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104. Effects of various vaccination protocols on passive and active immunity to Pasteurella haemolytica and Haemophilus somnus in beef calves

Author

Van Donkersgoed, J, Guenther, C, Evans, B N, Potter, A A, and Harland, R J

Subjects
Vaccines, Synthetic, Haemophilus Infections, animal diseases, Colostrum, Pasteurella Infections, Vaccination, Haemophilus, Cattle Diseases, Enzyme-Linked Immunosorbent Assay, Antibodies, Bacterial, Injections, Intramuscular, Immunity, Active, Animals, Newborn, Pregnancy, Bacterial Vaccines, Pneumonia, Bacterial, Animals, Cattle, Female, Immunity, Maternally-Acquired, Mannheimia haemolytica, Research Article
Abstract

Two field trials were conducted in a beef cow herd in Saskatchewan to determine the effectiveness of a combined Pasteurella haemolytica and Haemophilus somnus vaccine in increasing passively and actively acquired antibodies in beef calves. Vaccination of dams at 4 and/or 7 weeks prepartum was associated with increased antibody titers to P. haemolytica and H. somnus in their serum (P0.05), colostrum(P0.05), and serum of their calves at 3 days and 1 month of age (P0.05). There was no significant(P0.05) difference in antibody titers in the colostrum and serum of calves from single or double vaccinated dams. Calves vaccinated at 1 and 2 months of age in the face of maternal antibodies toP. haemolytica and H. somnus had significantly(P0.05) higher antibodies to P. haemolytica and H. somnus at 4 and 6 months of age than did unvaccinated calves. Calves vaccinated at 3 and 4 months of age in the face of low levels of preexisting antibodies had significantly (P0.05) higher antibodies toP. haemolytica at 5 months of age and to H. somnus at 5 and 6 months of age than did unvaccinated calves. Calves vaccinated once at 4 months of age had significantly(P0.05) higher antibody titers toP. haemolytica and H. somnus at 4.5 months of age than did unvaccinated calves, but this difference was not apparent at 6 months of age. These results suggest that vaccination of beef cows with a combined Pasteurella haemolytica and Haemophilus somnus vaccine once at 4 weeks prepartum will significantly (P0.05) increase passive antibody titers toP. haemolytica and H. somnus in their calves. Double vaccination of calves with preexisting maternal antibodies at 1 and 2 months of age will increase antibody titers to P. haemolytica and H. somnus until 6 months of age. Vaccination of beef calves with low levels of preexisting antibody at 3 and 4 months of age will increase antibody titers to H. somnus until 6 months of age and to P. haemolytica until 5 months of age.However, the level of antibodies achieved by vaccination may depend on the calves being studied, the level of preexisting antibodies, and the efficiency of passive transfer.

Published
1995

106. The occurrence of Haemophilus somnus in feedlot calves and its control by postarrival prophylactic mass medication

Author

Van Donkersgoed, J, Janzen, E D, Potter, A A, and Harland, R J

Subjects
Lung Diseases, Male, Haemophilus Infections, animal diseases, Prevalence, Animals, Cattle Diseases, Cattle, Oxytetracycline, Pilot Projects, Injections, Intramuscular, Saskatchewan, Research Article
Abstract

Three field trials were conducted in a large commercial feedlot in Saskatchewan to determine the prevalence of Haemophilus somnus in calves and to evaluate the efficacy of prophylactic mass medication with long-acting oxytetracycline on day 17 (1990, n = 1336), day 11 (1991, n = 4372), or day 8 (1992, n = 5632) postarrival. Hemophilosis accounted for > 40% of the mortality in feedlot calves each year. Haemophilus somnus was cultured from the blood of one febrile calf on day 1 (0.1%, n = 895), but it was not cultured from nasal swabs on day 1 or day 11 (n = 881) or from blood samples on day 11 (n = 883). Similarly, it was not cultured from nasal swabs or blood samples from sick calves first treated for bovine respiratory disease (BRD) (n = 219). Serological titers to H. somnus increased (p < 0.05) in unvaccinated calves from day 1 (Geometric mean titer = 11,846) to day 96 (Geometric mean titer = 63,712), indicating natural infection following feedlot entry. Calves that relapsed twice with BRD or died from BRD +/- hemophilosis had significantly (p < 0.06) lower titers to H. somnus on days 1 and 96 than those that did not relapse twice or die. Postarrival mass medication with long-acting oxytetracycline did not reduce (p > 0.05) the risk of hemophilosis mortality. However, it reduced (p < 0.05) the risk of BRD treatment by 14% and the risk of BRD mortality by 71%. Additional epidemiological studies of H. somnus are needed so that we can develop strategic medication and vaccination programs to reduce losses from hemophilosis.

