Behavioral Problems of Cattle
Most behavioral problems in cattle involve breeding or aggression and are related to poor management practices, confinement, and lack of enrichment.
Silent heat occurs most often in heifers during the first cycle. Physical signs of heat (eg, vaginal discharge, vulvar relaxation, and behavioral signs) are absent. Estrus detection methods (see Social Behavior of Cattle) can help identify cows in heat. In recent years, the use of freemartins and dogs for detection of estrus has gained popularity.
Increased sexual behavior occurs mainly in high-producing dairy cows that are 4–6 yr old and have had 1–3 calves. These cows usually mount other cows excessively, act like bulls, and have a significant decrease in milk production. In most cases nymphomania is associated with follicular cysts, and treatment with luteinizing hormone or chorionic gonadotropin is useful.
Masturbation in bulls normally does not affect fertility. The bull will have a partial erection, arch its back, and perform pelvic thrusts. Because this does not lead to increased aggression or reduced fertility, no treatment is needed. Increases in exercise and stimulation can reduce the frequency.
Many diseases of bulls can lead to poor libido; therefore, the first step in managing impotence is excluding and treating possible diseases. Bulls with poor libido may refuse to mount, avoid estrous cows, and be unable to develop an erection. Behavioral causes for impotence include inexperience in young bulls that attempt breeding an aggressive cow, bulls that are used too frequently for semen collection, and the stress of a new environment. Using a new teaser bull or, preferably, a teaser cow in estrus can stimulate these bulls to breed. Allowing the bull to watch other bulls mounting may increase arousal. Food rewards (eg, molasses) may help as well. In many cases impotent bulls should be eliminated from breeding programs, or alternative ways of semen collection such as electroejaculation should be used.
Buller steers are steers mounted by others. This problem is seen in ~3% of feedlot steers and seems related to both hormonal and crowding factors. Steers are usually implanted with anabolic steroids, most commonly stilbesterol or estrogen, which can lead them to mount others. However, the level of these hormones in the buller is usually lower. In large, overcrowded groups of steers, the number of bullers is higher. This problem may also be related to dominance; the more dominant and aggressive steers mount others. Erection and intromission rarely occur. Both the buller and the mounting steer may fail to gain adequate weight because of psychological stress and increased activity. Removing the buller is the most common solution. Adding hiding places, placing overhead electric wires, providing sufficient food and water to avoid conflict, and painting odiferous material on the back of the buller also can help reduce incidence of this behavior.
Aggression in cattle is usually a result of fear, learning, and hormonal state. Aggression between cows is worse than that between bulls. Horned cattle will bunt (push or strike with the horns) and strike an opponent on the side. Polled cows will use their head as a battering ram. Two cows can fight for a long period with resting periods in between. Each cow will rest while pushing its muzzle between the udder and hindquarter of the other cow to immobilize it. Aggression toward people usually includes bunting, kicking, and crushing. Aggressive and dangerous animals should be culled.
Bulls are notorious for their unpredictable aggression. Some bulls may mount others, and these may respond with aggression. Such fights can end with serious injuries and even death, especially if the bulls are horned. Dairy bulls are commonly more aggressive (and also larger and heavier) than beef bulls. The bull may paw and dig in the ground, and horned bulls may kneel on the front legs and dig using their horns. Because hand-reared bulls are more aggressive toward other bulls, it is thought that inadequate socialization may contribute to this behavior. Aggressive bulls should be separated from others and perhaps culled if dangerous to people.
Kicking is mainly a problem in beef cattle and is seen most commonly in heifers. Beef cattle are not selectively bred for gentleness and are handled minimally. These animals can be dangerous when placed in pens or cages for examination and may cause severe injuries. Such animals should be handled carefully and potentially sedated. Food rewards can be offered for calm behaviors.
Non-nutritional suckling is a common problem in calves; the suckling calf will suck on other calves or the cow on any available appendage or skin tag. This can lead to skin irritation and even umbilical hernias (if the suckling calf suckles on the umbilical sheath of another calf). Poor nutrition may influence development of this behavior (increasing roughage can minimize the problem). Penning or isolating suckling calves does not solve the problem; the calf will continue to suckle on buckets or engage in self-suckling. The problem is more common in calves weaned after 6 days of age. Non-nutritional suckling occurs mostly after feeding; providing dry teats next to the feeding area can help reduce incidence of this behavior. Other ways to minimize this behavior include placing a serrated nose ring in the suckling calf, applying repellent materials to suckled areas, and fitting a muzzle. These may prevent suckling but do not reduce the motivation to do so, and calf welfare should be considered.
In some cases, it is necessary to cross-foster a calf. Dairy cows are more likely to refuse a new or unfamiliar calf than beef cows. Bonding between the cow and calf is based on fetal fluid and visual cues; therefore, covering the new calf with drapes soaked with amniotic fluid or the skin of the cow’s own dead calf or blindfolding the cow can help. Encouraging the cow with food rewards can also help.
Reluctance to enter the milking parlor is a problem related mainly to management. When dairy cows accustomed to milking with simultaneous feeding in a stanchion barn are moved to free stalls and are not fed when milked, they may refuse to enter the parlor. Previous negative experience (eg, mastitis, aberrant electric shock, punishment from the handler) can also play a role. In addition, changing the side from which the cow is normally milked can increase anxiety and even aggression. Providing more grain feeding, a calm environment, and possibly a preferred cow “mate” can help minimize the problem. Similar problems can arise with the introduction of electric squeeze gates.
The underlying cause of food throwing is not well understood. The affected animal grabs food with its mouth and throws it on its back. One possible explanation is maintenance behavior that is meant to reduce biting flies in the presence of docked tails. The diet mixture may also play a role; the problem is seen more commonly in cattle fed a total mixed ration.
Tongue rolling occurs mainly in veal cattle and is most likely a stereotypic behavior resulting from confinement. The affected calf flicks its tongue outside and rolls it back inside the mouth, followed by swallowing saliva. One study showed that veal calves that displayed tongue rolling had no abomasal ulcers, while those that did not show this behavior had ulcers. This may indicate that the behavior reduces stress. However, calves that showed tongue rolling as well as those that did not had abomasal erosions. Increasing stimulation (eg, adding sucking teats) may reduce incidence of this behavior.