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positive aspects of an enterprise and accounts for all the challenges and risks in a business-like manner. Summary All of the resources for feeding cattle in North Dakota are present. People with the passion, business skills, and resources can succeed in this enterprise as there are a number of successful commercial feedyards in North Dakota that serve as examples. The owners, managers, and operators of these yards have been open and instructive in describing their operations. There are a number of education programs to help new and existing livestock producers gain knowledge and more carefully define their enterprises. These include site visits by North Dakota Stockmen’s Association environmental programs director, North Dakota Stockmen’s Association feedlot intern programs, NDSU Feedlot Schools and producer feeder calf finishing projects, North Dakota Farm Business Management Program records analysis, NRCS and North Dakota Stockmen’s Association facilities grant programs, assistance from the North Dakota Department of Agriculture and the North Dakota Department of Commerce, local economic development organizations, and individual assistance from a wide variety of people in the industry. Acknowledgements The author is appreciative of many livestock producers and colleagues in industry and universities that provided input for this paper. Diagnostic Note – Infectious Bovine Keratoconjunctivitis (Pinkeye) N. W. Dyer NDSU Veterinary Diagnostic Laboratory Moraxella bovis is the primary known cause of infectious bovine keratoconjunctivitis or pinkeye, the most important ocular disease of cattle worldwide. It is most commonly seen in the warmer months. While the disease is not a significant cause of mortality, it does cause considerable economic loss due to secondary problems related to corneal ulcers. It is well known that certain risk factors, such as ultraviolet radiation, dust, chaff, grass awns and face flies predispose an animal to pinkeye. Based on recent biochemical analysis, there are fifteen distinct subgroups of this bacteria, some of which are pathogenic and some not. Pathogenic strains possess proteins that allow them to attach to corneal epithelial cells, and cytotoxins that can degrade corneal proteins thus leading to ulcers and the clinical signs associated with them (tearing, sensitivity to light, and conjunctivitis). 6 Commercial vaccines provide protection against only a few pathogenic strains; therefore they will not be 100% effective against disease. Moraxella (now being changed from Branhamella to Moraxella) ovis has also been isolated from cases of pinkeye, but experts do not universally agree that it is a cause of pinkeye. The organism can be isolated from normal bovine eyes as well. Recent research shows that M. ovis produces toxins that degrades bovine red blood cells, white blood cells and corneal epithelial cells, and therefore may play a role in clinical disease. 3 It is not uncommon to isolate M. bovis and M. ovis from cases of pinkeye, suggesting a synergistic effect between the two organisms. Moraxella (formerly Mycoplasma) bovoculi is a recently identified related organism that has been isolated from calves with pinkeye. 2,5 Recent studies indicate that the organism may contribute to Page 54 2009 NDSU Beef Feedlot Research Report
pinkeye, and has been confused with Moraxella ovis. 1 A polymerase chain reaction (PCR) assay to differentiate M. ovis from M. bovoculi was recently developed, and can be performed on presumptive M. ovis isolates at the NDSU-VDL. The problem of cause is further confused by the fact that Moraxella bovoculi can be isolated from normal bovine eyes as well. Recent vaccine trials with an autogenous bacterin to M. bovoculi were unsuccessful in preventing clinical disease in infected groups of calves. 