TOC INDEX. Processing Incoming Cattle. Richard Harland. Take Home Messages. Problem

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1 TOC INDEX Processing Incoming Cattle Richard Harland Take Home Messages Start processing as soon as possible following arrival at the feedlot. Follow Quality Assurance Guidelines (refer to Good Production Practices for the feedlot). Processing is the first and best opportunity for the early diagnosis of sick animals. The proper use of implants and dewormers can improve productivity. Mass treatment with injectable long acting antibiotics can reduce disease losses. Vaccination is beneficial, but the vaccination program should be tailored to the type of cattle. Problem Processing of incoming cattle is the collection of procedures and treatments given to cattle as they are worked in the chute and cattle squeeze. It is the first opportunity at the feedlot to impact on the health and performance of the cattle. Many successful processing strategies have been developed to reduce disease and promote the health and performance of incoming cattle. Unfortunately, processing often takes place at the busiest time of the year in the feedlot and since it is repetitious, it is sometimes delegated to the least experienced workers. Careful attention to details and the adoption of a good processing program can get incoming cattle off to a successful start in the feedlot. Disease in the feedlot occurs very soon after arrival. In some studies in Alberta feedlots (1,2) many of the calves were sick in the first week after arrival in the feedlot. For processing to be effective, it must be done as soon as possible following arrival at the feedlot. The sooner cattle are processed and moved to their home pens, the sooner animals can settle in and the sooner the preventive health procedures can take effect. Some people have suggested that it is better to split up the processing procedures to reduce stress. Current thinking is that Alberta Feedlot Management Guide 2E1:1

2 Early Diagnosis and Treatment Metaphylaxis it is less stressful to have all the procedures done at one time then it is to run the cattle through the chute a second time. Generally, it is recommended to process the calves within hours of arrival at the feedlot if possible. Remember, it may have already been several days since the calves left home. Disease can occur soon after arrival in the feedlot and most of the Bovine Respiratory Disease (BRD) cases which die will get sick first during 2 weeks post arrival(3). Fall weaned calves purchased in auction markets often break with disease in the first few days after arrival and the peak number of treatments in a group can be as early as 7 days after arrival. It is obvious that some of these calves are already sick when they arrive at the feedlot. Finding these sick calves in the feedlot pens during the first few days is difficult, because the calves have not settled in yet and most of them are not eating properly. These high risk calves can be checked for early signs of disease during processing by checking their temperature with an electric thermometer. A cutoff temperature can be set (often F or 40.0 C), and any calf with a temperature greater than the cutoff temperature can be treated with the same antibiotic treatments as a regular shipping fever case. Treatment records should be started for these animals at this time. In one feedlot, calves with temperatures greater than F (40.0 C) on arrival had approximately 9 times the chance of dying and 2 times the chance of being pulled for treatment when compared to calves that had temperatures less than F (4). Early identification and treatment of these sick calves is the best procedure to reduce BRD losses. Other disease problems should be noted at this time and treatment initiated. Groups of incoming calves with many animals with high temperatures should be investigated with the cattle buyer, to help identify potential problem sources of cattle. Metaphylaxis is the term used for the mass treatment with a long-acting antibiotic to a group of animals. Both long-acting oxytetracycline (2) and tilmicosin (5) have been tested and shown to be effective when used at processing in Alberta feedlots. An analysis and review of many different trials (6) supports the use of long-acting oxytetracycline and tilmicosin at processing for high risk calves. It is not known if these antibiotics are working through the early treatment of cases or by preventing cases from occurring. Although the cost of a Alberta Feedlot Management Guide 2E1:2

