Cow-calf sick pen management
Keeping enteric diseases at bay means using good sanitation and disinfection to control pathogen exposure in areas where sick or injured animals are housed and/or treated on the farm. Efforts should be focused on the calving pens, facilities where dystocias are handled and housed, sick cow and calf treatment areas, and on treatment equipment.
Dystocia management pens in the calving barn must be managed to minimize pathogen build up and infection pressure on calves, says Mike Sanderson, DVM, Dipl. ACVPM, Dipl. ACT, Kansas State University. "They should be easily cleaned and support minimal pathogen loads. Concrete floors are easily cleaned and disinfected, but compacted sand or gravel may be a more economical alternative. Sand and gravel have low organic content, support minimal bacterial growth, and can be scraped and replaced between calving seasons."
These pens should be bedded and bedding removed between calvings to remove contamination. Judicious use of lime may be helpful in decreasing pathogen survival, and ideally a period of time for drying should be allowed after cleaning and before being used again.
Pens where sick cattle are managed should be separate from the calving pen and where dystocia cases are managed. "Cleaning and disinfection of morbidity areas is very important, as these animals are shedding pathogens at high levels," Sanderson explains. Human, pet, wildlife and insect travel from the hospital area should be avoided. "Because of the potentially high level of shedding from sick cattle, even small amounts of feces may contain an infectious dose, including amounts on fly feet and mouth parts. Pets and wildlife should be excluded from the hospital area, and human traffic from the hospital area to the dystocia management pens or nursery areas should be prohibited without thorough disinfection."
If possible, care and duties should be arranged so that sick cattle are attended to last. At minimum, easily disinfected rubber boots should be worn and scrubbed clean of all organic debris, followed by disinfection and a change of coveralls before moving from the morbid to healthy calves.
Equipment used for treating sick cattle should be used exclusively for the hospital area and not transferred for use on healthy cattle. Between uses in the hospital, equipment should be thoroughly washed and disinfected. Equipment should not be stored in disinfectant, as once it is contaminated with organic matter, it can serve as a source for contamination of equipment.
Performance of disinfectants is affected by numerous factors including temperature, pH and water hardness. No available disinfectants work well in the presence of organic matter such as blood, feces, milk and even dirt. As such, thorough cleaning of surfaces is necessary before application of disinfectants. Further, once the mixed disinfectant becomes contaminated with organic debris, it should be discarded.
The type of surface to be disinfected also influences effectiveness. Wood surfaces are porous and the nutrients from the wood can support some bacterial survival. Painted or varnished wood is easier to clean and retains less pathogen load, and plastic surfaces are easiest to remove pathogen load from. High pressure spraying should be used with caution as it may aerosolize pathogen load and disperse it.
This information was presented at the 2007 Western Veterinary Conference.
Communicating with the media
These tips on communicating with the media are offered by the Washington State Veterinary Medical Association.
When media call, ask, "What can I help you with today?"
Remember your rights. You can ask the reporter for information which will help you prepare for the interview. What type of story is being written? What"s the angle and are others being interviewed? What is the reporter"s deadline? Know or find out the audience, i.e. daily newspaper vs. TV news.
Try to buy time to collect your thoughts, i.e., "Can I call you back in 30 minutes, I"m in a meeting now?" Prepare three to five key messages you want to communicate to your audience. Plan your points and make them early. Remember an interview is an opportunity to tell your story to your audience, not the media. Use every question as an opportunity to address your agenda.
Be brief, professional and calm. News is presented in small "bites" of information both for radio and television. Keep your messages down to a few lines and make sure to make your point often.
Anticipate and rehearse possible interview questions and answers. What are your vulnerabilities?
Use common language and examples. Every industry has its own jargon which some reporters may understand, but the general public may not. Be careful to explain abbreviations and avoid jargon.
Tell the truth. Don"t like or speculate. Beware of hypothetical statements. If a reporter asks, "Would you say…" and then quotes a statement for y our agreement or disagreement, don"t accept it. Don"t let anyone determine your agenda. Make your own statement. Also, don"t repeat the reporter"s negative statements.
Admit when you don"t know an answer and offer to find it. Then do it.
Never speak "off the record."
Never say "No comment." If you can"t comment, say you can"t and explain why. "I"m sorry but our attorneys have asked us not to discuss that aspect." Certainly you and your readers/viewers realize this is an ongoing criminal investigation so I can"t say anything that might jeopardize that."
Help the reporter do their job. Consider this a business relationship not unlike talking to any other vendor or service provider you deal with daily.
