Foundations of Efficiency: Growth and Economics

The key revenue producing aspects in cow-calf beed operations are: live born calf ratio, breed-back efficiency, and genetic quality.

• Any animal that is going to be sold has to be alive. The animals being raised need to have maternal traits that not only help with the calving process (i.e. calving ease, milk production, etc.), but will also have to possess maternal traits essential to keeping the calves alive. These include: having the “motivation” to get the calf out, claiming the calf, and not wanting to kill the calf after it is born in order to “protect” it. These maternal traits are hereditary and a producer can benefit greatly from being strict in culling for key maternal traits and disposition.
• Breed-back capabilities can range from many different aspects and are a key component that the producer needs to maintain. One determinant is nutrition. Skinny and fat cows don’t breed. Cows with a BCS of less than 5 can take longer to reach estrus and cows with a BCS above 5 can fail to cycle all together. A producer’s job is to condition cows by supplementing or restricting dry matter intake in order to proficiently breed each cow so that she has a calf every year. There are occasions where this is out of the producer’s hands, such as a pathological issue in which breeding could be difficult or even impossible. Such diseases as BVD, Brucellosis, Trichomoniasis, or even Leptospirosis can cause abortion or poor implantation in the cattle affected. Therefore it is important to keep up with the general health of the animals.
• The final key to revenue in beef cow-calf operations is genetic merit. How hard the calves can push down the scales (weight) can essentially determine how much a producer is going to receive monetarily. However, the producer needs to balance different genetic material as there can be problems if the calves are be TOO big. Cesarian sections are a revenue depleting option if the cow cannot calf naturally. Producers need to look for solutions in genetics depending on their strategy of when to sell their calves. If they are strictly looking to sell calves at weaning, then they should look for calving ease bulls to breed to heavy milking cows to get the calves to weaning quicker, all the while being more efficient on feed conversion. However, heavy milking cows utilize a lot of energy to supply energy to their calves. A producers has to look at what system works best for him/her and weigh in feed costs, facility expense, and time all as important factors. There are a few key physiological factors that every producer needs to keep in mind in a cow-calf operation.

The Key physiological principles of a beef cattle operation

1. Reproduction: timing and methods are the backbone of a cow-calf beef operation and is often completed via artificial insemination (AI).The timing of AI is important, making sure the cow or heifer is receptive so that semen is not wasted (as well as the reproductive potential if the conception window is missed). The best way to do this is to monitor the timing of estrus, which is done primarily by visual monitoring (cite Smith et. al). If everything is done properly with regards to timing, then the cow should calve and be receptive again before the next breeding season.
2. Immune System: the calf will get the majority of its initial immunity from the colostrum of it’s mother, therefore making sure she has an appropriate number of immunoglobulin (IgG) antibodies is important for the survival of the calf and the economics of the operation. It is important to make sure the mother is properly vaccinated to ensure the immune capacities of the calf. The timeline of vaccinating the mother is also important, and it was found that vaccinating four weeks prior to calving is the ideal time frame with regards to total colostrum IgG load (cite MSU).
3. Nutrition: for an ideal pregnancy, proper nutrition needs to be started at least 1 month before conception (possibly cite). If a cow has poor nutrition the month prior to insemination, the birth weight and performance of the calf is likely to be detrimentally affected, regardless of nutritional management during pregnancy (need to cite, Dr. Lowe and Aldridge spoke of this). Cattle with lower body condition scores (BCS) had longer postpartum intervals than those with higher BCS scores, and this could become a problem if it means that the lower BCS cows don’t come into estrus during the breeding season (Freetly et. al).

Many producers have realized that genetics are a major factor in running an efficient production system. Through the use of reproductive technologies, desired genetics have become more vastly available. The better focus on genetic management leads to highly productive animals and systems.

Producers use statistics of different physiologic situations, based off of genetics, in order to streamline efficiency and increase profit for the cow to calf operation. For example, the calving ease direct (CED) is expressed as a difference in percentage of unassisted births. This can be useful in making decisions about what bulls to use on first calf heifers, which are typically just reaching maturity and have a smaller frame size and no experience calving. This can help to keep input costs low and efficiency high, due to less distocias. When a cow undergoes problems during calving there are several situations that could arise: lower conception rates, longer rebreeding time, higher input costs, and a loss of efficiency at the cost of the producer.

