CALVES can experience depression and anxiety, according to research from the University of British Columbia (UBC), raising ethical concerns over cattle dehorning procedures.
Dairy producers dehorn cattle using a chemical paste or hot iron to reduce the risk of injury to farmers and other animals. Previous research on dehorning has shown that the procedure elicits behavioral and physiological responses in the animal, but little is known about the emotions it conjures, UBC said.
A study led by Heather Neave, one of the first researchers to use a cognitive test to address the emotional response to pain in any species besides humans, found that calves showed signs of pessimism after having their horns removed.
"The study shows they're not just animals who have a sensory response," said Neave, a recent master's graduate of UBC's Animal Welfare Program. "They possess the cognitive ability to pass judgment, interpreting ambiguous events more negatively."
At the UBC Dairy Research Centre in Agassiz, B.C., Neave spent three weeks training 17 calves to perform a simple task where they had to decide whether or not to approach a video monitor inside their pen, depending on the color displayed on the screen.
Using milk as a reward, half of the calves were trained to approach the monitor when it was red and avoid it when it was white. The other half learned the opposite. The calves quickly learned the suggested meaning of the two colors and were then introduced to three shades of pink that could be interpreted positively or negatively.
Neave ran the task with the calves before and after the calves were dehorned with a hot iron at 30 days of age. She found that the calves showed no change in their approach to the red or white screens, but they approached the ambiguous pink screens less frequently following the procedure, taking the dim view that they would not be rewarded with milk, the announcement said.
According to Neave, this pessimistic response shows that the calves are experiencing negative emotions.
"Statistical analysis refuted other plausible explanations for their reduced response to the ambiguous screens," Neave said. "Human literature indicates that emotions influence our interpretations and judgments of ambiguous information, which was a similar response exhibited by the calves.
"The feedback I get in conversation with dairy producers is positive," she said. "They are surprised to learn that calves are able to complete the task, and it really hits home for them when they realize the animals have an emotional response to the procedure.
"Some dairy farmers are now moving away from dehorning altogether by using genetically hornless animals in their herds," Neave said.
Other researchers at the center are using the same experiment to study the impact on calves of being separated from their mothers and to probe the potential benefits of the animals being housed with a partner.
Calf feeding programs
During cold weather, calves' energy requirements greatly increase, and calf starter consumption plays an important role in providing calves with the energy they need when they need it most.
"To keep calves growing all year long, regardless of the temperature outside, it is important that calf feeders pay attention to the details and closely monitor their feeding practices," Christie Underwood, a calf and heifer specialist with Purina Animal Nutrition, said.
Underwood offered some simple tips to help calf feeders make sure that the details of feeding calves don't fall through the cracks:
* Know how much calf starter is actually needed. Measuring calf starter is the best way to ensure that the correct amount is being fed. Calf managers should provide employees with guidelines on how much calf starter is appropriate for a given age.
Training employees on how to read buckets is another critical step in maintaining adequate feed intake. Underwood reminds employees to provide just enough calf starter so that there are no empty buckets prior to the next feeding.
"It's a balancing act between providing the right amount of calf starter and not providing too much," Underwood said. "As calf feeders develop an eye for how much calf starter is enough and how much is too much, they will be able to help save your operation from costs associated with wasted feed."
Paying close attention to how much calves are eating allows calf feeders to notice when a calf's intake is off. Then, more immediate action can be taken if the calf is sick, Underwood noted.
Calves' feeding needs are not universal across all operations. Breed, weather, season and the amount of milk or milk replacer fed can all affect the amount of calf starter needed to achieve optimal growth. As a result, it is important that calf feeders learn and apply what works best on each operation, Underwood said.
* Freshness is a must. Simply topping off calf starter buckets without routinely discarding leftover feed is a practice Underwood discourages because this may lead to moldy feed on the bottom of buckets. Mold can result from moisture in the air, precipitation or even the calf's muzzle.
If mold is present, calf starter consumption may be decreased and may even result in digestive upsets.
"Adding more calf starter on top of already wet or moldy feed can negatively affect calf health," Underwood said.
* Don't forget about water. Water plays an important role in calf starter consumption. If calves don't have enough water to help them consume calf starter, this may hinder their appetite. "Keeping fresh water in front of calves at all times is essential to achieve optimal calf starter intake," she said.
Calf feeders should be aware that as calves get older, water consumption increases. Lack of adequate water for older calves may lead to slug feeding of grain and subsequent digestive issues. When a calf does not have water or feed and suddenly is offered either, there may be a chance for the calf to consume a large amount of grain at once, which may lead to digestive bloat. Free-choice starter and water availability can help minimize the risk of digestive upsets in calves, Underwood noted.
It is no secret that calves are among the choosiest eaters on most dairies, and they thrive on consistent routines. To keep calves growing and developing to become profitable members of the lactating herd, consider routinely evaluating the operation's feeding practices, and make sure all employees are on the same page.
