks recommend reversal of the emetic activity of apomorphine hydrochloride by administration of naloxone hydrochloride, a narcotic antagonist (Klaassen, 1980; Meyers, Jawetz & Goldfien, 1980). 相似文献