Genetic Characterization of a New U.S. Bovine Rotavirus Isolate

We have identified a new group A rotavirus associated with diarrheic calves in the field. The VP7 gene of this virus (designated VMRI-29), appears to differ genetically from that of the reference strain NCDV-Lincoln. Studies are underway to determine the importance of this genetic variant in the etiology of rotavirus-induced calf diarrhea.

Prebreeding Immunization of Beef Cows

A number of infectious agents are potential threats to the fetus of a pregnant cow and may result in abortion. These agents include Leptospira sp., Campylobacter fetus and viruses such as infectious bovine rhinotracheitis (IBR) and bovine virus diarrhea (BVD). Maintenance in the cow of a high level of immunity to these agents during pregnancy can insure protection of the fetus. In particular, vaccines against BVD and IBR viruses can establish protective immunity throughout gestation. An appropriate vaccination regimen prior to breeding is required to establish this protective immunity. This can be achieved with a single dose of certain modified live virus vaccines, but those vaccines must be administered at least 30 days prior to breeding to avoid interference with conception. We have evaluated an oil-adjuvanted inactivated virus vaccine in cattle with differing immunological histories. Two doses of the vaccine administered 30 days apart to serologically negative animals induced appreciable levels of BVD and IBR anti-viral antibodies with persisting titers throughout gestation. In other experiments a single dose of the vaccine was administered to: (1) animals given two doses of the vaccine several months earlier, (2) animals previously vaccinated with other inactivated virus vaccines, or (3) animals previously vaccinated with modified live virus vaccine. The vaccine consistently induced marked anamnestic responses in these animals. Not only did mean titers rise, but a vast majority of individual animals responded. This contrasts with efforts to boost titers with modified live virus vaccines where the effect may be erratic among animals. The safety and efficacy of selected inactivated viral vaccines argues for their use in prebreeding immunization of beef cows.

Proceedings of the Fifteenth Annual biochemical Engineering Symposium

This work represents the proceedings of the fifteenth symposium which convened at Colorado State University on May 24, 1985. The two day meeting was scheduled one month later than usual, i.e., after the spring semester, so that travelers from the Midwest (Iowa State University, Kansas State University and University of Missouri) could enjoy the unique mountain setting provided at Pingree Park. The background of the photograph on the cover depicts the beauty of the area. ContentsGreg Sinton and S.M. Leo, KSU. Models for the Biodegration of 2.4-D and Related Xenobiotic Compounds. V. Bringi, CSU. Intrinsic Kinetics from a Novel Immobilized Cell CSTR. Steve Birdsell, CU. Novel Microbial Separation Techniques. Mark Smith, MU. Kinetic Characterization of Growth of E. coli on Glucose. Michael M. Meagher, ISU. Kinetic Parameters of Di- and Trisaccharaide Hydrolysis by Glucoamylase II. G.T. Jones and A.K. Ghosh Hajra, KSU. Modeling and Simulation of Legume Modules with Reactive Cores and Inert Shells. S.A. Patel and C.H. Lee, KSU. Energetic Analysis and Liquid Circulation in an Airlift Fermenter. Rod R. Fisher, ISU. The Effects of Mixing during Acid Addition of Fractionally Precipitated Protein. Mark M. Paige, CSU. Fed-batch Fermentations of Clostridium acetobutylicum. Michael K. Dowd, ISU. A Nonequilibirium Thermodynamic Description of the Variation of Contractile Velocity and Energy Use in Muscle. David D. Drury, CSU. Analysis of Hollow Fiber Bioreactor Performance for MAmmalian Cells by On-Line MMR. H.Y. Lee, KSU. Process Analysis of Photosynthetic Continuous Culture Systems. C.J. Wang, MU. Kinetic Consideration in Fermentation of Cheese Whey to Ethanol.

Characterizing Overall Response to Two-shot Vaccination for BVDV Type 2 in Angus Weanling Calves

Vaccination is a management strategy utilized to help reduce prevalence of bovine respiratory disease in feedlots. However, not all animals respond similarly to vaccinations. It is believed that an animal’s genetics control part of the ability to respond to a vaccination protocol. In order to evaluate the genetic control of a new trait such as response to vaccination, it is important to understand the non-genetic factors that affect an animal’s response to vaccination. The objective of this study was to characterize the non-genetic factors affecting overall response to a two-shot vaccination for bovine viral diarrhea virus type 2 (BVDV2) in Angus weanling calves.