Fall preg checking provides convenient time to evaluate body condition for calvingWritten by Emilee Gibb
As many cattle operations begin pregnancy checking their bred cows this fall, producers also have the opportunity to evaluate body condition and determine if different management strategies are needed before winter begins.
In a webinar discussing how to improve weaning weights, conception rates and calf health, Saskatchewan Regional Livestock Specialist Naomi Paley urged producers to consider the long-term impacts that body condition has on rebreeding, weaning weights of the current year’s calf crop and weaning weights of future year’s calf crops.
Ideally, Paley suggested that producers evaluate their animals hands-on and assign body condition scores at least three times per year.
“If we can at least get our hands on them once or even twice during the year, that’s a benefit, and we’re going to be able to use that information to help us be a better manager,” said Paley.
Fall is a convenient and important time to evaluate body condition, continued Paley.
“The fall time is a good time to evaluate body condition, when we’re processing cattle or running them through the chutes. In the fall, we really want to have those cows in good shape,” she said.
Paley advised producers to consider feed costs when looking at maintaining or adding weight to an animal.
“It’s more expensive to put weight on a cow during the winter than it is to maintain her in good condition,” she said. “Our feed costs are higher for that cow if we’re trying to put condition on her during the winter, and it’s also biologically expensive.”
An average 1,350-pound cow needs to gain 200 pounds of fat to increase one full body condition score.
Adding 200 pounds would equate to 25 bushels of barley or 2,000 pounds of high-quality hay.
“There’s definitely a feed cost associated with trying to put body condition back on to a cow and get caught back up to where she needs to be to have a healthy calf and rebreed in a timely manner,” continued Paley.
“There are those who think that burning body condition or burning some backfat off of the cow is a good way to try and make use of extra reserves that the cow has and that they can sort of bank on that,” said Paley.
However, she noted, “There are some biological costs associated with that.”
A cow receives approximately 900 megacalories of energy for every unit of body condition that is lost. Alternatively, it takes about 1,200 megacalories of energy for the cow to gain one unit of condition.
The extra biological cost of gaining weight back results in a loss of efficiency of approximately 50 percent, explained Paley.
“We can see that it’s a really inefficient system, and it’s going to end up costing us in the end one way or another when we’re counting on sort of farming the fat off of the back,” she said.
Growth and health
During calving and lactation, cow body condition has a significant impact on calf health and growth.
Cows that are below desirable body condition at calving or losing condition after calving may have a five to 25 percent reduction in calf weaning weight, said Paley.
“This is largely due to the reduced nutritional value of the cow’s milk and the amount of nutrition the calf is receiving during the nursing period,” she continued.
Because of the reduced nutritional value of the milk, the calf’s immunity will be suppressed. Reduced immunity combined with reduced weight gain because of lower milk production can ultimately lead to lower weaning weights, Paley explained.
Body condition at calving and throughout lactation is important for timely rebreeding, said Paley.
“Contrary to some management systems, the goal is not simply to get our cows bred. We want them bred early,” she emphasized.
Every time a cow misses a cycle or doesn’t become pregnant has a direct impact on weaning weight of the calf.
“Every time a cow misses a cycle or doesn’t get bred on a cycle, she remains open, so the calf is 20 days younger,” said Paley. “If our calves usually gain about two pounds a day, it’s 40 pounds lighter, which can account for a $90 per head loss every time a cow skips a cycle and doesn’t get bred.”
Economics of preg checking: Testing continues to be vialbe in declining cattle marketsWritten by Emilee Gibb
Cull cows account for 15 to 30 percent of a cow/calf producer’s income, making their management a crucial aspect for producers to consider.
“Management of cull cows is not an insignificant aspect of a producer’s income. Each year, producers are faced with the decision to preg-check or not and this can really make an impact on the bottom line,” said Canfax Research Services Manager Brenna Grant.
In a webinar by the Beef Cattle Research Council titled “The Economics of Pregnancy Detection,” Grant discussed the impacts of the current cattle markets on the economic viability of pregnancy testing in cow/calf operations.
There are three main options for producers to choose from when culling cows from their herd.
