SAN ANTONIO, Texas — Calf health is the number one priority for success on a beef operation.
The top third of producers invest the most in genetics, nutrition and animal health.
They do not cut back on feed because they do not want calves to lose weight, said veterinarian Joe Gillespie of Boehringer Ingelheim.
On average, animal health is less than five percent of the cost of production, but that is where people often cut back to save money.
“If you get them sick they are going to lose weight. Take those three things into consideration,” he said at a calf health session at the recent National Cattlemen’s Beef Association convention held in San Antonio, Texas.
“No matter what you add or subtract from your production system, make sure that you get some return on investment. Sometimes you can spend the most and get the most. Sometimes you can spend the least and lose the most,” he said.
Management varies across operations, but there are some basic principles in animal health.
Calves that receive adequate colostrum within the first two hours of life are given the best start.
Immunity protection for baby calves comes from the first drinks of colostrum, in which the mother delivers antibodies for disease protection.
“It is the most important drink in his life,” said Gillespie.
There are consequences if the calf had a difficult birth, does not nurse right away and does not receive 150 grams of immunoglobulins to support its immune system.
It needs to get colostrum within two hours. It is best if it comes from its mother or another cow on the property that calved at the same time.
When a calf is born its digestive tract is porous like cheese cloth, which allows it to absorb immunoglobulins. That tract closes in 24 hours and the ability to absorb it is lost.
Calves that are colostrum deficient have a greater risk of death before weaning and probably carry that weak immunity with them to the feedlot.
Bovine respiratory disease is the leading cause of death among calves older than three weeks, he said.
Studies have shown BRD is responsible for 16 percent of deaths in the first 180 days of life.
“We have to consider how we make management plans for health in our herds,” he said.
Producers trying to keep problems like BRD under control need to think about the pathogens responsible for causing disease, commingling, the environment and handling stress of the cows and calves. Stressors such as temperature swings and moisture are out of a producer’s control.
Vaccination is one way to ensure better health.
“The vaccine you give to your cow and the timing of that vaccine is what helps that cow have protection, but also she has the ability to pass that on to her calf,” he said.
“We need to consider whether that vaccine is efficacious in our cow herd based on how we manage them.”
Vaccines for conditions such as bovine viral disease have been available since the 1970s, but the same prevalence continues.
BVD is an ongoing problem with different disease-causing strains of Type 1A, 1B and Type 2. Vaccines are expected to provide cross protection, but they don’t all work in the same way. In the U.S. it is thought about half a percent are born persistently infected so the disease still spreads.
Vaccines are also needed for IBR, bovine herpes virus, parainfluenza and bovine respiratory syncytial virus, as well as bacteria like Mannheima haemolytica and pasteurella multocidia. These latter two are the primary causes of bacterial pneumonia in calves, especially around weaning or in summer.
Histophilus somni causes respiratory infection that needs treatment.
Leptospirosis causes venereal disease in cows and pneumonia in calves.
Mycoplasma species are opportunistic bacteria responsible for swollen joints, tilted heads because of ear infections and probably death. It may occur along with BVD. There is no vaccine.
Calves with poor colostrum intake are at risk for mycoplasma.
“If the calf is in good health and has a good immune function, he can fight that off. If he doesn’t, you are up for a battle,” he said.
Cattle need annual vaccinations, but management varies across the country.
“If you are not vaccinating cows today, please do something because your calf needs it,” he said.
Killed vaccines are safe for any animal at any age. Modified live vaccines should not be given to pregnant animals because there is an abortion risk. These should be given before turning cows out with the bulls.
Modified live vaccines typically mount a stronger immune response so consult with the local veterinarian and read the product label to understand what is being given and what protection is offered.
Try to vaccinate calves before they lose passive immunity. This could be two to eight months of age.
Parasites also lower immunity.
Producers tend to focus on parasites such as flies and lice because they can see them, but the internal ones affect the calf’s health and ability to fight off other diseases.
Parasites in the gut can cause irritation and discomfort. There is a loss of appetite and decreased weight gain. It also affects their immune function because they are not strong.
Assessing the level of parasite fecal egg counts can be done by collecting manure samples for testing.
A low burden of 50 eggs per gram of manure translates into as many as 7,000 worms in the intestinal tract. A high load of 150 eggs per gram equals 20,000 worms in the intestinal lining.
Parasites can be a problem when calves are growing and on grass during the late spring and summer months.
“If you think it is too arid or too cold or too hot, there is still a risk of parasites,” he said.
Rainfall is necessary for the development and survival of the larvae. It also disperses them onto the grass.
Adult parasites drop eggs in the manure. That egg can live up to several years and when conditions are right, the offspring can emerge.
Moisture and timing are critical so talk to a local veterinarian about what is present and how to reduce the risk using commercial treatments and different pasture management.
Complete information on parasites in Canada may be found at www.beefresearch.ca/research-topic.cfm/intern.
Common parasites in Canada
Roundworms: Brown stomach worm, instestinal worms
Roundworms are the most common class of internal parasites in beef cattle and impacts can be insidious. They cause depressed weight gains, poor feed efficiency, diarrhea in calves and reduced milk production and reproductive inefficiency in cows.
Lungworms Sporadic disease outbreaks
Lungworms in upper airways of the respiratory system cause nasal discharge, coughing and difficult breathing. It is a sporadic disease in Canada but can be severe, affecting both calves and adult cattle.
Fascioloides magna has a regional distribution (eg. Foothills of Rockies, Great Lakes). It is carried by elk/deer and transmitted in wet, boggy areas via semi-aquatic snails. It causes liver condemnation and its impact on production is poorly defined.
Tapeworms are several metres long and are common. Segments can often be seen in manure but are not considered harmful.
Coccidiosis is caused by single celled parasites that invade and destroy cells lining the intestine. It is very common in Canada, causing acute dysentery and diarrhea, neurological signs, chronic diarrhea and reduced growth. The disease most commonly occurs in one-to six-month-old calves.
There are two types of lice: biting and sucking lice. Numbers increase with cooler temperatures reaching maximum levels in late winter. Lice cause coat discolouration and hair loss, and sometimes anemia and production loss.
They typically affect confined livestock, but can also occur on pasture. Bites are painful and often bleed. This results in pain and decreased production due to reduced grazing/feeding, and animal fatigue from attempts to dislodge insects.
Horn flies congregate around and on cattle at pasture all summer. They bite and suck blood, affecting livestock behaviour, causing reduced performance and reduced milk production.
Ivermectin has reduced the prevalence of cattle grubs in Canada to very low levels but they are still present in localized areas. Adult female flies lay eggs in the hair of the animal, which hatch into grubs and migrate deep into the tissues where a painful warble develops that causes pain to animals and holes in the tissue.
Source: Beef Cattle Research Council