Refinar búsqueda
Resultados 51-60 de 148
In vitro lymphocyte proliferative responses and gamma-interferon production as measures of cell-mediated immunity of cattle exposed to Pasteurella haemolytica
1996
DeBey, B. M. | Roth, J. A. | Brogden, K. A. | Cutlip, R. C. | Stevens, M. G. | Jones, T. | Briggs, R. E. | Kluge, J. P.
Cell-mediated immune mechanisms may play a role in the pathogenesis and prevention of pneumonia in cattle caused by Pasteurella haemolytica serotype A1. To determine the circumstances required to stimulate and identify cell-mediated immune responses, calves were vaccinated with a commercial P. haemolytica bacterin or a live commercial P. haemolytica vaccine, or were infected intratracheally with virulent P. haemolytica. All calves were challenge-exposed intratracheally with P. haemolytica 31 d after vaccination or prior infection. Peripheral blood mononuclear cells and mediastinal and superficial cervical lymph node cells were stimulated with antigens prepared from P. haemolytica to evaluate in vitro proliferative responses and gamma-interferon production as measures of cell-mediated immunity. Strong proliferative responses and gamma-interferon production were detected in lymph node cells from calves vaccinated with the live vaccine and from infected calves, especially in response to stimulation with an outer membrane protein preparation from P. haemolytica. Greater proliferative responses and gamma-interferon production were associated with the lymph node nearer the site of bacterin administration (superficial cervical lymph node) or the site of infection (mediastinal lymph node), whereas greater proliferative responses and gamma-interferon production were associated with the more distant lymph node (mediastinal lymph node) in calves vaccinated with the live vaccine. Neither proliferative responses nor gamma-interferon production were detected in peripheral blood mononuclear cells from calves that were vaccinated for or infected with P. haemolytica. Antileukotoxin antibody titers were determined by a serum neutralization assay, and protection against pneumonic lesions was more closely correlated with antileukotoxin antibody responses than with lymphocyte proliferation or gamma-interferon responses.
Mostrar más [+] Menos [-]Use of a mix of lidocaine and butorphanol as a caudal epidural anesthesia in a mare
1996
Csik-Salmon, J. | Blais, D. | Vaillancourt, D. | Garon, O. | Bisaillon, A.
Loss of rear motor control is the main limiting factor in the use of caudal epidural anesthesia in the horse. In man and laboratory animals, a small dose of an opiate combined with a local anesthetic enhances analgesia without impairing motor function. Thus, the amount of local anesthetic administered may be reduced. Butorphanol is an opiate widely used in horses. It has a good margin of safety and few cardiorespiratory effects. The effects of lidocaine (0.25 mg/kg) and lidocaine-butorphanol (0.25 mg/kg, and 0.04 mg/kg, respectively) were compared in 2 groups of 5 healthy unsedated mares. Horses in each group received either lidocaine or lidocaine-butorphanol in saline solution for a total volume of 0.0165 mg/kg. Epidural injection was performed at the first coccygeal interspace. Each mare was used only once. Cutaneous analgesia was assessed by a response to a pin prick; and visceral analgesia was assessed by response to a noxious stimulus applied to the urethra. Heart rate, respiratory rate, and arterial blood pressure were also measured. Analysis of the results showed an increase in duration of both cutaneous and visceral analgesia in the mares given lidocaine-butorphanol. Cutaneous analgesia increased from 36 +/- 13 to 150 +/- 21 min and visceral analgesia increased from 22 +/- 10 to 162 +/- 16 min. A cranial extension of the cutaneous analgesia was also observed. Cardiorespiratory depression or signs of excitation were not observed. However, these mares demonstrated peculiar walking in the hind limbs, not associated with signs of ataxia or hyperkinesia.
Mostrar más [+] Menos [-]Psychodemographic profile of stockpeople working on independent and integrated swine breeding farms in Quebec
1996
Ravel, A. | D'Allaire, S. | Bigras-Poulin, M. | Ward, R.
As a part of a larger study, the psychodemographic profile of Quebec pig stockpeople was described based on a sample of 48 persons working on independent farms randomly selected in the Richelieu-Saint-Hyacinthe region, and on a convenience sample of 38 others employed by 5 organizations of integrated swine production chosen among the largest ones in Québec. The 2 groups of stockpeople were described separately because of the differences between the 2 types of production. Demographic data (age, sex, level of education, training and experience in swine production, seniority on the farm) were obtained through a face-to-face interview. The personality profile was assessed using a standard personality test (French translation of the Sixteen Personality Factor Questionnaire). Both the stockpersons on independent farms and those employed by the organizations were more reserved, emotionally stable, serious, conscientious, unsentimental, controlled, introverted, and less anxious than the average person in the general population. However, multivariate analyses revealed some differences between these two groups of stock-persons (P = 0.021) as well as between the employees of the different organizations (P = 0.0038). These differences in personality profiles may reflect differences in working conditions, particularly regarding the human relationships, and in corporate cultures of the organizations.