The first option is pregnancy checking and then culling in the fall, which is beneficial for reducing feed costs over winter.
“This has the benefits for the producer of providing cash flow and minimizing additional overhead costs associated with keeping those animals over the winter,” said Grant.
The second option producers can choose is short-term feeding. Producers pregnancy check their animals but separate the cull animals from the herd to supplement with a high energy ration for a short period of time to add weight.
“This means that they not only get a higher price when the markets are out of fall low prices, but producers also get added pounds sold,” she explained.
The final option is overwintering cattle and selling the cull cows in the spring. This option avoids pregnancy testing.
According to Grant, several factors influence the economics of pregnancy checking.
“The economics of preg-checking are really dependent on the cull cow market price,” she said.
Winter management strategies also influence the economic viability of pregnancy checking.
“This is really going to impact what our yardage is, as well as our feed costs,” said Grant. “That winter management system is also going to have implications on what our average daily gain is and the final weight of those animals.”
While it plays a role, Grant’s study did not find that veterinary costs were a large economic factor.
“This is one cost that’s been brought up in the literature quite a bit, but we found, when we looked at the model, it’s a really minor aspect of the equation,” she commented.
A test model was created to compare the three culling options. The purpose of the model was to determine how to maximize value.
“This whole model is really set up with the premise that, instead of minimizing cost, we want to maximize value for the producer,” explained Grant.
Grant’s research determined that cull cow body condition in the fall is a significant driver in deciding whether or not to pregnancy check.
“If they’re fat from being on grass all summer and there’s very little potential of additional weight gain over the winter, we’re maybe not going to see much benefit because we’re really only gaining that seasonal price variation,” she said.
However, if cows are thinner and have the potential to gain weight, overwintering or short-term feeding may be a more viable option.
“We’re not just going to have the additional pounds sold, we’re going to have the seasonal price increase, as well as potentially increasing quality grades,” noted Grant.
The type of winter management system that a producer uses impacts the economic viability of pregnancy checking.
“The higher a producer’s feed and overwintering costs, the more favorable preg-checking and culling cows in the fall is,” said Grant.
She explained that costs can be offset by cow performance and will vary from operation to operation. It is important to note that even if feed costs are low, if average daily gain is minimal, it will offset some of the advantages.
Ultimately, cow prices are one of the largest factors in choosing a culling option. A threshold point of $1.20 per pound is important for producers to consider when making a decision.
“If prices are lower than this, it actually encourages producers to preg-check and cull in the fall,” explained Grant.
In most scenarios run in the model, short-term feeding showed the greatest economic benefit for producers.
“The only case when separating cull cows was a less favorable option is when the overhead costs of separating them and feeding them separately was very high or the number of days on feed was really low,” she said.
As cow market prices have peaked and come back down, Grant emphasized the importance of the counter-seasonal year that was observed last year.
“Last winter was the first time that were in a bear run and cow prices actually dropped from the fall going into the spring,” said Grant.
In a situation where prices are increasing, pregnancy checking does not prove to be economically viable. However, in markets that are decreasing, it becomes more economically viable to pregnancy check and cull in the fall.
“With increasing prices, preg-checking is obviously a negative option, but that’s not the case in decreasing prices when comparing overwintering or short-term feeding compared to preg-checking. Basically we’ve got declining prices to encourage preg-checking based on our economic gains,” she said.
Grant concluded that pregnancy testing is currently the most viable option for producers to consider.
“As we come back into a price situation with lower cull cow prices, preg-checking does make sense,” comments Grant.
Simple steps improve the chance of compromised calves to reach weaningWritten by Saige Albert
When calves are born with dystocia, Frank Garry, veterinarian, notes that producers can play an active role to help save their lives with several steps.
“My advice is that any calf born with any degree of dystocia might need our help,” he adds. “Calves should be born from an uncomplicated vaginal delivery. Even if they look ok, historically, calves born with any trouble are more challenged than normal calves.”
Garry also notes that calves born to heifers may need additional help because heifers may be incapable of providing the good mothering that calves need.
“Good calf management will help that,” Garry comments.
Research out of the Netherlands assessed that the amount of time it took a calf to properly orient its head and move onto its sternum, the time it took to attempt to stand and the time it took to stand.
