| ||Section II, the Health Management unit of the Alberta Feedlot Management Guide is made up of thirty fact sheets providing information on every aspect of the health management of feedlot and backgrounding cattle. The fact sheets provide information necessary for the identification, prevention and treatment of common cattle diseases and parasites. Topics range from health management strategies in order to optimize production and minimize expense; descriptions of the many diseases that can affect cattle, with contributing organisms and control strategies; to practical suggestions for the control of parasites and insects.
Feedlot Health Management
An examination of the role played by the feedlot veterinarian as part of the health management team when implementing a feedlot health management program. Goals of the program are to optimize production and maximize profit through the reduction of death loss and drug expenditures. A successful program involves constant surveillance of the herds for disease in regular inspections by pen checkers trained in detecting signs of ill health; treatment protocols recommended by the veterinarian and subject to constant review; vaccination protocols and proper nutrition dictated in consultation between the veterinarian and a nutritionist.
Control and Prevention of Diseases of Feedlot Cattle
An analysis of the stressors contributing to disease in feedlot cattle with suggested procedures to follow in order to minimize their effect. The incidence of acute respiratory disease complex can be reduced in recently weaned calves by following certain protocols before introducing a calf into the general population of cattle from different backgrounds. Preconditioning and preimmunizing the calf can give it a greater chance of survival, but the feedlot manager must balance the greater costs of such calves with projected mortality losses from the purchase of lower priced, freshly weaned calves.
Investigation and Management of Epidemics of Disease in the Feedlot
A review of procedures to follow in the event of a disease outbreak in feedlot cattle. Primary objectives must be to investigate the cause and extent of the outbreak, as an analysis of the distribution of the disease will determine if it is due to an external cause such as a feeding accident, of if there is an epidemic of an acute infectious disease. Isolating the cause of the outbreak will dictate the management and treatment of affected animals.
Record Keeping and Analysis
An emphasis on the importance of maintaining animal health records as part of the production records of a feedlot. The animal health records can include group processing records (dates of any procedure or preventative treatment); individual treatment records which would include the treatment history of an animal; and death records. A case summary record for a specific animal in the feedlot can include the processing, treatment and death records of the animal, and along with production data can provide the feedlot with a record of its performance.
Processing Incoming Cattle
An emphasis on the importance of attention to detail and a prompt, effective processing program to give cattle a successful start in the feedlot. Early screening and treatment of high-risk calves upon arrival can greatly reduce the risk of Bovine Respiratory Disease losses. Other preventative procedures such as mass injections of long acting antibiotics, vaccinations and the use of performance enhancing implants have all contributed to the successful adaptation of calves to feedlot conditions.
Description and control measures for the disease “Pneumonic pasteurellosis” in feedlot cattle. The condition, caused by an interaction of bacterial and viral infections, environmental conditions and management practices has been a major cause of economic loss to the feedlot industry. Vaccination programs and preconditioning of calves before transport as well as management practices to reduce stress make an effective contribution towards controlling the disease.
Salmonellosis Feedlot Cattle
A description of Salmonellosis in feedlot cattle with symptoms, prevention treatment and control measures. This is a disease that is reportable to the Provincial Veterinarian because it can infect most animals including cattle, poultry, swine, sheep and humans, and because it is resistant to multiple antibiotics. Preventative measures include hygiene controls such as removing manure from areas where the cattle congregate, preventing manure from contaminating feed and water sources, and restricting contact with other possible carrier species such as wild birds, mice, dogs and cats.
Infectious Bovine Rhinotracheitis (IBR)
A brief explanation of Infectious bovine rhinotracheitis (IBR), a highly contagious viral infection of cattle, with symptoms, treatment protocols and prevention measures. IBR has five distinct disease syndromes with the most common and severe form being respiratory disease and its subsequent secondary bacterial infections. Preventative measures include several forms of vaccination, however timing is critical for these vaccines to be effective.