Mostrar más [+] Menos [-]The efficacy of a Giardia lamblia vaccine in kittens
1996
Olson, M. E. | Morck, D. W. | Ceri, H.
Twenty kittens were vaccinated with a Giardia lamblia vaccine prepared on a commercial scale on day 0 and boosted on day 21 (group 1); while 10 kittens received only saline (group 2). These kittens were challenged on day 35 with 10(6) Giardia lamblia trophozoites by a surgical intraduodenal injection. Three control kittens were not vaccinated and not challenged (group 3). Following challenge, Giardia vaccinated kittens had significantly fewer days in which abnormal stools were observed and reduced food intake occurred compared to saline injected animals. The rate of weight gain between group 1 and group 2 animals was not different in the prechallenge period (day 0 to day 35), but vaccinated animals had a significantly higher weight gain in the postchallenge period (P < 0.05). On day 56, all vaccinated animals were not passing cysts in their feces, while 40% of saline injected kittens had Giardia cysts in their feces. In vaccinated kittens, cysts were never demonstrated in 45% of the animals, while cysts were detected in 90% of the saline injected kittens. Viability of the cysts in vaccinated kittens was 38% while the cysts viability in saline injected kittens was 99%. On postmortem examination, trophozoites could be detected in 5% of vaccinated kittens and 60% of saline injected kittens. Vaccination produced an elevated Giardia specific serum IgG and IgA response prior to challenge and throughout the postinfection period. The Giardia infection in the saline injected group did not induce an elevated specific serum response. Giardia vaccination of kittens provides protection in kittens from an experimental challenge by reducing or eliminating intestinal trophozoites and fecal cyst excretion.
Mostrar más [+] Menos [-]Development of a laboratory animal model of postoperative small intestinal adhesion formation in the rabbit
1996
Singer, E. R. | Livesey, M. A. | Barker, I. K. | Hurtig, M. B. | Conlon, P. D.
In order to establish a model of postoperative intestinal adhesions that would simulate the problem experienced in horses, New Zealand White rabbits were utilized to compare two models of adhesion formation that had been successful in the horse, an ischemic strangulating obstruction (ISO) model and a serosal scarification model. An untreated control group was compared with animals subjected to 1, 2, 3 and 4 h periods of ISO, and to serosal scarification. At postmortem examination 14 d postoperatively, the number of rabbits in each group with adhesions was recorded. Serosal scarification was significantly more consistent at producing adhesions than ISO (Fisher's exact test, P = 0.0022). The 3 h of ISO group was significantly different from the control group: however, compared to the serosal scarification group, fewer animals had adhesions and one animal died of complications associated with the experimental procedure. Based on these results, serosal scarification was selected as the best model for utilization in further studies of adhesion prevention.
Mostrar más [+] Menos [-]Changes of serum cytokine activities and other parameters in dogs with experimentally induced endotoxic shock
1996
Miyamoto, T. (Hokkaido Univ., Sapporo (Japan)) | Fujinaga, T. | Yamashita, K. | Hagio, M.
Immunomodulative effects of bovine immunodeficiency-like virus (BIV)-infection and mixed infection of BIV and bovine leukemia virus on sheep
1996
Hirai, N. (Hokkaido Univ., Sapporo (Japan)) | Kabeya, H. | Ohashi, K. | Sugimoto, C. | Onuma, M.
African swine fever in Zambia: Potential financial and production consequences for the commercial sector
1996
Samui, K.L. (University of Zambia, Lusaka) | Nambota, A.M. | Nweene, A.S. | Onuma, M.
Viral diseases of livestock in Zambia
1996
Mweene, A.S. (Hokkaido Univ., Sapporo (Japan)) | Pandey, G.S. | Sinyangwe, P. | Nambota, A.M. | Samui, K.L. | Kida, H.
Detection of viral genome in non-neural tissues of cattle experimentally infected with bovine herpesvirus 1
1996
Mweene, A.S. (Hokkaido Univ., Sapporo (Japan)) | Okazaki, K. | Kida, H.