Be accessible, cooperative and non-confrontational.
Refute any untrue statements immediately and politely. Make sure to correct it in an informative and helpful manner.
Use data sparingly to underscore your most important points.=
NPN may help after drought
Effects of the 2006 drought, such as reduced forage production and lower feed quality, may still linger for producers on the farm over the next few years.
During a drought, plants utilize previously stored carbohydrates in the roots and crown. This drain on carbohydrates can result in the loss of root vigor and fewer basal buds to develop for next year"s growth. In turn, this can lead to a reduction of forage and drought-stricken plants that contain less protein, energy, vitamin A and phosphorus in the year of drought, as well as in subsequent years.
To combat the poor feed utilization caused by drought, some producers are turning to non-protein nitrogen (NPN) to help increase their herds" source of soluble protein.
"There are times when the forages and grains do not contain enough rapidly soluble protein or NPN, so the bugs get starved for NPN and cannot perform their function of digesting feed and building microbial protein, says Charlie Elrod, PhD, dairy consultant Newfield, N.Y. "So feeding a little urea or NPN can help overcome that slump and meet nutritional requirements of the rumen bugs, which allows them to continue digesting fiber and carbohydrates."
According to Elrod, two populations of rumen microbes exist: starch digesters and fiber digesters. The starch-digesting bugs get their energy from starches, sugars and pectins while they get protein from both amino acids and ammonia. Fiber digesters, however, use cellulose and hemicellulose from forages as their energy supply and ammonia as their source of nitrogen to build microbial protein.
Nutritionists have often struggled to meet the needs of the fiber digesters," says Elrod. "We can get the fiber to them, but not always the consistent supply of ammonia that they need."
Elrod states the dairy industry now recognizes that fiber bugs need about 10 milligrams per 100 milliliters as the minimum concentration of ammonia in the rumen to stay fully active. When the concentration falls below that, the fiber digesters are just coasting.
"It"s like a carburetor that has all the air it needs, but no gas to mix with it to fuel combustion," Elrod says. Non-protein nitrogen products can help overcome the coasting digesters by providing a controlled-release urea into the rumen.
"Urea is so rapidly available in the rumen that it"s gone within 15 to 45 minutes," Elrod says. "With NPN, you can actually pull some other protein source such as soybean meal or corn gluten meal out of the diet. Nutritionists have also found that they can lower the total crude protein of the diet since the increased microbial protein is more highly digestible."
This Practice Tip provided by Alltech.
Improve feedlot performance
Veterinarians can use nutrition, vaccination and metaphylaxis strategies to prevent or decrease the impact of feedlot respiratory disease. "Accurate identification of sick cattle in feedlot settings is challenging, but new technologies may become available to improve diagnostic accuracy," says Bob Larson, DVM, PhD, Kansas State University.
A number of factors combine to initiate most cases of bovine respiratory disease (BRD): stress (shipment, social interaction and nutritional), viral infection and bacterial infection. Recently weaned calves and light stocker calves have higher morbidity and mortality rates than yearling cattle.
BRD is the primary cause of sickness and death in feedlot operations. Edwards (1996) reports that 65–80% of morbidity within a feeding period occurs in the first 45 days, and 67–82% of the total morbidity was due to respiratory disease. Mortality rates ranged from 0.57–1.07% of all cattle received, with respiratory disease accounting for 46–67% of deaths. Another study reported that calves treated for BRD early in the feeding period gained 0.14 lbs. less per day during the entire feeding period compared to healthy penmates.
There is evidence that disease has the potential to affect not only carcass weight, but also the amount, location, and ratio of muscle, fat, and water.
Some indicate that cattle treated more than once for BRD had more pronounced negative growth and carcass effects than cattle treated only once.
At arrival, calves should be placed in dry lots with free access to good-quality grass hay and fresh water and allowed to rest overnight. A minimum of 22–26 in. of bunk space per animal should be provided. The bunks should be kept clean and old feed removed daily. Upon arrival, 1–2 lbs. per head of a palatable protein pellet should be offered. Clean water tanks with water running from a hydrant will often encourage calves to drink, as many are not accustomed to automatic waterers.
In stressed calves, feed intake is low the first week, increases through the third week and plateaus during the fourth week. It is essential that a palatable ration is offered, and nutrient densities are raised when intake is low. Pounds of nutrients consumed during the receiving period are of greater importance than are percentages of nutrients in rations.
