Capra hircus Linnaeus, 1758

Species Naming

The domestic goat (Capra hircus Linnaeus, 1758) has distinct size variation across breeds.

Weight Range

Adult weight ranges from over 140 kg (310 lb) for males (bucks) of large breeds like the Boer, down to 20 to 27 kg (44 to 60 lb) for females (does) of smaller breeds.

Within-Breed Size Variation

Different strains or bloodlines within the same breed can also have different recognized standard sizes.

Miniature Breed Size

At the smallest end of the size range are miniature breeds such as the African Pygmy, where adult individuals stand 41 to 58 cm (16 to 23 in) at the shoulder.

Horn Prevalence

Most goats naturally have two horns, with shape and size varying by breed.

Polycerate Trait

While rare genetic occurrences of polycerate goats (with up to eight horns) have been recorded, this trait is very uncommon.

Polled Breeding Challenges

Unlike cattle, goats have not been successfully bred to be reliably polled (naturally hornless), because the genes that determine sex and the genes that determine horn presence are closely linked.

Intersex Offspring Risk

Breeding two genetically polled goats produces a high number of intersex offspring, which are typically sterile.

Horn Composition and Function

Goat horns are made of living bone covered by keratin and other proteins, and are used for defense, establishing dominance, marking territory, and thermoregulation.

Facial Skin Appendages

Both male and female goats can have beards, and many goat types (most commonly dairy goats, dairy-cross Boers, and pygmy goats) can have wattles, with one wattle dangling from each side of the neck.

Pupil Shape

Goats have horizontal, slit-shaped pupils.

Pupil Function

This pupil shape lets them see well in both night and day, gives them a wide field of vision to detect predators on either side, and prevents them from being dazzled by overhead sunlight.

Tear Duct Absence

Goats do not have tear ducts.

Digestive System Structure

Goats are ruminant even-toed ungulates, with a four-chambered stomach made up of the rumen, reticulum, omasum, and abomasum.

Udder and Teat Structure

Female goats have an udder with two teats, which differs from cattle that have four teats.

Boer Goat Teat Exception

The Boer goat is an exception, as it can sometimes have up to eight teats.

Karyotype

Goats are diploid, with two sets of 30 chromosomes.

Agility and Curiosity

Goats are naturally curious and agile, able to climb and balance in precarious locations.

Tree Climbing Trait

They are the only ruminant that regularly climbs trees.

Enclosure Escape Behavior

These traits make them notorious for escaping enclosures, as they constantly test fences; goats almost always escape if a fence can be overcome.

Cognitive Ability

Some studies have found goats to be as intelligent as dogs.

Herding Behavior

When grouped together, goats show less herding behavior than sheep.

Grazing Pattern

When grazing undisturbed, they spread out across a field or range, rather than feeding side by side like sheep do.

Young Rearing Behavior

When nursing their young, goats leave their kids separated (a behavior called "lying out") rather than grouped together, as sheep do.

Intruder Response

Goats generally turn and face an intruder, and bucks are more likely to charge or butt humans than male sheep (rams) are.

Human Communication Trait

A 2016 study found that goats attempt to communicate with people in the same way as other domesticated animals like dogs and horses, and will look to a human for help when faced with a new, modified challenge.

Puberty Timing

Goats reach puberty between three and 15 months of age, depending on breed and nutritional status.

Breeding Age Recommendation

Many breeders prefer to delay breeding until a doe reaches 70% of her adult weight, but this schedule is rarely possible in extensively managed open-range herds.

Temperate Breed Breeding Season

For Swiss and northern breeds, uncastrated males (bucks) enter rut (breeding season) in the fall, matching the females' fall heat cycles.

Equatorial Breed Breeding Pattern

Bucks of equatorial breeds may have seasonal reduced fertility, but like does they are able to breed at any time of year.

Rut Behavior Traits

Rut is defined by decreased appetite and obsessive focus on does.

Rut Display Behaviors

A buck in rut performs flehmen lip curling, and urinates on his forelegs and face.

Buck Scent Gland Function

Sebaceous scent glands at the base of the buck's horns contribute to his odor, which is important for attracting females; some does will not mate with a buck that has had its scent glands removed.

Gestation Length

Goat gestation is approximately 150 days long.

Litter Size Frequency

Twins are the most common birth outcome, with single and triplet births also common.

Uncommon Litter Sizes

Larger litters of four, five, or even six kids occur less frequently.

Kidding Process

Goat birth is called kidding, and it generally proceeds without complications.

Pre-Kidding Physical Signs

Just before kidding, a doe will develop a sunken area around her tail and hip, and breathe heavily.

Pre-Kidding Behavioral Signs

She may look anxious, become restless, and show increased affection for her keeper.

Placenta Consumption Behavior

Goat mothers often eat the placenta after birth, which provides much-needed nutrients, helps stop bleeding, and follows the same behavior seen in wild herbivores like deer that reduces the chance predators are attracted by birth scent.

Freshening Timing

Freshening, when a doe begins milk production, usually happens at kidding, though it is also relatively common for unbred dairy doelings to produce milk.

Milk Production Variables

Milk production varies based on a doe's breed, age, overall quality, and diet.

Annual Dairy Goat Milk Yield

Dairy goats generally produce between 680 and 1,810 kg (1,500 and 4,000 lb) of milk over a 305-day lactation period.

Average Daily Milk Yield

On average, a good quality dairy doe produces at least 3 kg (6 lb) of milk per day while she is lactating.

Milk Yield Variations

First-time milkers may produce less, though exceptional individuals can produce as much as 7 kg (16 lb) or more.

Lactation Cessation

After lactation, the doe will "dry off" (stop producing milk), typically after she has been bred again.

Extended Lactation Occurrence

Occasionally, unbred goats that are continuously milked will continue lactating beyond the typical 305-day period.

Male Lactation

Male lactation sometimes occurs in goats.

Agricultural Uses

Goats are used to produce milk, specialty wools, meat, and goatskin.

International Poverty Alleviation Use

Some charities give goats to impoverished people in low-income countries, based on the idea that providing useful productive assets alleviates poverty more effectively than cash.

Goat Distribution Cost

However, the total cost of obtaining and distributing goats can be high.

Military Medical Training Use

Some national militaries use goats to train combat medics.

US Military Training History

In the United States, goats became the main animal species used for this purpose after the Pentagon stopped using dogs for medical training in the 1980s.

Live Training Rationale

Though modern training mannequins effectively simulate human body function, trainees report that working with live goats creates a sense of urgency that only real-life trauma can provide.

Training Practice Controversy

This practice has sparked strong public outcry from animal-rights groups.