Another example is weaning weight (WW) which is the probability that the weaning weight will be transmitted to the offspring. Weaning weight is taken at 205 days of age. A higher WW would be very beneficial in a cow-calf operation due to the likelihood of the calves being sold shortly after weaning. A higher weaning weight increases the income that a producer will have.

The following is an example chart used to help predict genetic differences in beef cattle. It is called an Expected Progeny Differences chart. The chart includes numbers of about ease of calving (CED), prediction of birth weight (BW), accuracy of BW prediction, weaning weight (WW), yearling weight (YW), residual average daily weight gain (RADG), yearling height (YH), scrotum circumference (SC), docility (DOC), heifer pregnancy (HP), and calving ease of the sired heifer (CEM). Producers use data, such as that below, to help decide which genetics are important to their operation to help keep production at its height.

Along with a producer staying efficient with the keeping track of genetic factors, a producer needs to focus on the nutritionally needs for the whole production system in order to maintain production and input cost efficiency.

A healthy and well-balanced diet is very important in a cow-calf operation in order to successfully reach the cows highest weight potential.

• Colostrum contains many vital nutrients, vitamins, and immune cells to help the calf within its first few months after birth. The calf at birth does not have its own immune system working properly yet. The antibodies that it receives from its mother help to combat any sickness or disease exposures that may occur at the beginning of its life.

Cows that have matured should have different nutrition depending on their stage of life. Before calving, the cow should be fed a high quality forage diet. This will help maintain the cows current weight, return to heat cycles quicker, and produce enough milk for the calf to have sufficient nutrition to reach a better weaning weight. After calves have been weaned, the cows can be fed a lower quality forage diet for a couple months. A very important important part of a cow’s diet are minerals. A variety of minerals can be supplemented such as Salt, calcium, phosphorus, copper, zinc, and magnesium. Mineral deficiencies in a cow can lead to many metabolic issues such as reduced weight, reduced body condition scoring, milk production, and health related problems.

Pasture grazing is a very important part of the diet of a cow-calf operation and should be the majority of the forage that the cow intakes. There are various ways to address pasture grazing. Feed costs can be reduced for the herd by grazing fields after harvesting. Cows can graze on the annual grasses that grow during the summer and warm months of the year. During the winter and colder weather, the cows can be fed on stored feed (such as hay or silage). Beef production efficiency can be increased by properly rotating the calfs and cows between pastures/land. One method of pasture grazing is called intensively managed grazing.The picture depicted below shows an example of ‘resting’ (green) and ‘grazed’ (yellow). The x-axis represents the number of times they are rotated or switched. So 10 times for one year. The Y-axis represents the number of pastures (which is not labeled but has 6 present). The size and and number of pastures is dependent upon the economically and ecologically efficiency, which can vary from different livestock environments.

It is vitally important that cows are fed proper nutrition in order to maintain weight and be able to breed effectively in a cow-calf beef operation. Some of the major nutritional issue begin when the cows need to come off forage (such as during the winter) due to lack of sufficient roughage, and need to be put on concentrate diets.

Below are some common nutritional diseases that every beef farmer should be aware of and help prevent:

• Grass Tetany can be a problem during the early spring months when forage has low magnesium. It may be important to spray magnesium supplements onto the pasture to make sure that lactating cows get the correct magnesium balance needed. However, the most effective way is to supplement their diets directly. If not prevented, or treated within 12-24 hours, a down cow may die due to grass tetany.
• Bloat is another important dietary factor that a client needs to be aware of. It’s important that hungry cattle are not put out on lush legume or small grain pastures without first eating hay. Bloat can manifest acutely and cause death within an hour. Poloxalene salt blocks can be used to help prevent the foam from building in the rumen and causing bloat.
• Metabolic Acidosis is always an issue for ruminants, but especially calves. Calves with underdeveloped rumens should not be put on a high concentrate diet as it may cause acidosis. If the client needs to transition to concentrates, they should be slowly put onto a concentrate diet and at least have 10% roughage along with the final diet.
• White Muscle Disease can be an issue if cows are fed a low selenium diet while pregnant. It is important to supplement selenium and Vitamin E to cows at least 4 weeks before calving. If this is not prevented, the calves may die from acute cardiac disease or a slower muscular weakness disease caused by decreased vitamin E levels at birth.

