Developing Herd Health Programs for Cow-Calf Herds

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1 Developing Herd Health Programs for Cow-Calf Herds Mark L. Alley, DVM, MBA North Carolina State University College of Veterinary Medicine Department of Population Health and Pathobiology Raleigh, NC USA Developing herd health programs for cow-calf operations can be time consuming but rewarding for both the producer and the veterinarian if done appropriately. However, many producers think of a herd health program as only a vaccine program. Interestingly, the vaccination schedule and the vaccines that will be used constitute the smallest portion of a true herd health program. If a producer were to use Google as means of determining a herd health program for his/her farm, this producer would find over 95,000 hits describing beef cattle herd health programs. According to all study years of National Animal Health Monitoring Service (NAHMS , veterinarians have been identified by the highest percentage of operations as a very important source of information. Veterinarians were not only considered very important sources for general information, but our profession is also considered to be very important for breeding and genetic information. In the 2007 NAHMS, approximately one-half of all operations consulted a veterinarian for some reason during the previous 12 months, and larger producers (>200 cows had more interactions with veterinarians (82.2% of operations as compared to operations with fewer than 50 cows (43.2%. Economics Veterinarians are in unique position to aid in a farm specific program for the herd. However, it is imperative that the veterinarian understands the goal(s of the producer. Without this understanding of the true goals of the farm, it is impossible to develop a rewarding program that benefits all parties. Where the producer falls on the continuum of whether the operation is only for fun or only for money makes a large difference in how the program should be designed. Research reveals that many factors play a role in the decisions on the farm regarding the adoption of practices identified as best management practices within the industry. These interests/goal such as education of the producer, age of the producer, off farm income as % of total income, size of farm and many others play a critical role, and veterinarians must understand this to effectively aid in developing a herd health plan for farm.

2 Additionally, there are many factors that influence the profitability of the farm. As seen in the chart listed below, veterinary/medicine expenses are rarely the deciding factor as to whether the farm is profitable. However, it does reveal areas where veterinarians must spend some time educating themselves, so we remain a valuable resource for producers. KS Beef Cow-calf Enterprise Returns and Costs, (minimum of three years All High 1/3 Mid 1/3 Low 1/3 Difference between Farms $ / Head $ / Head $ / Head High 1/3 and Low 1/3 Absolute % Gross Income $ $ $ $ $ % Costs Feed $ $ $ $ ($ % Interest $ $94.09 $ $ ($ % Vet Med/Drugs $15.70 $15.85 $15.73 $15.54 $0.30 2% Machinery $66.73 $47.71 $63.34 $88.99 ($ % Labor $92.87 $69.48 $84.90 $ ($ % Other $39.85 $22.85 $35.10 $61.38 ($ % Total Cost $ $ $ $ ($ % Total Return to Mgmt ($ $15.05 ($ ($ $ *Note some costs omitted due to space constraints. Calf sale prices w/i $0.05 and weights w/i 18 # ** Herd information from 65 farms with average herd size of 125 Dhuyvetter, Langemeir 2010 Kansas State Veterinarians will not commonly be seen as expert regarding the categories listed as other or machinery, but veterinarians can play a crucial role in helping with feed costs, labor management, and potentially capital investments (interest. Herd Health As seen in many publications, how healthy a herd is depends on a complex interaction with host (cow or calf, environment, and disease causing organisms. When this triad becomes out of balance, there can be a negative impact on the health of the animal. Fortunately or unfortunately, most of this balance relates directly to appropriate husbandry and management decisions made by the producer and ultimately individuals providing that advice. The ultimate goal of a herd health program is to provide the producer with tools that allow them to quickly and efficiently identify a problem and more importantly prevent that problem from occurring again. Nutrition Nutrition expense on many cow-calf operations can vary from 40 to 70% of total expenses. Some individuals divide the nutrition calendar of a cow into 4 categories. Period 1 is defined as time period immediately post calving and should last for approximately 80 days. Period 2 is defined as when the cow is pregnant and lactating and should last for approximately 125 days. Period 3 is defined as mid gestation. Cows in period 3 are hopefully pregnant and dry (or almost dry depending on weaning age,

