Risk management reaches beyond financesWritten by Saige Albert
“We want to minimize all the potential risks that can happen to our herd,” said Rood at the Wyoming Stock Growers Association Winter Roundup on Dec. 13. “When we talk about animal health, we’re really talking about risk management.”
Rood explained that producers tend to focus on the dead animals, aborted calves and open cows, but he says usually there is something going on sub-clinically in the herd.
“When we see dead animals, there are probably others that are sick and we don’t know,” said Rood. “I would argue those might be worse for the herd.”
Rood identified three factors to getting disease: pathogenic organisms, the host and the environment.
Using tetanus shots as an example, Rood explained that horses receive a tetanus shot once a year, while humans only receive the vaccination once a decade, usually.
“What’s the difference? We’ve got a similar bacteria, and the host immunology is pretty much the same,” said Rood, “but we’re not rubbing our tails against a rusty nail on the fence. The environment is different.”
He continued, explaining that outbreaks of health problems, such as calf scours, are likely linked to the environment, particularly if animals are kept in the same areas from year to year.
“Think about the environment,” he encouraged. “I think it goes overlooked too often.”
Animal health risk management also includes disease prevention strategies such as vaccination and parasite control, as well as genetics, nutrition and welfare.
“Don’t underestimate the genetics. There is a future in terms of the scientific advancement of genetics,” commented Rood. “Today we think of hide color or polled, but will we see feed efficiency, parasite resistance and disease resistance in the future?”
“Nutrition is very key,” said Rood, noting that levels of IgG and IgE, antibodies that contribute to the immune response were high in animals with a good body condition score.
For calves, Rood noted nutrition means consuming colostrum multiple times within the first six to 12 hours after birth. Colostrum provides calves with a form of passive immunity, or maternal immunity, meaning that the antibodies from the maternal immune system are passed to the calf through the milk.
“The calf is born with very few antibodies, if any,” said Rood, explaining that as the calf ages it will also begin to acquire active immunity, which consists of self-generated antibodies.
Maternal immunity starts high, but decreases steadily and disappears at weaning when the calf is no longer nursing. Additionally, as the calf ages its ability to absorb antibodies from milk decreases. Those antibodies present in the system also begin to degrade as they age. Passive immunity can be influenced with vaccination of the dam prior to birth.
“If we give the mother some vaccination before she gives birth, her milk will be more rich in antibodies – it will be better quality,” said Rood. “There are products out there that we can give a cow to boost and help her milk have more antibodies in it.
Vaccinating at a younger age can also influence the active immunity of calves.
“Vaccinating primes the immune system to get it going,” explained Rood, adding that misconceptions about maternal influence previously indicated that vaccines should not be given too early.
“We can give vaccines sooner than we thought we could,” said Rood. “Calves that were given a vaccine young develop a memory response, and they respond really well when they get to the feedlot later in life.”
“Vaccines are not 100 percent effective, but we have some really good ones,” said Rood. “We need to use them in conjunction with other management practices.”
Rood added utilizing the right vaccines and following labels is important.
“Keep in mind that some vaccines require a booster, particularly the killed vaccines,” said Rood. “If we don’t booster our calves and wonder why they get sick with summer pneumonia, it’s not the vaccine’s fault – it’s our management.”
Stress management when working cattle or utilizing animals is also important to consider under ranch management practices to alleviate disease potential.
“Stress is probably the biggest reason for vaccine failure as it relates to protection against viral diseases,” mentioned Rood. “Some stress might be a good thing and it will help you. Prolonged stress, however, is not.”
Rood continued that the steroid released as a result of stress is adrenal cortisol, and it can cause immune suppression, which makes animals under stress subject to disease. For example, he explained that in last spring’s outbreak of equine herpes virus, the infected animals were those in high stress competition situations, making them more susceptible because of a weakened immune system.
In choosing vaccines, options include utilizing a modified live vaccine or a killed vaccine, and each has advantages and disadvantages.
“Modified live vaccines are living, growing viruses. The theory is to have one that divides, multiplies and replenishes itself but doesn’t cause disease,” explained Rood. “They stimulate a really good immune system.”
With modified live vaccines, Rood cautioned producers to read the label, noting that they shouldn’t vaccinate cows for the first time with a modified live vaccine when they are pregnant because of the risk of abortion.
“Killed vaccines also stimulate the immune system, and they do a good job, but they have to be boostered,” said Rood. “They also have to have a good adjuvant.”
The adjuvant serves to present the vaccine to the body so it can be recognized by the immune system. Each company has their own proprietary adjuvants with different qualities.
“One of the advantages I see with using a killed vaccine is there is less concern about the state of pregnancy, but often they require a booster,” commented Rood. “With the modified live vaccines, there is a limited amount of time that the vaccine will be effective after the components are mixed.”
Regardless of the vaccine selection each producer chooses, Rood mentioned that any concerns should be addressed with a veterinarian. He also mentioned that simply giving the animal a shot doesn’t guarantee efficacy, and proper administration and management is paramount.
“If you vaccinate calves, prove it, verify it and enroll in a program,” added Rood. “Be proud of vaccinating and market your animals as part of a preconditioning program. Hopefully, you can receive a premium.”