Infectious Bovine Rhinotracheitis (IBR) Update
An update summarizing developments in the occurrence of IBR in feedlots and research on newer, more effective vaccines for the disease. Evidence of a new virulent variant of IBR affecting previously immunized feedlot cattle has surfaced, prompting an earlier revaccination regime. Also of significance is the development of newer, more effective forms of BVH-1 vaccines. These include a modified live vaccine with gene-deleted mutants, and better delivery methods for DNA vaccines which include a DNA fragment that direct the production of protective antigens in the hosts’ cells.
Bovine Respiratory Syncytial Virus
An overview of the Bovine respiratory syncytial virus (BRSV), a viral respiratory infection that affects all ages of cattle but is more severe in young calves. Symptoms of a BRSV infection include mucous discharge, increased temperature and increased respiration leading to difficulty breathing. Treatment is supportive but includes the administration of antibiotics for secondary infections and anti-inflammatory drugs. Protection from the virus is provided by vaccination, however it is short lived and revaccination must be regular.
‘Atypical’ Interstitial Pneumonias in Feedlot Cattle
A description of ‘Atypical’ interstitial pneumonia (AIP), a lung disease of unknown origin that attacks more mature feedlot cattle, thus producing significant losses. It is a condition where fluids and white blood cells accumulate in the walls of the air sacs of a lung, interfering with gas exchange. Symptoms are few - affected cattle may be found dead without showing any signs of the disease, or they may show labored and rapid breathing a few hours before death. Contributing factors suspected in many cases do not apply to Alberta feedlot cattle, and a specific cause of the disease and preventative strategies cannot be determined.
‘Atypical’ Interstitial Pneumonias in Feedlot Cattle Update
A disease update documenting research on ‘Atypical’ interstitial pneumonia (AIP) in southern Alberta feedlot cattle. In this study, the incidence of AIP was higher in heifers near the end of their finishing period and on an 80% barley grain finishing diet than in steers. A possible relationship of AIP to the presence of 3-methylindole (3MI metabolites) has been noted, but the disease appears to be related to an interplay of feed intake, feed composition, sex and physiological maturity of the animal and possible environmental triggers.
An overview of the bacterial disease Hemophilosis (caused by the organism Haemophilus somnus), a common infectious disease that affects feeder calves from large feedlots in fall and winter. The disease is commonly known as “sleeping sickness” but can also manifest itself in infections of the heart, lung, ears and eyes, reproductive problems and polyarthritis. Hemophilosis can be successfully treated by most broad-spectrum antimicrobials; also, vaccination or prophylactic antimicrobial medication upon arrival at the feedlot can be used as preventative therapies.
Lameness in Feedlot Cattle
A brief synopsis with illustrations of two major diseases that are responsible for lameness in feedlot cattle – laminitis and foot rot. Laminitis, or founder, is caused by poisons which form in the rumen and then are released into the bloodstream following rapid changes in diet. Several major risk factors are involved in the development of the disease including energy (TDN), amount and quality of forage consumed, protein, particle size, nitrates and the addition of buffers. Effective control is presented by an optimally efficient feedlot ration.
Foot rot is characterized by rapid swelling, considerable pain and acute lameness, with the skin between the claws rotting and producing a foul smell. It is caused by bacteria entering abrasions between the claws and can be treated by antibiotics and sulfa drugs.
Feedlot or Grain Bloat
A summary of the primary reasons behind feedlot or grain bloat, which is a major cause of sudden death of feedlot cattle. It occurs in cattle on a high-grain, low-roughage diet, where the digestion of finely ground grain results in the production of frothy, viscous rumen contents which the animal is unable to expel by burping. Treatment depends on the severity of the bloat and can vary from walking the animal until it burps in mild cases, to the administration of antifoaming agents, to puncturing the distended flank and relieving pressure in severe cases. Prevention of feedlot bloat can be provided by controlling the particle size of the ration and by the addition of feed additives such a monensin or lasalocid.
