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981.
H. Patricia Escamilla M. Jos Juan Martínez C. Mario Medina S. Elizabeth Morales 《Canadian journal of veterinary research》2007,71(4):314-317
The objective of this study was to determine the frequency of infectious bovine abortion and to identify some of its causes, specifically brucellosis, leptospirosis, bovine viral diarrhea, infectious bovine rhinotracheitis, and neosporosis. The study was carried out in a dairy herd in the state of Queretaro, Mexico, between September 2002 and March 2003. At the beginning of the study, blood samples were taken from a random 33% of the 300 lactating or pregnant cows; antibodies against Leptospira interrogans were the most commonly identified, in 91% of the 99 samples. Blood samples were also taken 14 to 28 d after the 26 subsequent abortions in the herd in the 6-mo study period, as well as from 22 cows that had not aborted within 5 d after the abortions in the other group. Seroconversion was most frequent for L. hardjo, occurring in 8 (67%) of the 12 dams that aborted after the initial serologic sampling and for which paired serum samples were therefore available. Of the 16 collected fetuses, 10 had histologic lesions suggesting infection in various organs, the features correlating with the serologic results for the dams in 7 cases. Thus, the abortions may have been caused by more than 1 infectious agent. 相似文献
982.
Juvenal Kanani Dirk Philipp Kenneth P Coffey Elizabeth B Kegley Charles P West Shane Gadberry John Jennings Ashley N Young Robert T Rhein 《畜牧与生物技术杂志(英文版)》2015,6(1)
Background
The effect of time of fecal sampling on the accuracy of acid-detergent insoluble ash (ADIA) and alkaline-peroxide lignin (APL) for the prediction of fecal output (FO) in cattle was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 bermudagrass [Cynodon dactylon (L.) Pers.] hay diets markedly different in crude protein concentration (79–164 g/kg) with 2 replicates per diet for 3 periods. Cows were offered hay individually at 20 g DM/kg of body weight daily in equal feedings at 08:00 and 16:00 h for a 10-d adaptation period followed by 5-d of total fecal collection. Fecal grab samples also were taken each day during the fecal collection period at 06:00, 12:00, 18:00, and 24:00 h either directly from the rectum or from freshly voided feces. Samples were composited within cow and time across the 5 d total fecal collection period. Additionally, forage, ort, and fecal samples were analyzed for concentrations of APL and ADIA.Results
Fecal concentrations of ADIA and APL were not affected by sampling time (P ≥ 0.22), even though diet affected (P < 0.01) fecal ADIA and APL concentrations. There were no diet × sampling time interactions (P ≥ 0.60). Estimates of FO and dry matter digestibility (DMD) from ADIA and APL were not affected (P ≥ 0.16) by sampling time or the diet × sampling time interaction (P ≥ 0.74). Estimates of FO and DMD from markers from different sampling times or all different combinations of sampling time were not different (P ≥ 0.72) from those of total collection among internal markers.Conclusion
Little variation in concentrations of ADIA and APL in daily fecal excretion across time increases flexibility in fecal grab sampling schedules for predicting FO and DMD. 相似文献983.
984.
Elizabeth A. Cates Erin E. Connor David M. Mosser Douglas D. Bannerman 《Comparative immunology, microbiology and infectious diseases》2009,32(6):477-490
Mastitis is a prevalent disease in dairy cows. Gram-negative bacteria, which express the pro-inflammatory molecule lipopolysaccharide (LPS), are responsible for the majority of acute clinical cases of mastitis. Previous studies have identified differential susceptibility of human and bovine endothelial cells (EC) to the pro-inflammatory and injury-inducing effects of LPS. The Toll-like receptor (TLR)-4 signaling pathway, which is activated by LPS, has been well studied in humans, but not in ruminants. Human myeloid differentiation-factor 88 (MyD88) and TIR-domain containing adaptor protein (TIRAP) are critical proteins in the LPS-induced NF-κB and apoptotic signaling pathways. To assess the role of the bovine orthologs of these proteins in bovine TLR-4 signaling, dominant-negative constructs were expressed in bovine EC, and LPS-induced NF-κB activation and apoptosis evaluated. The results from this study indicate that bovine MyD88 and TIRAP play functional roles in transducing LPS signaling from TLR-4 to downstream effector molecules involved in NF-κB activation, and that TIRAP promotes apoptotic signaling. 相似文献
985.