Overall, it is important that the clients keep up with the pasture nutrition of their animals. Something as small as keeping debris away from the pasture may prevent something like Hardware Disease which can cause infections that lead to costly surgery or death. Also, producers need to ensure that there is no poisonous roughage in the pastures that may hurt the health of their animals.

When considering any animal, especially cattle within a cow-calf operation, there are many influencing factors which include pathogen exposure, stress, environmental conditions, genetic composure, temperament of the animal, and nutrient availability. The immune system is constantly functioning to maintain homeostasis within the body, which is important to owners of cow-calf operations in order to maintain production.

While all these factors and more interfere with immune potency the major factors to focus on when managing a cow-calf operation would be nutrition, stress, and pathogen exposure.

Nutrition

Stress

The magnitude of stress can both inhibit health and productivity of the animal. When conducting this operation, on the management side, it is key to provide adequate environment that will provide the least amount of stress exposure to the population of cattle. Depending on the managerial approach, development of the cattle can be done in a relatively low stress environment. Under the influence of high levels of stress cattle can become immune suppressed, thus giving a way to opportunistic diseases.

Pathogens

The mucosal immune system is referred to as the first line of defense or a barrier against most potential pathogens. Cow-calf operations typically are conducted where there are large social interactions between cattle. This animal-to-animal contact does increase the chances of pathogens to spread. On the other hand, these cattle are normally restricted to interactions within the same herd, so in theory since birth they will all be exposed with immunity to the same pathogens in their surrounding environment. Vaccinations and antibiotics are options in order to assist with immune responses to specific pathogens that do occur within a herd.

3 major infectious diseases

Anaplasma can be transmitted through two routes, mechanical transmission when infected red blood cells are inoculated into susceptible cattle, or can be transmitted through its biological vector. Mechanical transmission can occur during many processes that frequently occur in cow-calf production. Some of these include dehorning, needles, ear taggers, castrating knives, surgical instruments, and it can also occur through the mouthparts of biting insects. Biological transmission requires the biological vector which in the case of anaplasmosis is the wood tick. This can present a problem as the parasite can proliferate inside of the vector and infect susceptible animals. Once infected this parasite proliferates throughout the blood, and attaches to the red blood cells. The cattle’s immune system destroys the red blood cell in attempt to fight the infection, however uninfected blood cells are also destroyed.

This disease plays a large role in efficiency due to treatment costs, preventative measures, testing, and problems within undiagnosed herds. Preventative measures can be costly to producers as it requires insect and tick control, as well as thorough cleaning of instruments and switching needles between every animal, adding both time and cost into processing animals. This time typically involves an animal in the chute potentially getting stressed, allowing for a susceptible animal.

https://pubs.ext.vt.edu/400/400-465/400-465.html http://icwdm.org/PDF's/anaplasmosisTXA&M.pdf

3 major antimicrobials

Choice of antibiotic is a very important decision that the veterinarian and farmer must agree upon together. Differing withdrawal periods will dictate which is used based off of the purpose of the animal. For example, if it is going to slaughter, then choosing the appropriate antimicrobial with a shorter withdrawal period would be ideal.

Oxytetracycline is a broad spectrum, injectable antimicrobial that belongs to the Tetracycline family. Diseases that it is effective against include but is not limited to: pneumonia, shipping fever, foot-rot, bacterial enteritis, and leptospirosis (see FDA for specific pathogens associated with these diseases). According to the FDA, it has a withdrawal period of 19 days.

Ampicillin is a broad spectrum antibiotic that belongs to the penicillin family, and is derived from penicillin. It acts by disrupting the formation of bacterial cell walls, leading to their lysis (NIH). Ampicillin is commonly used to treat respiratory infections in cattle and is also safe in un-weaned calves (FDA). This drug’s withdrawal period is 6 days.

Erythromycin is an injectable medication listed in the class of Macrolide antibiotics, and it commonly used in the treatment of bovine respiratory disease. This drug acts as a bacteriostatic and prevents the production of certain peptides (NIH). Erythromycin’s withdrawal period is stated to be 6 days (FDA).

These vary between herds and can protect against many different diseases such as pinkeye, leptospirosis, blackleg, etc. However, these programs are completely voluntary to the producer. Some auction centers promote this and offer special sales in attempt to generate more revenue. Some producers do not implement these practices and rather choose to “play the odds” and try to avoid these illnesses and save extra money and time. A sample vaccination program for calves is listed below from the University of Illinois.