A look at the management and control of frothy bloat, a potential hazard that occurs with intensive grazing in alfalfa and clover based pastures. Management practices aimed at minimizing losses from bloat include introducing cattle to a high-risk pasture when it is dry, making sure their stomachs are full with dry feed, and avoiding discontinuous grazing. Rotational grazing is one method of reducing the risk because it eliminates selective grazing and pastures can be selected when they are past the high-risk pre-bloom stage. Another important management tool is the use of ionophores which alter the rumen’s fermentation process.
An examination of the causes of grain overload in feedlot cattle which occurs following the accidental consumption of toxic levels of grain. Subclinical and clinical grain overload are characterized by the production of excessive quantities of acid and bacterial slime in the rumen resulting in losses from reduced feed intake, bloat and liver abscesses. Proper selection of type of cereal grain and processing method, increased levels of forage in the diet and gradual adaptation to a finishing diet are management strategies that will aid in the prevention of grain overload.
Polioencephalomalacia (Cerebrocortical Necrosis or Polio)
A description and treatment protocol for Polioencephalomalacia, a serious disease of the central nervous system of cattle, the result of an insufficient amount of the B vitamin, thiamine in the rumen. The condition is characterized by a sudden onset of blindness, muscle tremors, frothy salivation and head pressing, followed by irritation and convulsions. Prevention includes the supplementation of thiamine in the feedlot diet, a measure that would also give the added benefit in many cases of increased daily gain.
Bovine Viral Diarrhea (BVD)
A brief review of the Bovine viral diarrhea virus (BVDV), a widespread disease affecting cattle of all ages. The disease is divided into Type I and Type II viruses, each with many strains, and into prenatal infections (infections of the unborn calf) and postnatal infections (acute infections after birth). It is characterized by fetal infections, abortions, persistently infected calves that become carriers, mild and severe acute infections and mucosal disease; and is considered a contributing agent to shipping fever in calves. Prevention and control of the disease involve the elimination of BVDV carrier animals and vaccination of breeding cattle.
Bovine Viral Diarrhea (BVD) Update
An update summarizing developments that recognized antigenic differences between type 1 and type 2 BVD viruses. This followed outbreaks of severe acute BVD caused by a virulent type 2 virus that involved high economic losses in herds from fever, pneumonia, diarrhea and sudden death. As a result both killed and modified-live type 2 BVD virus vaccines have been developed.
Urolithiasis (Water Belly) in Cattle
An explanation of urolithiasis in cattle, a condition that results from a blockage of the urinary tract by a calculus (stone). Prolonged blockage can result in a perforation of the urethra of the penis or a rupture of the bladder, causing urine to build up under the belly skin or in the abdominal cavity (water belly). Treatment will vary according to what stage the condition has progressed to, and ranges from simply removing the stone to amputation of the penis and an attempt to repair the bladder. Preventative measures include providing an ample supply of fresh, clean water to maintain urine flow; deferring castration of bull calves to allow the penis and urethra to develop to a larger size and controlling the amount of phosphorus in feedlot rations by adding limestone to the ration.
An overview of a set of bacterial infections caused by the clostridial group of organisms which include diseases such as blackleg, bacillary hemoglobinuria (red water disease), and tetanus (lockjaw) and which are characterized by sudden onset, short duration and high death rate. The organism enters the body through wounds and contaminated feed as active bacteria or spores; and upon entering the body and multiplying produces a variety of toxins that kill cells and destroy tissues. Treatment of these diseases is difficult because very often the animal is found dead, but protection can be provided by vaccinations.