3 metaphylaxis program can seem expensive, reduction in mortality, treatments and increased feed efficiency (tilmicosin) can make these programs cost effective. The decision to use a metaphylaxis program will involve estimating the anticipated cost of disease and performance reduction versus the cost of the metaphylaxis program. Consultation with your herd veterinarian, may help you establish when a metaphylaxis program is most profitable in your feedlot. Vaccination Vaccination helps animals build their own immunity to a disease. Animals will not build a full immune response for several weeks following vaccination. This delay in immune response is one reason that vaccines do not always work as well as they should in feedlot cattle. If cattle are purchased directly from the farm, a vaccination program on the farm (preimmunization) should be arranged before the cattle arrive at the feedlot. This will ensure that the cattle have had a chance to develop their immunity prior to being exposed to disease at the feedlot. If cattle cannot be immunized prior to arrival at the feedlot, they should be vaccinated at processing, so that they have an immunity as soon as possible. The exact vaccination program will vary with the type of cattle and the feedlot. Different disease problems occur in different areas and require different vaccination programs. Almost all types of cattle entering a feedlot are at risk of developing infectious bovine rhinotracheitis (IBR). The modified-live-virus vaccines for IBR give some protection following a single vaccination. Cattle kept for more than 90 days may benefit from a second vaccination around 90 days post arrival to ensure that they are protected for the duration of the feeding period. Intranasal and killed IBR vaccines are also available, but they do not give the same level of immunity, and they should only be used in the feedlot under special circumstances (7). Other viral diseases include bovine virus diarrhea (BVD), bovine respiratory syncytial virus (BRSV) and parainfluenza-3 virus (PI3). These other vaccines are available if these diseases are a problem in your feedlot. Clostridial vaccines have been part of the standard vaccination protocol for cattle entering feedlots for years. These vaccines are available from single to 8 way combinations of different Clostridial organisms. Clostridial vaccines especially those including Clostridium perfringens Types C & D have been associated with the development of injection site reactions and carcass damage. These vaccines Alberta Feedlot Management Guide 2E1:3

4 should be administered subcutaneously to avoid carcass damage. The total number of doses of Clostridial vaccines sold is enough to vaccinate every animal more than 2 times a year, which would indicate that some calves are being vaccinated more often than necessary. Since these vaccines can cause reactions, unnecessary Clostridial vaccinations should be avoided. The increasing use of rubber bands for castration has increased the incidence of tetanus in some feedlots. Feedlots using this method of castration should use a Clostridial vaccine that includes Clostridium tetani toxoid. Pasteurella haemolytica, Haemophilus somnus and Pasteurella multocida are bacteria that have been associated with feedlot mortality. Vaccines are available for these diseases and field tests in western Canada of some of these products indicate that they can be useful in reducing disease losses associated with these organisms (1, 8, 9, 10). The value of these vaccines in your preventative health program will depend on the level of disease, the type of cattle fed, and other preventative measures used. There are many different vaccines and new vaccine information available. Your local herd veterinarian should be contacted to recommend the best vaccination program for your feedlot. Enhancing Performance Implants have been widely accepted for the improvement of average daily gain and feed/gain efficiency. The first implants were first introduced in the 1950 s and newer products have been introduced since that time. It is important that implants be administered properly to be effective. A survey in midwestern and southwestern U.S. feedlots indicates that 15% of implants are incorrectly placed. Improperly placed implants can result in more than $20.00 of lost productivity per animal (11). Proper training, cleanliness and restraint of cattle is important for the correct, safe and efficacious placement of implants. Implants should be selected to match the type of cattle on feed and the duration of the feeding period. Reimplantation is usually necessary for cattle kept for longer periods. Traditionally the problem of internal worms (nematodes and cestodes) was not considered to be as important in Alberta as other areas of North America. As a result dewormers (anthelminthics) were not as widely used in Alberta as elsewhere. One Alberta field study shows that the use of a dewormer can cost effectively improve productivity in feedlot cattle (12). Several different products and product Alberta Feedlot Management Guide 2E1:4

5 Additional Processing Procedures Facilities and Equipment combinations are available for use in feedlot calves. The label instructions should be followed closely to deliver the correct dose by the appropriate route. Some of these products will take care of warbles and lice as well as internal worms. Other dewormers will still require the use of a separate product to control warbles or lice. Other products have been given to enhance health and productivity, although the efficacy of these products has not been clearly demonstrated. Typically most cattle get vaccinated with Vitamin A and D. While this is appropriate when the diet is deficient, there is no evidence to support its widespread use in the feedlot. Generally we should try to administer vitamins in an appropriately balanced ration rather than by injection. There is even less evidence for the routine use of other vitamin combinations. During processing most animals are given some form of identification. Hot iron branding is the traditional method of identifying the ownership of groups of cattle. However branding does reduce the value of the hide and should be avoided if possible. Individually numbered eartags are useful for cattle identification and are the basis for a good health and drug residue avoidance record system. Ideally all cattle entering a feedlot should be individually identified. If this is not possible, than each sick animal that is individually treated with a drug should be individually identified to prevent the shipping of drug contaminated animals. Surgical castration of bull calves during the initial processing adds additional health risks and stresses to incoming cattle. It is better to wait until a later date when there are fewer other health problems. The newer rubber band or elastrator methods of castration can be used successfully at the time of initial processing. Abortion programs for heifers can also be quite stressful and include additional health risks. These abortion programs are best reserved for later in the feedlot period when it is easier to pregnancy check the heifers, induce abortions and monitor their health. Good handling facilities are very important to successful processing. The right facilities can improve the number animals processed per hour without reducing the quality of processing. Poor facilities increase frustration and stress for staff and cattle. Poor facilities also increase the risk of injuries Alberta Feedlot Management Guide 2E1:5