“Healthy calves should put their head right in three minutes, move onto their sternum in five minutes, attempt to stand in 20 minutes and stand in 60 minutes,” Garry says. “These are easy things to measure.”
Calves that took longer than 15 minutes to move to their sternum were 84 percent more likely to die.
“Active suckling should take place in less than two hours,” he adds, “and the calves should be attentive, responsive and active.”
In a normal routine, calves will also receive good mothering from their dam, but occasionally – and especially with heifers, maternal instinct is lacking.
“We select for maternal instinct, but the cow also has to learn,” Garry says. “There is also a thin line between mothering and aggression.”
Heifers that are unsure of what to do either reject their calf or beat it up.
“After their second calf, good mommas can help take care of the liabilities our calves may experience,” he says. “They push it, nudge it, lick it and dry it to make sure the calves responds.”
Mother cows also lick their calf on the butt to encourage nursing.
“If the dam doesn’t do these things, we may need to supplement what the dam does or replace her,” Garry comments. “We should also do what the dam is supposed to – rub it on the butt, so it will put its head out and start looking for food.”
To help calves born with any problems, Garry encourages producers to follow a series of steps to improve their chances.
“These are things that many ranchers already know, and they should be prepared to do them all in synchrony,” he says. “We should help the calf maintain body temperature, increase blood volume, provide energy to the calf and oxygenate the blood.”
If calves are pulled, Garry mentions that producers should monitor them for at least 20 minutes.
“Calves might move well at the beginning because they are punch-drunk on adrenaline,” he says. “In 15 to 17 minutes, we should assume the calf is going to get quieter.”
If calves aren’t moving to the sternum within the first 15 minutes after birth, Garry says producers should position them in sternal recumbancy and get the mucus out of the airway to help them to breathe.
By posing calves on their sternum, the lungs are vertical rather than horizontal, enabling them to breathe easier.
“It also does something else – it pisses the calf off,” Garry comments. “They don’t like it, but it is what a good mom would do.”
“Then we have to stimulate it to breathe,” he adds. “Most people do this by tickling the nostrils.”
Garry advocates using an oxygen tube and administering oxygen to compromised calves. When administering oxygen, he notes that a tube should be inserted up the nose of the calf but not beyond the level of the eye to avoid channeling oxygen to the stomach.
“We have oxygen tanks on our places because most of us have oxy-acetylene torches,” he says. “Adjust the oxygen to an appropriate rate. If we don’t have a flow meter, adjust it so it makes our cheek cool.”
He adds, “Make sure the oxygen doesn’t go into the belly and that it gets to the lungs.”
“Calves that don’t have a normal body temperature need our help,” says Garry. “It is simple to do.”
Garry also notes that the body temperature of a calf should not drop below 101 degrees.
“Calves are born at about 104 degrees,” he says. “In the first half hour, it will drop to 101, but if it keeps going down, something is wrong.”
He encourages producers to take the temperature of calves that are doing poorly to make sure their body temperature isn’t too low.
Calves maintain their body temperature by generating heat, but if the calf is losing too much heat, it can be difficult.
“We want the calf on a dry surface, and we want to provide supplemental heat,” he says, noting that producers may use heaters, hot water bottles or warming huts. “Another way is to provide the calf with a hot drink or warm it with a hair dryer. We can also provide heat lamps. All of these are options, depending on how bad our calf is.”
Finally, Garry mentions that calves must consume colostrum to provide immunoglobulin, micronutrients, fluids and warmth.
“We want to stimulate and enhance respiration, maintain body temperature and provide energy,” he says. “Those are the key things to taking care of physiologically challenged calves.”
Garry spoke in mid-November 2015 during the Range Beef Cow Symposium in Loveland, Colo.
Diseases can result in abortions, decreasing revenues for cattle producersWritten by Saige Albert
Kansas State University Veterinarian Bob Larson says, “If my cows are working and my bulls are working, if we run into a disease that kills pregnancies, that will kill our momentum, as well.”
Live calves bring revenue to the farm and ranch, and he notes that diseases like infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea can cause abortions and decrease profits for producers.