Silage should not be included in receiving rations during the first two weeks, as it is associated with illness and mortality. Silage is generally low in protein. Once it is included in the diet, calves should be supplemented with natural protein. Alfalfa hay often causes bloat and contributes to loose stools. Moldy or poor-quality hay decreases consumption and should be avoided.
Concentrate levels above 55% during the receiving period can contribute to higher levels of illness, but average daily gain and feed efficiency improves. Good-quality, long-stem prairie or oat hay results in the lowest illness and mortality rates. A good balance of health, average daily gain and feed efficiency is obtained when a ration approximating 72% concentrate is fed. Feeding long-stem grass hay free-choice, with up to 2 lbs./day of a palatable 38-40% natural protein pellet results in excellent health performance, and gains of 1-2 lbs./day can be expected during a 28-day receiving period. Calves perform better if a completely mixed diet is fed.
Crude protein (CP) content in the starter diet should also be relatively high. The starter or weaning ration should contain at least 14% CP on a dry matter basis. Increasing the CP concentration of receiving diets can increase average daily gain the first 14 days in the feedlot.
Activities such as dehorning or castration may be delayed in high-risk cattle until the risk of respiratory and other disease decreases. Deworming and vaccination against viral diseases should be done within 24–36 hours. Each day that processing is delayed results in a 1% increase in rate of illness. It is important to process in small groups, so no animal is out of its pen for more than 30 minutes.
Process early in the morning to avoid higher environmental temperatures later in the day and to avoid artificially elevated body temperatures taken in the afternoon. Calves with a high body temperature (i.e., 104' F or greater) or showing other signs of illness should be separated from the group and treated, if an infectious disease that will respond to antimicrobials is deemed likely. The appearance and history of the calves should be considered in deciding whether the calf is actually ill.
Many calves entering feeding operations are highly stressed and may only be able to respond to a limited number of antigens. The veterinarian must consider risk of disease, stress level of the calves, age of calves, stress induced by vaccination, efficacy of the vaccine, previous vaccination history, and the time of onset of disease after arrival.
The benefit of vaccination upon arrival is uncertain in some cases. It has been demonstrated that modified-live viral vaccines will likely provide protective immunity within days.
Finding sick cattle
If BRD cases are identified early, antibiotic treatment is likely to succeed. Late detection of BRD cases increases the number of re-pulls, chronics, railers and deads. Sick cattle may have the appearance of lack of rumen fill, nasal discharge, or increased respiratory rate and/or difficulty, and may act differently from healthy pen mates with a decreased interest in their surroundings, lowered head and ears, and reluctance to move or moving without "purpose." Cattle need to be observed while standing quietly, as well as moving.
Limitations of diagnostic strategies
Traditional BRD-detection methods are relatively inaccurate. Cattle instinctively hide overt signs of illness. Cattle in many feedlot settings may only be examined for a short period of time one to three times per day. And determining an individual animal"s true health status based on a brief observation within a large population is challenging.
An evaluation of the accuracy of current diagnostic methods can be performed by comparing animals that were treated for clinical illness to the total number of animals with lung damage at harvest. Studies have shown that large numbers of animals that were not pulled for treatment did have lung lesions at harvest.
Quantitative measures to accurately identify sick cattle would enable prompt treatment and minimize disease impact. The possibility of using GPS or pedometer technology to track animal movements within a pen of cattle to identify individuals that move significantly less than the majority of pen mates is potentially a method to provide a timely and objective indication of individual animal illness.
Some producers utilize mass medication at arrival or a few days later with injectable, long-acting antibiotics or feed-grade antibiotics for high-risk cattle, in an effort to reduce the number and severity of sick animals. This can be cost-effective in some situations. When there is a shortage of labor or when the percentage of sick cattle is high, mass medication may be useful. It is of greatest benefit when used on high-risk exposed cattle assembled from several sources or on extremely stressed calves.
Treating calves with respiratory disease
Once identified as needing respiratory disease treatment, cattle are treated with at least a three-day protocol of antibiotics. Antibiotics should reach effective concentrations in diseased lungs and be effective against the bacterial organism causing pneumonia. The determination of which product to use is based on how the antibiotic distributes itself in the calf"s body, laboratory determination of susceptibility of the bacterial organisms to the antibiotic and previous clinical response on that particular farm. Therapy cost along with treatment effectiveness should be considered. Case fatality rate and proportion of re-treatment are important BRD treatment variables when determining dollars available to move to an alternate BRD treatment. In addition, sale price and cost of gain are important for selecting the BRD treatment.
This information was presented at the 2007 Western Veterinary Conference.