3 and it lasts for approximately 110 days. Period 4 is defined as the period of time immediately pre-calving and is approximately 50 days in length. Energy required for fetal growth increases as gestation increases, and the greatest energy requirement is during the last third of gestation. Additionally, daily maintenance requirements of a cow are primarily a function of body weight. Each 100 # increase in cow weight changes the net energy requirements by 6 to 8% which if not managed appropriately will have the greatest negative impact on reproduction. Although veterinarians do not have to be able to balance a ration for an operation, we should all have an understanding of the requirements of cattle in different stages of the production cycle. Differences in Nutrient Requirements Between Various Size Cows with 20# Peak Milk Period 1 Period 2 Period 3 Period Pound Cow (Post-calving (Preg and Lact (Preg and Dry (Pre-Calving TDN(lb CP(lbs Pound Cow TDN(lbs CP(lbs *Adapted from 1996 Nutrient Requirements of Beef One of the best tools available for producers and veterinarians to monitor nutritional status of cattle is the use of body condition scoring. The most common scale used for beef cattle in the US is on a 1 (extremely thin to 9 (obese scale. This scale assumes that each 1 point on the scale is approximately 70 pounds of body weight. If the stage of production is known, a person can approximately calculate how much weight the animal must gain per day to achieve the desired body condition. Relationship of body condition score to beef cow performance and income BCS Preg Rate CI Weaning Age Daily Wean Wt Income/Calf Gain Source: Kunkle et al, 1998; UF With known forage quality and quantity (through hay or pasture analysis, veterinarians can help producers identify the most effective methods and types of supplementation. In general, forages with protein less than 7% results in a reduction of dry matter intake (Mathis, However by supplementing protein to these forage diets, forage intake will increase and may decrease the total amount of nutrients that must be purchased.

4 Average improvement in low-quality forage intake in response to various concentrations of CP Supplemental protein content (% Improvement in forage intake above unsupplemented (% < >30 44 Heldt JS. Supplemental sources on the utilzation of low quality tallgrass-prairie forage (PhD Thesis Kansas State 1998 Feeding frequency is also another area where veterinarians can play a role in reducing labor cost for the farm. Some studies show no decline in performance when changing protein supplementation frequency from daily to every 7 days as long as total supplementation is provided. Findings for energy supplementation frequency have been less definitive for cow-calf operations. Many veterinarians will also be asked about mineral supplementation. Since many suggestions for requirements of herds are geographical specific, I will not try to address those here. However, one common problem many producers find is how best to provide this mineral. This link provides a guide to constructing an inexpensive effective mineral feeder that is easily moved from pasture to pasture. Biosecurity The goal of any biosecurity/biocontainment program is to effectively prevent the entry, increase the resistance, and prevent effective contact when the first two parts of the triad become broken. Unfortunately, beef producers have not been very good at biosecurity due to the nature of the business and tradition of welcoming all individuals to the farm. According to NAHMS 2007, producers are beginning to realize the importance of isolation as shown by 33.7% operations quarantined all or some of the new animals before introduction, but we still have a long way to go. Additionally, 71.3% of operations never used calving area to hold sick cows. For operations that added cattle during the previous 3 years, brucellosis was the most common test identified by participants (24.1% with Johne s (2.1%, BVD (4.5%, Tuberculosis (5.4% being significantly lower. Many operations also had multiple visits per month to their farm with 57.4% of operations reporting greater than one visit per month and 29.4% of operations with 10 or more visits per month. Additionally the use of vaccines is an important part of any biosecurity plan because complete isolation is rarely achieved. Approximately 68.9% of operations gave some vaccines to beef cattle or calves, but herds with less than 49 animals were less likely (59.4% to use vaccines than were herds larger than 50 head (86% or greater. Additionally operations in central US were more likely to vaccinate (90.7% than were operations in the west (76.3% or southeast (59.8%. To effectively prepare a biosecurity/biocontainment plan a thorough understanding of herd management including: value of animals, presence of disease in the farm or surrounding area, type of animals purchased, origin of cattle purchases, contact with neighboring herds or at shows, facilities available, feed