Buller Steer Syndrome
A description of the buller steer syndrome, a behavioral problem among feedlot steers that can result in injuries, weight loss, exhaustion occasional death; and which can be responsible for a large financial cost to the feedlot. The condition is characterized by the repeated mounting of a steer by a group of steers that persistently follow and perform the mounting behaviour. Factors implicated with the syndrome include the use of anabolic agents, incorrect implanting, group size within the pen and aggressive social dominance behavior. Effective treatment involves immediate removal of the steers being ridden and placement in a hospital pen. Preventative recommendations include the installation of overhead physical features attached to the pen, reducing the number of animals per pen and implanting upon arrival at the feedlot.
Coccidiosis in Cattle
Description and lifecycle of coccidiosis, a common parasitic disease of cattle. Coccidiosis is spread through oocysts contained in the manure of infected cattle and ingested through contaminated feed or water. Depending on the severity of the infection, symptoms vary from watery manure to one containing blood, and include dehydration, weight loss, depression, loss of appetite and occasionally death. Management principles include the protection of feed and drinking water from contamination, the provision of dry bedding and the isolation and treatment of infected animals. A table containing treatments and dosage protocols is included.
An assessment of trials examining the cost effectiveness of deworming programs for feedlot cattle. It was found that younger cattle with less developed immunity and cattle coming off pasture had higher parasite levels, and would derive a greater benefit from a deworming program. It was concluded that the deworming of fall placed cattle (calves and yearlings) would be cost effective, and that a strategic deworming program should be used with animals arriving at the feedlot at other times of the year.
Giardiasis and Cryptosporidiosis
A review of the common parasitic protozoan infection, Giardia duodenalis and Cryptosporidium parvum, both of which infect multiple species including humans. Both organisms cause damage to the small intestinal mucosal surface and are characterized by moderate to severe diarrhea with occasional mortalities. Giardiasis infects calves at about four weeks of age and can be chronic, while Cryptosporidium occurs in calves between one and three weeks of age and lasts for one to two weeks.
Cattle Grub (warble) Control for Feedlot Cattle
A review of the life cycle and parasitic stages of the species of cattle grubs (warble flies) that infect Canadian cattle resulting in major losses to the industry. These are the common cattle grub and the northern cattle grub. Both species have similar life cycles but exhibit differences in behavior of the female flies, seasonal occurrence of each species and the migration route within the host. Direct effects of the cattle grub include reduction in weight gain and milk production, while indirect effects include damage to the carcass and hides from grub infestations. Included is a table of cattle grub control products, their active ingredients and method of administration.
Pinkeye and Other Eye Problems for Feedlot Cattle
A review of the three main causes of eye problems (conjunctivitis) that affect feedlot cattle and the importance of proper diagnosis. They are ‘Pinkeye’ (Infectious bovine keratoconjunctivitis), Infectious bovine rhinotracheitis (IBR), and foreign bodies in the eye such as barley awns, chaff or dust. Symptoms of each problem are presented along with contributing organisms, recommended treatments and suggested ways of correctly differentiating between the conditions.
Lice Management for Feedlot Cattle
Description and life cycles of the two main types of lice that affect feedlot cattle in Alberta: the sucking lice which feed by inserting the mouth parts into the upper layers of skin, and the chewing lice which feed on dead skin, hair and other debris on the skin surface. Symptoms of louse infection range from excessive licking and scratching to hair loss. An effective louse management program includes adequate nutrition and the provision of shelter and clean, dry bedding. A table is provided listing louse control products, their active ingredients and administration.
Stable Fly Management for Feedlot Cattle
A review of the life cycle and behavior of the stable fly, an important pest of feedlots in Alberta. Both the male and female flies feed on blood and attack a variety of sources including cattle, horses, people, dogs and swine. Repeated bites will cause livestock to exhibit such behavior as foot stomping, tail switching, bunching behavior or standing in water to dislodge the flies. This can lead to severe economic losses through weight gain depression. Sanitation must be the first step in fly control – areas must be cleaned regularly and manure removed or mounded and packed. Residual sprays on surfaces such as fences, feed bunks, buildings and surrounding vegetation can help control the problem. A table is included listing fly control products.