For cows and bulls (heifers) four to six weeks before breeding it is common to vaccinate with viral respiratory vaccine with Campylobacter fetus and 5-way Leptospirosis- Fetal Protection, and 7 way Clostridial (Blackleg), with a deworming done in spring and summer. Calves between one and three months of age should be vaccinated with 7 way Clostridial which initiate immune process, viral respiratory vaccine, and dewormed. Calves from two to three weeks pre-weaning typically receive the viral respiratory vaccine, 7 way Clostridial vaccine, and dewormed. Weaning calves traditionally receive booster viral respiratory vaccine, scours vaccine, and booster of 7 way Clostridial (if label directs). Parasite control for cow calf operations is vital when considering the contact the cattle have with the environment.

1. Producers can find cattle bringing in new diseases when they purchase replacement females and sires such as Bovine Viral Diarrhea and Trichomoniasis. Such diseases can spread throughout the herd and cause decreased reproductive merit and efficiency. Testing can be done from ear notches and reproductive tract swabs to identify potential threats to the herd.
2. Basic hygienic procedures such as washing boots, hands, clothes, etc. all can decrease the potential to infection. Utilizing vehicles that have previously been on an infected farm can also be a vector. These seem like common sense, but many producers are careless about these procedures until something impacts their herd and it’s too late.
3. If these animals are being housed in structures, infection can be spread if a disease is “living” in the walls, bedding, etc. Another part of the environment that can incorporate disease can be wildlife adjacent to the enclosure. Physically, the structures need to be sound in order to avoid open wounds, tetanus, “hardware disease” etc. Though these are not contagious between animals, they are a threat to the health of these animals.
4. Early detection of illness via BCS scores. It is important for the beef producers to monitor their entire herd. If animals fall below a 5 out of 9 body condition score there is a much larger chance the animal is going through a disease process.

Veterinarians need to educate farmers and their employees on how to properly handle themselves around sick animals with regards to personal protective equipment, eliminating unnecessary human contact, and by maintaining the following:

1. General Herd Health: maintaining a vaccination protocol and establishing rules for new animals entering the herd.
2. Human/animal hygiene: for example the pathogen Cryptosporidium Parvum which is spread primarily from calves to humans via fecal-oral transmission, can cause zoonotic disease. If a stall that housed an infected calf is cleaned improperly (e.g. with pressure washer), then fecal material can become aerosolized and ingested by the cleaner and/or other animals, perpetuating the problem.
3. Control of population size: if one animal does get sick, the disease will spread much faster if the animals are frequently in close contact to one another. If multiple animals are infected by a zoonotic disease, then there is a greater chance for zoonotic transmission to humans.
4. Stress control: animals that are stressed have a weakened immune system and are more susceptible to disease

FOREIGN DISEASES (FAD)

BSE is classified as a neurological disorder where prions are present and “infecting” the animal. Similar to Chronic Wasting Disease in deer, these animals are hypersensitive to many stimuli, uncoordinated, etc. This disease has two different variants classified as classical BSE and atypical BSE. Human consumption of BSE infected cattle can correlate to that person contracting Creutzfeldt-Jakob disease. Classical BSE is seen when cattle are fed rendered products of infected animals, i.e. meat and blood meal from other infected cattle. Since the United States Department of Agriculture prohibited this practice since 2009, classical BSE SHOULD only be seen in the United States in animals that could have been imported from another country that has not done so. The other variant of BSE is called atypical BSE. In this case, the disease seems to occur spontaneously and is relatively uncommon. The USDA ranks countries by their risk of exported animals to have BSE, where atypical BSE does not affect this value as it is unpredictable. Any animal found to be positive for BSE does not enter the food chain. Any animal presented as down upon arrival at the slaughterhouse cannot enter the food chain

There is always a “scare” about what new disease is going to occur next and it is important to identify potential diseases before they can spread to the human population.