“IBR and BVD are two of the most common causes of abortion that we deal with,” Larson comments. “The good news is, we have effective vaccines for both of those diseases.”
“IBR is a herpes virus,” Larson says. “That means it is a really common disease, and it is secreted by any fluids. It is easily passed from one cow to the next.”
IBR also results in a lifelong infection in the animal. Infected animals will likely exhibit symptoms, such as a cough or runny eyes, the first time they are exposed. However, from that point forward, they will shed the virus during times of stress.
“They stop shedding the virus until they get stressed,” Larson explains. “If they get stressed during calving, while being moved or whatever, she’ll shed the virus and spread it around for a while.”
In feedlots, the disease is often called red nose.
“It is a really, really common virus,” Larson emphasizes.
While IBR is common, Larson notes that is can be a challenge because it presents mildly in adult cattle.
“They don’t get sick,” he says. “The calves go through it and get runny eye, and abortions don’t happen. They wait about two months.”
He also notes that signs in cows are very subtle.
“We may not see any signs or if we notice problems, we don’t think about them until two months later when the cows start slipping calves,” he says. “This is one of the problems. IBR causes problems.”
Larson further mentions that IBR is one of the major causes of abortion in the U.S. during the last half of gestation.
For producers who start seeing abortions and then remember having runny-eyed calves from the previous year, Larson says, “That makes me suspicious we have IBR.”
Necropsy and sending samples to the lab will confirm the disease.
Larson also notes, however, that vaccines for IBR and prevalent and effective.
“I like to give two modified live vaccines at weaning and breeding to try to set up some good immunity prior to the first breeding season,” he says. “Technically we shouldn’t need more than one, but there is value in making sure as many heifers respond as well as possible.”
He also notes that he prefers to vaccinate replacement heifers at the start of breeding and at preg-check time.
“I have a lot of tips, and I booster my cows once a year,” he says. “Producers should talk to their vet about their preference.”
He adds, “The one concern is that if I give a modified live vaccine to a pregnant cow that is naïve, I can abort her with the vaccine. However, most cows get vaccine or are naturally exposed, so a booster is not enough to cause them to abort.”
“They do need to be well vaccinated before they get pregnant,” Larson says.
“BVD is somewhat similar to IBR in that is it really common, but while there are a lot of cows persistently infected with IBR, only a very few calves carry the BVD virus,” Larson explains, noting that only four to six BVD persistently infected (PI) calves are expected for every 1,000 head that enter the feedlot. “The problem is, if cows aren’t spread out, a couple PI calves can come into contact with a lot of cows.”
He adds, that PI calves shed the BVD virus continually throughout their life, rather than only during times of stress, like with IBR.
“It doesn’t take much contact to get BVD,” he adds.
“If a cow is exposed to the virus during the first half of her pregnancy, one of two things will happen,” Larson says. “Either she’ll abort – and a lot of time she does, but if she doesn’t, the calf will get infected with BVD. If he survives, he will become PI with the virus.”
The source of the BVD virus is nearly always a PI calf. While some PI calves are poor-doing, others look healthy and stay in the herd.
“Our best estimate is about half of the PI calves die between birth and weaning,” he says. “Another half die between weaning and yearling age.”
Often BVD PI calves don’t make it to their first calf.
“It’s a common problem,” Larson says. “If she survives to have her first calf, it will always be a PI calf.”
With BVD, Larson says, “Pregnant cows exposed to BVD will either abort or create new PI calves for next year.”
While vaccines for BVD are available, Larson notes that no vaccine is perfect.
“If they were perfect, we wouldn’t talk about this disease,” he says. “However, if people have an abortion storm, I get to investigate it, and in all my years of looking at problems we trace back to BVD, they are almost always unvaccinated or poorly vaccinated herds.”
He also notes that it is important to follow vaccine protocols and to have a consistent program.
“If we only vaccinate some years or we don’t vaccinate at all, the immunity isn’t the same,” he says.
“Viral diseases are bad,” Larson comments. “They will always cause us some problems, but we have tools that make disease control possible.”
Larson spoke during a producer dinner in early March in Gillette. Boehringer Ingelheim Vetmedica sponsored the dinner.