6 to cattle and make them more reluctant to enter the chute a second time. The proper administration of drugs and vaccines requires a clean work bench or counter top. This provides a clean place to place syringes and needles between animals, and easy access to bottles to refill syringes. Clean syringes and fresh needles will limit the potential for adverse reactions to injections. Processing procedures are an important part of the quality assurance program. All drugs should be used according to label directions and the subcutaneous route should be used if the label directions permit. Records should be started for all animals entering the feedlot and all treatments that have been given should be recorded. Conclusion Processing is the most important first step in the control of disease and improving production in feedlot animals. It provides a unique opportunity to diagnose, treat and prevent disease. Proper processing procedures can enhance productivity. Careful planning, proper facilities and clean equipment are essential to an effective processing program. References 1. Ribble, C.S., Jim, G.K., Janzen, E.D. Efficacy of a immunization of feedlot calves with a commercial Haemophilus somnus bacterin. Can Vet J 1988; 52: Harland, R.J., Jim, G.K., Guichon, P.T., Townsend, H.G.G., Janzen, E.D. Efficacy of parenteral antibiotics for disease prophylaxis in feedlot calves. Can Vet J 1991; 32: Ribble, C., Van Donkersgoed, J., Harland, R.J. and Janzen, E.D. Using epidemiology as an aid in feedlot disease management. Proceedings 24th Annual Conference of American Association of Bovine Practitioners. Orlando, Florida. September Harland, R.J. Evaluation of the association between bovine respiratory disease and fever on arrival in feedlot calves. Proceedings of Conference of Research Workers in Animal Disease. Chicago Ill. Nov. 5 th Mork, D.W., Merrill, J.K., Thorlackson, B.E., Olson, M.E., Tonkinson, L.V., Costerton, W. The prophylactic efficacy of timicosin for respiratory disease. J Am Vet Med Assoc Van Donkersgoed, J. Meta-analysis of field trials of antimicrobial mass medication for prophylaxis of bovine respiratory disease in feedlot cattle. Can Vet J 1992; 33: Van Donkersgoed, J., van den Hurk, J., McCartney, D., Harland, R.J. Comparative serlogical responses in calves to eight commercial vaccines against infectious bovine rhinotracheitis, parainfluenza-3, bovine respiratory syncytial, and bovine viral diarrhea viruses. Can Vet J 1991; 32: Jim, K., Guichon, T., Shaw, G. Protecting calves from pneumonic pasteurollosis. Vet Med 1988; 83: Van Donkersgoed, J., Schumann, F.J., Harland, R.J., Potter, A.A., Janzen, E.D. The effect of route and dosage of immunization on the serological response to a Pasteurella haemolytica and Haemophilus somnus vaccine in feedlot calves. Can Vet J 1993; 34: Alberta Feedlot Management Guide 2E1:6

7 10. Harland R.J., Potter A.A., van Drunen-Little-van den Hurk, S., Van Donkersgoed, J., Parker, M.D., Zamb, T.J., Janzen, E.D. The effect of subunit or modified live bovine herpesvirus-1 vaccines on the efficacy of a recombinant Pasteurella haemolytica vaccine for the prevention of respiratory disease in feedlot calves. Can Vet J. 1992; 33: Lehman, F.D, Rains, J.R. Implants: A valuable tool for the cattle-feeding industry. Comp Cont Edu (Food Animal) 1996; 18(8):S174-S Bauck, S.W., Jim, G.K., Guichon, P.T, Newcomb, K.M., Cox, J.L., Barrick, R.A. Comparative cost-effectiveness of ivermectin versus topical organophosphate in feedlot cattle. Can Vet J 1989; 30: Alberta Feedlot Management Guide 2E1:7