REFERENCES

https://www.researchgate.net/profile/Calvin_Ferrell/publication/12264237_Timing_of_realimentation_of_mature_cows_that_were_feed-restricted_during_pregnancy_influences_calf_birth_weights_and_growth_rates/links/00b49533e9816d85db000000.pdf

https://msu.edu/~mdr/vol15no2/cowandcalf.html

http://beefrepro.unl.edu/proceedings/2011northwest/02_nw_synchprincipals_dalton.pdf

http://drought.unl.edu/ranchplan/BeforeDrought/GrazingStrategy/RotationGrazing.aspx

http://www.beefmagazine.com/americancowman/beef-and-business/0407-trace-minerals-supplement

http://www.cattlenetwork.com/bovine-vet/bv-magazine/immunology-of-the-neonatal--calf-113985689.html

https://pubs.ext.vt.edu/400/400-012/400-012.html

https://www.uaex.edu/publications/PDF/FSA-3071.pdf

http://extension.psu.edu/animals/beef/nutrition/articles/diseases-of-grazing-beef-cattle

http://arrowquip.com/blog/cattle-diseases-signs-and-prevention/

http://edis.ifas.ufl.edu/an292

https://www.adsa.org/archive/discover/23rdDiscover/Discover23Int_Summ.pdf

http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1193&context=extensionhist

http://extension.usu.edu/files/publications/factsheet/AH_Beef_27.pdf

https://pubs.ext.vt.edu/400/400-465/400-465.html

http://icwdm.org/PDF's/anaplasmosisTXA&M.pdf

• Virginia Cooperative Extension. (2009, May 14). Injectable antibiotics approved for use in beef cattle. Retrieved March 01, 2017, from https://pubs.ext.vt.edu/400/400-008/Table_1.html

• Ampicillin | C16H19N3O4S - PubChem. (2005, June). Retrieved March 01, 2017, from https://pubchem.ncbi.nlm.nih.gov/compound/ampicillin#section=Top

• Oxytetracycline | C22H24N2O9 - PubChem. (2011, December). Retrieved March 01, 2017, from https://pubchem.ncbi.nlm.nih.gov/compound/oxytetracycline#section=Top

• Erythromycin | C37H67NO13 - PubChem. (2005, June). Retrieved March 01, 2017, from https://pubchem.ncbi.nlm.nih.gov/compound/12560#section=Top

• FDA. (n.d.). FOIA Drug Summaries - NADA 140-582 Oxytetracycline Hydrochloride Injection, 50 mg and 100 mg. Retrieved March 01, 2017, from https://www.fda.gov/AnimalVeterinary/Products/ApprovedAnimalDrugProducts/FOIADrugSummaries/ucm049902.htm

• FDA. (n.d.). FOIA Drug Summaries - ANADA 200-180 Ampicillin Trihydrate - original approval. Retrieved March 01, 2017, from https://www.fda.gov/animalveterinary/products/approvedanimaldrugproducts/foiadrugsummaries/ucm118361.htm

FDA. (n.d.). FOIA Drug Summaries - NADA 012-123 GALLIMYCIN (Erythromycin) INJECTION, 200 mg/mL - supplemental approval (June 30, 1993). Retrieved March 01, 2017, from https://www.fda.gov/animalveterinary/products/approvedanimaldrugproducts/foiadrugsummaries/ucm063685.htm

https://www.natureword.com/tag/importance-of-colostrum-in-immunity/

http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/faq8021

http://www.beefmagazine.com/prevention-works/protecting-your-cow-herd-disease

http://www.cattlenetwork.com/cattle-news/Biosecurity-for-cow-calf-operations-200116901.html

http://www.cattlenetwork.com/cattle-news/Herd-health-Vaccinations-for-the-cow-calf-operation-198785571.html

http://extension.psu.edu/business/ag-alternatives/livestock/beef-and-dairy-cattle/beef-cow-calf-production

• USDA. (2009, December). Biosecurity on U.S. Beef Cow-calf Operations. Retrieved February 25, 2017, from https://www.aphis.usda.gov/animal_health/nahms/beefcowcalf/downloads/beef0708/Beef0708_is_Biosecurity.pdf

• Cornell University. (n.d.). Potential Zoonoses Associated with Cattle. Retrieved February 25, 2017, from https://ras.research.cornell.edu/care/documents/OHS/zoonosis_information_sheet_cattle.pdf

Picture retrieved from https://www.google.com/search?q=cleaning+cattle+stalls&biw=737&bih=871&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj615ma1bbSAhVkyoMKHcPjDs4Q_AUIBygC#tbm=isch&q=cleaning+cattle+stalls+pressure&*&imgdii=0Si0A9NPdgPBZM:&imgrc=uL1nssYflPSM5M:

http://www.tickencounter.org/tick_identification/rocky_mountain_wood_tick