Fresh cow health
Maintaining healthy fresh cows is among the top 10 most important factors that can affect a dairy operation's financial performance, according to dairy consultant Greg Bethard of G&R Dairy Consulting in Blacksburg, Va.
Bethard said fresh cow health "sets the table for everything else on a dairy," including milk production, income over feed costs, pregnancy generation and cow flow. He discussed the "keys" to a dairy's financial health during a preconference symposium sponsored by Prince Agri Products Inc. at the recent Penn State Dairy Cattle Nutrition Workshop.
"It's really difficult to have a profitable dairy with fresh cows that aren't healthy," he said. "It drives overall herd health, predicts the near-term future and impacts employee morale in a big way."
Supporting his comments, other preconference symposium presenters discussed the negative effects of low blood calcium on the health and productivity of dairy cows around the time of calving. Information also was shared about a negative dietary cation-anion difference diet as an effective tool to help maintain normal blood calcium concentrations in these animals.
Besides fresh cow health, Bethard's other top 10 keys to a good profit and loss statement include:
1. Keep a full barn. Figure out how many cows can fit in a facility, and strive to maintain that every day.
2. Minimize replacement costs, which is the third-highest cost of producing milk.
3. Realize quality and component premiums, because these premiums boost milk income.
4. Maximize income over feed costs, which is a key margin affected directly by management.
5. Procure high-quality forages. It is hard to have healthy or productive cows with poor-quality forages.
6. Generate pregnancies, because pregnancies generate cow flow and income over feed costs.
7. Cut costs intelligently. Find savings where possible, but not at the expense of health, fresh cows or forage quality.
8. Control labor costs per hundredweight of milk produced.
9. Minimize feed shrink. If feed shrink were itemized, it would be the third- or fourth-highest cost on the average dairy and the second-highest cost for the below-average dairy.
Scientists have discovered a mutation with a built-in dilemma for dairy cattle breeders: a deleted gene sequence that has a positive effect on milk yield but causes embryonic death in dairy cattle.
Scientists have found a genomic deletion that affects fertility and milk yield in dairy cattle at the same time, and the discovery can help explain a dilemma in dairy cattle breeding: the negative correlation between fertility and milk production, according to an announcement from Aarhus University in Denmark.
For many years, milk yield in Scandinavian dairy cattle has been increasing. This has been due to targeted breeding programs and modern breeding methods. Despite having large weight as a breeding goal in Nordic countries, almost no improvement has been achieved for fertility. It now seems that this unfavorable correlation between milk yield and fertility is partially affected by the deletion of a simple gene sequence, Aarhus said.
The presence and effects of this mutation were recently discovered by scientists from Aarhus, the University of Liege and MTT Agrifood Research Finland, in collaboration with the Danish Agricultural Advisory Service and Nordic Cattle Genetic Evaluation.
Scientists, farmers and advisers have generally assumed that the reduction in fertility is primarily due to the negative energy balance of high-producing cows at the peak of their lactation, Aarhus explained, but the scientists have also found a genetic explanation now.
"We have discovered a deletion encompassing four genes as the causative variant and shown that the deletion is a recessive embryonically lethal mutation," explained Goutam Sahana, with the Aarhus department of molecular biology and genetics. "This means that the calves die while they are still embryos and are aborted or reported as insemination failure. The fact that the mutation is recessive means that both parents must carry it and pass the genes on to their calf for the calf to be affected. The bulls carrying the deletion can be routinely identified in ongoing genomic selection program, and by avoiding carrier-by-carrier matings, a quantum jump in fertility could be achieved in Nordic red breeds."
Sahana is a senior scientist with the department's Center for Quantitative Genetics & Genomics.
To make matters worse, this particular mutation has become rather common in Nordic Red cattle, but the deletion is totally absent in Nordic Holstein and Danish Jersey populations. Based on the frequency of the mutation in the population, it is estimated that 2.89%, 1.32% and 0.42% of embryos are dying in Finnish Ayrshire, Swedish Red and Danish Red cattle, respectively, due to this mutation.
The reason the deleted gene sequence that causes embryo mortality has become relatively widespread is that it has such as strong positive effect on milk yield. By selecting for high milk yields, breeders have inadvertently also selected for embryo mortality — a situation of so-called hitchhiking.
"Our study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle and that associated positive effects on milk yield may account for part of the negative genetic correlation. This is at least the seventh example in livestock of an allele that is deleterious in the homozygous state being maintained at high frequency in the populations because of the selective advantage it confers to heterozygotes," Sahana said.
The research was published in PloS Genetics.
The findings echo research reported in 2009 by the U.S. Department of Agriculture's Agricultural Research Service that showed that many of the genes and chromosome regions associated with milk yield were also related to a reduced fertility rate in U.S. Holsteins (Feedstuffs, Oct. 12, 2009).