Garry: Simple nursing technique decreases losses in compromised calvesWritten by Saige Albert
Every calf that is lost in a herd is a loss of 550 pounds of sellable weight, which cuts into profits, says veterinarian Frank Garry, who works in the Integrated Livestock Management Program at Colorado State University.
“We have already put input costs into that calf, so the only way to make it up is to increase the weight of the next 11 calves by 50 pounds,” he says. “That increase needs to be more if we are weaning calves at 600 pounds or more.”
He also notes that the majority of death loss for animals pre-weaning occurs when they are first born.
“This is not shocking or surprising, and it’s true for all mammals,” Garry explains. “The consistent trend is that about 50 percent of calf deaths occur in the first 24 hours and about 70 percent occur in the first three days. Almost all of those are attributable to physiological problems.”
Transition of birth
One of the reasons that death loss is so high after birth, according to Garry, is that birth is the single-most major transition that an animal will ever make.
“The transition from living inside the uterus to living outside the uterus is the single most major transition of physiologic function the animal will make until it dies,” he says. “It doesn’t always work well, and it isn’t always successful because a lot of complicated things are happening.”
Each system within the animal’s body must adapt within the first one to two minutes, he adds.
Garry looks at changes in the respiratory, cardiovascular and muscular systems changes that the animal must undergo at birth.
“The calf has never breathed in its whole life,” he says, adding that the heart and blood vessels have never worked in concert with the lungs to oxygenate the blood. “The calf has, for its entire existence, been taking energy from its mom. Within a few minutes, it has to start putting energy out. That is a radical transition for most animals.”
Thermoregulation is also an issue for newborn calves. Prior to birth, calves have never been responsible for maintaining their own body temperature.
“We also have to look at the muscular skeleton,” he says. “Calves move when they grow, but it isn’t the same as lifting a 70-pound body off the ground and moving around.”
“All of these things have to change, and they have to change right now,” Garry adds. “If they don’t, the calf dies.”
When calves breathe for the first time, Garry explains that they have to begin by expanding the lungs.
“The blood goes from the right side of the heart, through the pulmonary artery and into the lungs,” he says. “Then it goes from the pulmonary vein to the left side of the heart where it goes to the tissues to the rest of your body.”
As the blood returns from the right side of the heart to the left side, the calf must take several big breaths to expand the lungs and allow the blood to flow properly.
“Physical and muscular activity is critical,” Garry continues. “As the calf moves, it expands its lungs.”
This creates a vicious cycle, he adds, explaining that if the calf doesn’t have oxygen, it doesn’t have the strength to move, but if it doesn’t have the strength to move, it has trouble expanding its lungs fully.
“The calf has to be strong, active, vibrant and start moving, or it is in trouble,” he says.
Fluid and heat
The second consideration is fluids in the calf.
“Calves are always born with less whole blood volume than they really need to maintain good blood pressure,” Garry says. “When calves come out, they need to be dried off, and they need fluid immediately.”
Heat is the third component that is essential.
“The third item is to be able to generate body heat,” he explains. “There are three ways that can be done – non-shivering thermogenesis, shivering thermogenesis and physical activity.”
Non-shivering thermogenesis is metabolic activity, Garry notes. Brown fat, which makes up two percent of the body weight, is used to create energy and convert that energy to heat.
Shivering thermogenesis is heat generation through shivering, and he says, “We shiver to generate body heat.”
“The third mechanism is physical activity. That is the most profound way of generating heat,” Garry says. “Calves that are quiet and lie down don’t generate body heat, so they get cold faster.”
Each of the major components for calf survival are interconnected, Garry adds.
“If we have decreased activity and lethargy from a weak or compromised calf, the calf will have low blood oxygen, which makes the calf weak or further depressed,” he says. “The calf will also probably experience heat loss and have low body temperature.”
Calves with lower body temperature will struggle to oxygenate blood, further exacerbating calf health problems.
“Calves need warmth, and they need fluid,” Garry explains. “We need to maintain the physiologic integrity for the calf to stay alive.”
Garry spoke during the 2015 Range Beef Cow Symposium, held in mid-November 2015.