Elizabeth A Leece BVSc CertVA Diplomate ECVAA MRCVS Nicolas M Girard† DVM CertVA MRCVS & Kieren Maddern BVSc MACVSc MRCVS 《Veterinary anaesthesia and analgesia》2009,36(5):480-484
Objective To evaluate the induction and maintenance of anaesthesia using alfaxalone following pre-anaesthetic medication with romifidine and butorphanol in ponies undergoing castration in the field.
Study design Prospective clinical study.
Animals Seventeen male ponies weighing 169 ± 29 kg.
Methods The ponies were sedated with romifidine and butorphanol intravenously (IV). Induction time was recorded following administration of alfaxalone 1 mg kg−1 and diazepam 0.02 mg kg−1 IV. If movement during surgery occurred, alfaxalone 0.2 mg kg−1 was administered IV. The quality of anaesthetic induction, and recovery were scored on a subjective scale of 1 (good) to 5 (poor). The number of attempts to attain sternal recumbency and standing, quality of recovery and times from induction to end of surgery, first head lift, sternal recumbency and standing were recorded.
Results Induction quality was good [median score (range) 1 (1–3)] with a mean ± SD time of 29 ± 6 seconds taken to achieve lateral recumbency. Ten ponies required incremental doses of alfaxalone during surgery. Mean times to the end of surgery, first head lift, sternal recumbency and standing were 26 ± 9 minutes, 31 ± 9 minutes, 33 ± 9 minutes and 34 ± 9 minutes respectively. The number of attempts to attain sternal recumbency was 1(1–1) and to attain standing was 1(1–2). Quality of recovery was good, with a recovery score of 1(1–2).
Conclusions and clinical relevance Alfaxalone provided smooth induction and recovery characteristics and was considered suitable for maintenance of anaesthesia for castration in ponies. 相似文献
Study design Prospective clinical study.
Animals Seventeen male ponies weighing 169 ± 29 kg.
Methods The ponies were sedated with romifidine and butorphanol intravenously (IV). Induction time was recorded following administration of alfaxalone 1 mg kg
Results Induction quality was good [median score (range) 1 (1–3)] with a mean ± SD time of 29 ± 6 seconds taken to achieve lateral recumbency. Ten ponies required incremental doses of alfaxalone during surgery. Mean times to the end of surgery, first head lift, sternal recumbency and standing were 26 ± 9 minutes, 31 ± 9 minutes, 33 ± 9 minutes and 34 ± 9 minutes respectively. The number of attempts to attain sternal recumbency was 1(1–1) and to attain standing was 1(1–2). Quality of recovery was good, with a recovery score of 1(1–2).
Conclusions and clinical relevance Alfaxalone provided smooth induction and recovery characteristics and was considered suitable for maintenance of anaesthesia for castration in ponies. 相似文献
986.
Acute phase proteins in dogs naturally infected with the Giant Kidney Worm (Dioctophyme renale) 下载免费PDF全文
987.
Lisa M. Freeman DVM PhD DACVN Maureen A. McMichael DVM DACVECC Armelle M. de Laforcade DVM DACVECC Elizabeth A. Rozanski DVM DACVECC DACVIM Donald J. Brown DVM PhD John E. Rush DVM MS DACVECC DACVIM 《Journal of Veterinary Emergency and Critical Care》2003,13(2):71-76
Objective: To determine nitric oxide concentration in cats with hypertrophic or intermediate forms of cardiomyopathy and arterial thromboembolism (ATE) compared to healthy controls and to determine the association between nitric oxide concentration and the presence of ATE, congestive heart failure (CHF), and echocardiographic measurements. Design: Case–control study. Setting: Veterinary teaching hospital. Animals: Client‐owned cats with cardiomyopathy, cardiomyopathy and ATE, and normal cats. Interventions: None. Measurements: All cats underwent 2‐dimensional and M‐mode echocardiography. Nitric oxide was assessed indirectly by measuring the concentration of plasma nitrite+nitrate (NN), end products of nitric oxide metabolism. Plasma arginine concentration and dietary arginine content were also assessed since arginine is a precursor for nitric oxide production. Main results: Twenty‐six cats with cardiomyopathy, 26 cats with cardiomyopathy and ATE, and 29 nor‐mal cats were enrolled. Compared with healthy controls, median NN concentration was significantly higher in cats with cardiomyopathy and cats with both cardiomyopathy and ATE. There was no difference between cats with cardiomyopathy alone and cats with cardiomyopathy and ATE. Nitrate+ nitrite concen‐tration in cats with cardiac disease was unrelated to the presence of CHF, plasma arginine concentration, or dietary arginine content. In cats with cardiac disease, the left atrial diameter, left ven‐tricular diameter in diastole, and age were negatively correlated with NN concentrations. Conclusions: Nitric oxide concentration is elevated in cats with cardiac disease, but the elevation appears to be independent of ATE and CHF. 相似文献
988.