4 This further calls into question the significance of M. bovoculi as a pathogen, and highlights the fact that more information is needed to define this organism as a cause or contributor to pinkeye. Currently, then, M. bovis is the only known cause of pinkeye, and can be isolated from ocular swabs and identified. It is not currently definitively known if M. ovis and M. bovoculi can cause pinkeye, and, while we can culture the organisms, PCR is needed to tell the two apart. There are no commercial vaccines that include protection against M. ovis and M. bovoculi. Autogenous vaccines can be made against these bacteria if isolated, but consulting with your veterinarian is advised when considering the efficacy and administration of such vaccines. From a standpoint of pathogenesis, it seems likely that some sort of trauma or co-infection causes enough damage to the surface of the eye that colonization by resident conjunctival bacteria becomes possible. This would explain why both M. ovis and M. bovoculi can be found in normal eyes, but can also be isolated from diseased eyes. Therefore, the need to differentiate M. ovis from M. bovoculi by PCR needs to be considered on an individual basis by the producer and the practitioner. M. bovis is clearly a cause of pinkeye and it’s recovery from ocular swabs should encourage some combination of management, therapy and vaccination. Consult your veterinarian and diagnostic laboratory with any questions. 1 Angelos J. A., and Louise M. Ball. Differentiation of Moraxella bovoculi sp. nov. from other coccoid moraxellae by the use of polymerase chain reaction and restriction endonuclease analysis of amplified DNA. J Vet Diagn Invest 19:532-534 (2007). 2 Angelos J. A., P.Q.Spinks,L.M. Ball, and Lisle W. George. Moraxella bovoculi sp. nov., isolated from calves with infectious bovine keratoconjunctivitis. Int J of System and Evol Micro 57:789-795 (2007). 3 Cerny H E, D.G.Rogers,J.T. Gray,D.R Smith, and Susanne Hinckley. Effects of Moraxella (Branhamella) ovis cultures filtrates on bovine erythrocytes, peripheral mononuclear cells, and corneal epithelial cells. J of Clin Micro 44:772-776 (2006). 4Funk L.,A.M. O’Connor, M. Maroney,T. Engelken, V.L. Cooper,J. Kinyon and P. Plummer. A randomized and blinded field trial to assess the efficacy of an autogenous vaccine to prevent naturally occurring bovine keratoconjunctivitis (IBK) in beef calves. Vaccine 27:4585-4590 (2009). 5 Levisohn S., S.Garazi, I. Gerchman, and Jacob Brenner. Diagnosis of a mixed mycoplasma infection associated with a severe outbreak of bovine pinkeye in young calves. J Vet Diagn Invest 16:579- 581 (2004). 6 Postma C. G., J.C. Carfagnini, and Leonardo Minatel. Moraxella bovis pathogenicity: An update. Comp Immun Micro and Inf Dis 31:449-458 (2008). Page 55 2009 NDSU Beef Feedlot Research Report
Page 1:
Carrington Research Extension Cente
Page 4 and 5:
Contact Information If you have que
Page 6 and 7: Table of Contents Feedlot Schools A
Page 8 and 9: 6. Grain processing, mixing rations
Page 10 and 11: Table 1. Supplements with and witho
Page 12 and 13: Table 3. Performance of feeder catt
Page 14 and 15: uminal gas cap H2S concentration an
Page 16 and 17: Table 3. Influence of thiamin and s
Page 18 and 19: Table 1. Rations for steers fed inc
Page 20 and 21: Table 3. Carcass traits of cattle f
Page 22 and 23: Table 1. Formulated dietary composi
Page 24 and 25: Table 2. Performance and carcass ch
Page 26 and 27: Effect of Glycerol Level in Feedlot
Page 28 and 29: Receiving Trial Fall 2008 One hundr
Page 30 and 31: Table 3. Heifer body weight average
Page 32 and 33: Impact of Weaning Date on Calf Grow
Page 34 and 35: a 24-hour chill, qualified universi
Page 36 and 37: By design, weaning dates influenced
Page 38 and 39: Thompson, M. M., C. S. Schauer, V.
Page 40 and 41: Diets were formulated to provide re
Page 42 and 43: Marbling number approached signific
Page 44 and 45: Table 1. Finishing ration with 20%
Page 46 and 47: Table 3. Carcass performance of cal
Page 48 and 49: The number of cattle consigned was
Page 50 and 51: The highest combined index score pe
Page 52 and 53: Table 1 Forage Crop Production 2006
Page 54 and 55: Off-quality commodities such as sun
Page 58 and 59: NDSU BBQ Boot Camps 2009 Celebratin
Page 60: NDSU is an equal opportunity instit
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