HERD HEALTH CHECK

from December 2021 California Cattleman

Is drought another new normal?

HOW STRESS DUE TO WEATHER AFFECTS YOUR CATTLE AND HORSES

from Pro Earth Animal Health

Keeping your livestock healthy throughout the year allows your animals to be productive and avoid diseases. Unfortunately, weather conditions can present an obstacle to livestock’s health and well-being. But how exactly do weather changes and fluctuations affect the stress levels of your cattle and horses? What can changes in weather and stress levels mean for your livestock?

To keep your livestock thriving, it’s important to understand how exactly the weather impacts their stress levels and what you can do to help ease the effects of difficult weather conditions.

Body Temperature Regulation: Cattle and Horses

Livestock can regulate their body temperatures like humans, but only so much. The regulation of body temperature is known as thermoregulation. The body uses thermoregulation to avoid cold or heat stress. Because thermoregulation is limited, it’s important to note the weather changes that can impact the body temperature of your livestock. 1. Thermoregulation in Cattle

The body temperature of cattle is affected by their body condition, diet, conditions of their shelter and the thickness of their hair coat. Weather factors, such as wind and humidity, can also influence cattle’s body temperature.

Cattle hair coats vary by breed in terms of color and thickness. The hair coat also affects their ability to release heat through their skin. In a warmer region, cattle with a thick hair coat may be more susceptible to heat stress. Cattle with a thinner hair coat are more likely to be tolerant of higher temperatures in warm regions. Alternatively, cattle with a thinner hair coat may become more stressed in a colder environment.

Cattle body temperature can fall into three zones –– thermoneutral, upper critical (UCT) and lower critical temperature (LCT) zone. At the basal metabolic rate, cattle will be in the thermoneutral zone. So what exactly is the basal metabolic rate? It’s the amount of energy that is expended while cattle are at rest in neutral temperatures.

Neutral temperatures typically fall between 31 to 68 degrees Fahrenheit, though this range can vary depending on the breed of cattle and the conditions of their environment. Wind, humidity and cattle hair coat all affect the temperature range that is considered neutral for cattle.

Upper critical temperatures are above the thermoneutral zone and increase the basal metabolic rate. The increased basal metabolic rate results in the body stimulating heat loss to maintain body temperature. When the temperature-humidity index is 80 or above, livestock may suffer from heat stress. Cattle produce little sweat and are not able to dissipate their heat efficiently, so producers often need to take steps to assist cattle with heat dissipation.

Cattle most often fall into the lower critical temperature zone during especially cold months, such as January and February. In LCT, cattle can experience cold stress. The basal metabolic rate increases to produce heat that can maintain or raise body temperature. This means the animal also requires more energy so it can produce heat. Beware of extreme cold stress, which can result in hypothermia. 2. Thermoregulation in Horses

Like cattle, thermoregulation in horses allows these animals to maintain, raise or lower body temperature. Unlike cattle, however, horses are more efficient at discharging heat in hot weather. Despite this, owners should still take measures to help their horses stay cool during hot, humid months. Horses use the following methods to maintain body temperature:

Evaporation of sweat: A horse will produce sweat that then evaporates, cooling the animal down. In a humid climate, sweat may not be able to evaporate, preventing the horse from adequately cooling. Owners can assist with creating a less humid environment for their horses so that evaporation of sweat can occur.

Convection: In this process, heat moves from inside the horse out into the air. Air movement and wind carry heat away from horses. To assist your horses further,

especially if there isn’t much wind on a hot, humid day, a fan can be implemented to help move the air.

Direct radiation: Radiant heat comes directly off the horse and isn’t effective when the horse is standing in the sun. Providing them with shade can make the radiant cooling process more effective.

Conduction: Conduction is similar to convection, except that the heat that has built up in the horse’s blood is transferred to the air. On days when the air temperature is especially high, conduction isn’t very effective.

Respiratory loss: Horses can also lose a small amount of heat when they exhale.

To determine whether it is too hot to work your horse, calculate the heat index. Add the temperature in Fahrenheit plus the percent of humidity. The sum is the heat index. If the heat index is less than 120, it is safer to work them. If the heat index is between 120 and 150, use caution when riding or exercising your horse. If the heat index is more than 150, it is important to avoid working them until the heat index has dropped. 10 Signs of Weather Stress in Livestock

How much cold can cows tolerate and how much cold can horses tolerate before they experience weather stress? To keep livestock healthy and productive, you should be aware of the signs of stress. Knowing what to look for means you can improve your livestock’s conditions when the weather is posing extremes that can be detrimental to their health.

Reduced milk production. During hot weather, dairy cows may experience reduced milk production due to stress. Feed intake drops in dairy cattle when temperatures rise, causing milk production to also drop. This decrease in milk production can have a major negative impact on the prosperity of the dairy business, so you’ll want to relieve your cows of weather stress as quickly as possible to ensure continued productivity.

Changes in feed and water intake. In hot weather, cattle may consume less feed. Reduced feed intake can cause ruminal acidosis and decrease the animal’s production of volatile fatty acids. This, in turn, reduces the cow’s energy levels and fat content in its milk. In the heat, cattle and horses may also drink more water to stay hydrated and cool.