Gretchen L. Schoeffler DVM Elizabeth A. Rozanski DVM DACVECC DACVIM John E. Rush DVM MS DACVECC DACVIM 《Journal of Veterinary Emergency and Critical Care》2001,11(2):147-152
Objective: To report a case of pyothorax in a critically ill canine neonat.
Case Summary: A12-day old, female boxer puppy was presented for lethargy, fever and respiratory distress. Pleural ceffusion was apparent on thoracic radiography. Thoracentesis and subsequent cytology and bacteriologic culture of the Pleural effusion, confirmed a diagnosis of pyothorax. Clinical management of pyothorax in critically ill 12-day- old puppy is decribed
New or Unique information provided: Pyothorax can occur in the caine neonate. J Vet Emerg crit care 2001;11(2): 147–152) 相似文献
Case Summary: A12-day old, female boxer puppy was presented for lethargy, fever and respiratory distress. Pleural ceffusion was apparent on thoracic radiography. Thoracentesis and subsequent cytology and bacteriologic culture of the Pleural effusion, confirmed a diagnosis of pyothorax. Clinical management of pyothorax in critically ill 12-day- old puppy is decribed
New or Unique information provided: Pyothorax can occur in the caine neonate. J Vet Emerg crit care 2001;11(2): 147–152) 相似文献
989.
Elizabeth Keep 《Euphytica》1969,18(2):256-276
Summary Six phenotypically distinct dwarfs of the raspberry (Rubus idaeus L.) are described; two of them are digenic, sturdy dwarf being D
1d1d2d2or d
1d1d2d2and crumpled dwarf d
3d3d4d4. Jennings' (1967) dwdw dwarf appears to be phenotypically and genotypically identical with the digenic sturdy. The genes d
1and d
2are being used in breeding shorter, self-supporting raspberries.Many raspberry cultivars carry dwarfing genes and the following genotypes have been determined:Lloyd George: . d
1D2D2D3D3.d4(or. d
1D2D2 . d3D4D4
Burnetholm: D
1D1D2d2D3D3 . d4(or D
1D1D2d2 . d3D4D4)Pyne's Royal: D
1d1D2d2D3d3 . d4(or D
1d1D2d2 . d3D4d4)Preussen: . d
1D2d2 . d3D4D4 (or . d
1D2d2D3D3 . d4)Newburgh: D
1d1D2d2D3D3 . d4
Malling Promise: . D
1D2d2D3d3d4d4
Other cultivars known to carry these and/or other dwarfing genes are Norfolk Giant, Malling Landmark, Malling Jewel, Baumforth A, Baumforth B and Park Lane.Dwarfing and other widespread semi-lethal genes such as those affecting chlorophyll production are thought to confer a selective advantage through the maintenance of heterozygosity at a wide range of linked loci. The selective advantage would be most marked in crops such as the raspberry where self-compatibility is of recent origin and inbreeding depression is usually severe. 相似文献
990.
Brassica napus somatic hybrids with low linolenic acid (18:3) content in their seed oil have been produced using fusion partners
screened for low 18:3. One somatic hybrid contained only 3.5% 18:3, a level significantly below the mid-parental mean. The
low level of 18:3 proved stable in the R1 generation. Oil content of the lowest 18:3 selection increased from the mid-parental mean (29.3%) in the R0 generation to 36% in a R1 field bulk. The R1 field population also showed some resistance to shattering.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献