Published
1994

111. Dinoflagellate cyst assemblages as tracers of sea-surface conditions in the northern North Atlantic, Arctic and sub-Arctic seas: the new n = 677 data base and its application for quantitative palaeoceanographic reconstruction

Author

Vernal, A. de, Henry, M., Matthießen, Jens, Mudie, P. J., Rochon, A., Boessenkool, K., Eynaud, F., Grøsfjeld, K., Guiot, J., Hamel, D., Harland, R., Head, M. J., Kunz-Pirrung, Martina, Levac, A., Loucheur, V., Peyron, O., Pospelova, V., Radi, T., Turon, J.-L., Voronina, E., Vernal, A. de, Henry, M., Matthießen, Jens, Mudie, P. J., Rochon, A., Boessenkool, K., Eynaud, F., Grøsfjeld, K., Guiot, J., Hamel, D., Harland, R., Head, M. J., Kunz-Pirrung, Martina, Levac, A., Loucheur, V., Peyron, O., Pospelova, V., Radi, T., Turon, J.-L., and Voronina, E.

Published
2001

117. An early requirement for FGF signalling in the acquisition of neural cell fate in the chick embryo.

Author

Wilson, Sara I, Graziano, E, Harland, R, Jessell, T M, Edlund, T, Wilson, Sara I, Graziano, E, Harland, R, Jessell, T M, and Edlund, T

Abstract

BACKGROUND: In Xenopus embryos, fibroblast growth factors (FGFs) and secreted inhibitors of bone morphogenetic protein (BMP)-mediated signalling have been implicated in neural induction. The precise roles, if any, that these factors play in neural induction in amniotes remains to be established. RESULTS: To monitor the initial steps of neural induction in the chick embryo, we developed an in vitro assay of neural differentiation in epiblast cells. Using this assay, we found evidence that neural cell fate is specified in utero, before the generation of the primitive streak or Hensen's node. Early epiblast cells expressed both Bmp4 and Bmp7, but the expression of both genes was downregulated as cells acquired neural fate. During prestreak and gastrula stages, exposure of epiblast cells to BMP4 activity in vitro was sufficient to block the acquisition of neural fate and to promote the generation of epidermal cells. Fgf3 was also found to be expressed in the early epiblast, and ongoing FGF signalling in epiblast cells was required for acquisition of neural fate and for the suppression of Bmp4 and Bmp7 expression. CONCLUSIONS: The onset of neural differentiation in the chick embryo occurs in utero, before the generation of Hensen's node. Fgf3, Bmp4 and Bmp7 are each expressed in prospective neural cells, and FGF signalling appears to be required for the repression of Bmp expression and for the acquisition of neural fate. Subsequent exposure of epiblast cells to BMPs, however, can prevent the generation of neural tissue and induce cells of epidermal character.

Published
2000

141. System offers on-site generation of sodium hypochlorite

Author

Pond, Harland R.

Subjects
Sodium hypochlorite -- Product information, Business, Business, international, Engineering and manufacturing industries, Environmental services industry
Abstract

For more than 75 years chlorine has been effectively used to disinfect drinking water, eliminating dangerous bacteria and toxic compounds. Water supply engineers and treatment facility operators are used to [...]

Published
2009

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