Reduced conception rate. Calving alone puts stress on a cow. Combine the stress from calving with weather stress? Lowered fertility and fewer calves.

Rapid respiration rate. Extreme cold weather can result in cold stress. Young animals are particularly susceptible to respiratory issues in cold weather conditions. Horses may also pant when they are dealing with heat stress, so if you are noticing rapid respiration in your cattle or horses, they may be experiencing weather stress.

Standing when other cattle are lying down. When a cow is behaving differently from the other cattle, it’s a sign that something is wrong. A cow that stands while the others are lying down could be experiencing weather stress.

Weight loss. Stressed cattle and horses may also experience weight loss due to a lack of appetite. The weight loss may negatively affect an animal’s ability to stay warm and productive in cold weather.

Frequent urination. Cattle and horses may also urinate more frequently when experiencing weather stress. Animals may urinate frequently to relieve stress or because of increased intake of water. Horses may also produce a greater amount of manure or experience diarrhea.

Weakened immune system. Cold stress, especially prolonged cold stress, can increase the cortisol levels in a cow or horse and weaken the animal’s immune system. Stressed animals are more likely to become ill by contracting infectious diseases. Since diseases may spread quickly to other livestock, this can become a major problem for producers.

Frequent yawning. In horses, frequent yawning may be a sign of stress. Yawning releases endorphins, so frequent yawning could be a coping mechanism for your horse as it combats stress.

Rapid heart rate and excessive sweating. If you notice a rapid heart rate in your cow or horse, the animal may be suffering from heat stress. Trembling is a similar sign of weather stress that may appear in cattle and horses, especially if they are trembling in an ordinary situation without a stressful trigger, such as transportation or a visit from the veterinarian. Heat stress may also cause horses to sweat excessively. ASSIST PREGNANT CATTLE

Pregnant cattle should be carefully monitored through the winter. Check with your veterinarian about any specific vaccinations they may need to keep them healthy through the winter, including nutritional supplements and deworming.

Pay special attention to them through harsh weather, too. They need to be shielded from extreme temperatures and they have easy access to food and water, regardless of how deep the snow is. Remember a healthy, well-fed mother is going to pay big dividends later on.

In fact, segregating pregnant cows into paddocks for close monitoring is always helpful. Doing so allows you to provide them with the right nutrition, water and shelter. Also, it keeps them close as they approach their due date. That allows you to be on scene and properly equipped to help during delivery. KEEP CATTLE COMFORTABLE

Beyond all the efforts listed above, there are additional ways to bring comfort to your cattle, winter time or not.

Providing sand beds for resting cows helps ease stress on knees and hocks. Some ranchers have gone a step beyond sand beds, installing sloped water beds to ease body stress and increase comfort.

Bedding material is also helpful, especially if cows are wet and its cold out.

Another simple solution to increase comfort is to give your cows space – such as extra bed spaces and spaces for feeding. By keeping your herd size at the appropriate level for your capacity, your cattle will be far less stressed and produce better for you.

NCBA Urges Vilsack to Halt Brazilian Beef Imports citing safety concerns, threats to consumers

On November 12, the National Cattlemen's Beef Association (NCBA) called on U.S. Department of Agriculture Secretary Tom Vilsack to immediately suspend all imports of fresh beef from Brazil to the United States.

In the letter to the USDA, NCBA asked for a suspension until the agency conducts a thorough risk assessment and review of the processes that Brazil's Ministry of Agriculture, Livestock and Food Supply (MAPA) uses to detect disease and other threats to consumers. NCBA also urged USDA to review Brazil's veterinary diagnostic laboratory system.

The request follows two incidents of atypical bovine spongiform encephalopathy (BSE) in Brazil this summer which the nation failed to disclose to the World Organization for Animal Health (OIE) for at least ten weeks. Atypical BSE cases identified on June 11 and June 25 were not reported to OIE until September 3. "It's time to keep Brazilian fresh beef out of this country until USDA can confirm that Brazil meets the same consumer and food safety standards that we apply to all our trade partners," said NCBA Vice President of Government Affairs Ethan Lane. "NCBA has long expressed concerns about Brazil's history of failing to report atypical BSE cases in a timely manner, a pattern that stretches back as far as 2012. Their poor track record and lack of transparency raises serious doubts about Brazil's ability to produce cattle and beef at an equivalent level of safety as American producers. If they cannot meet that bar, their product has no place here," added Lane.

According to reports published by the World Organization for Animal Health (OIE), Brazil took more than eight weeks to report two confirmed cases of atypical bovine spongiform encephalopathy (BSE). The OIE requires countries to report within 24 hours for any animal disease event that could be of international concern for public health emergencies.

After the market devastation of 2003, American cattle producers have worked diligently to protect consumers and restore confidence both at home and abroad. Farmers and ranchers benefit greatly from the demand for beef that is built upon a commitment to integrity, transparency and the highest scientific standards.

The consumer trust that our producers have worked so hard to build must not be jeopardized by any country that seeks to cut corners or conceal the truth about food safety concerns. Brazilian beef companies must prove that they are worthy of access to American consumers.