5 and water sources, amount and type of ranch traffic and many others. These determinations can only be found with proper records and identification of animals. Records According to NAHMS 2007, approximately 83% of operations kept some form of records with 90% of operations larger than 100 cows keeping some form of records. Approximately 66.1% of operations used some form of identification on some cows and 79.1% of cows had some form of identification with plastic ear tag being the most commonly used method on most operations (50.4%. Having the record an actually doing something with those numbers are where many veterinarians and producers fall short. Farms should strive for 63 day calving season for cows and a 42 to 45 day calving season for heifers which begins about 2 weeks before cow calving season. Benchmarks for Cow-Calf Operations Reproduction Goal Monitor Action Calf Crop % > <85 60 day Preg Rate > <90 1st 20 day Preg Rate > <50 Herd Average Cow Age 5 to 6 <4 or >7 Adult Dystocia (% <5% 6 to 7 >8 Heifer Dystocia (% <15 20 to 25 >25 Losses During Pregnancy (% <2 2 to 3 >3 Perinatal Loses (% <5 5 to 9 >10 Annual cow losses (% <2 3 to 4 >5 Culling rate (% 15 to 20 <10 or >25 Spire, 1990 AABP One of the single best records to keep is the calf crop percent or weaning percent. This is determined by ((number of calves weaned/number of exposed females * 100. This is an excellent indicator of reproduction, nutrition, and calf losses within the herd. However it does not account for excess use of feed and nonfeed inputs. Another important monitor is the calving distribution in 21 day increments during the season. Benchmarks from Cow Herd Appraisal Software from 74,000 + cattle SPA CSF Pregnancy % ADG 2.54 Preg Loss % 0.68 WDA 3.01 Calving % 92.9 Birth Wt 86 Calf Death Loss 2.9 Adj 205 Day Wt 639 Weaning % Frame Score 5.8 Replacement Rate % Heifers Early 36.4 CD Loss Based on # Born 3.14 % Heifers at

6 Average Age at Weaning 189 % Heifers at Calves at 21 Days 63.9 % Cows at Calves at 42 Days 88.9 % Cows at Calves at 63 Days 95.6 Cow Age 5.7 Calves After 63 Days 4.39 Cow Wt 1402 Steers WWT 575 Cow Condition 5.6 Heifers WWT 544 Bulls WWT 620 Average WWt 565 Lbs Weaned/Cow 505 Exposed *Downloaded May 27, Calving Management In the NAHMS 2007 survey, the percentage of heifers that required no assistance during calving increased from 1997 to 2007 (83.2 to 88.4%, respectively. However, the percentage of cows that received no assistance decreased slightly from 1997 to 2007 (97.3 to 95.7%, respectively. Important criteria that veterinarians should be involved with during calving: include management of the calving area prior and during calving, preparation for managing passive transfer in calves either through colostrum harvested on the farm or high quality colostrum replacers, and identifying the appropriate calving season. Identifying the appropriate calving season with regard to nutritional management and marketing opportunities may be the most important decision a farm makes during the year. Weaning Management Weaning is one of the most stressful times in a calf s life. The stress is believed to be the result of a combination of the severance of mother-young bond (Weary, 2008 and the loss of milk supply (Ungerfeld, In one study conducted by Haley in JAS 2005, calves weaned with the use of a quiet wean nose flap vocalized 96.6% less, spent 78.9% less walking and 23% more time eating after separation from the cow than did the control calves. However, average daily gain did not differ. Another alternative to abrupt weaning is the use of fence line weaning techniques. However, a recent study from Brazil questioned whether fence line or use of nose flaps actually decreased weaning stress or actually redistributes the stress to different time periods during and following weaning (Enriquez, DH, et al Unfortunately, this is an area where full understanding is not complete, but it should be an area discussed with farm to determine what method is most beneficial for the animal and the farm. Animal Welfare As stated in the veterinarian s oath Being admitted to the profession of veterinary medicine, I solemnly swear to use my scientific knowledge and skills for the benefit of society through the protection of animal health, the relief of animal suffering, the conservation of livestock resources, the promotion of public

7 health and the advancement of medical knowledge.., we have an obligation to care for animals and minimize suffering they may face. Historically, most stockmanship practices on a farm were learned by watching or being trained by other generations. However many workers on farm no longer come from a farm background, so this skill set is lacking. These employees and sometimes farm owners are forced to figure out things on their own to get the job done. Veterinarians play an important role in helping train future generations of cattle owners how best to handle animals. These trainings can be topics such as: low stress animal handling, use of genetic selection for docility, improved facility design, methods of euthanasia, and which euthanasia method is best for the farm. Additional discussions that veterinarians should have with owners include how best to handle down animals. Is there a tarp or sled on the farm that will prevent the cow from being dragged? Can front-end loader be used? At one point should this animal be euthanized? References available on request