AppearanceCattle have one stomach with four compartments. They are the rumen, reticulum, omasum, and abomasum, with the rumen being the largest compartment. The reticulum, the smallest compartment, is known as the "honeycomb". Cattle sometimes consume metal objects which are deposited in the reticulum and irritation from the metal objects causes hardware disease. The omasum's main function is to absorb water and nutrients from the digestible feed. The omasum is known as the "many plies". The abomasum is like the human stomach; this is why it is known as the "true stomach".
Cattle are ruminants, meaning that they have a digestive system that allows use of otherwise indigestible foods by regurgitating and rechewing them as "cud". The cud is then reswallowed and further digested by specialised microorganisms in the rumen. These microbes are primarily responsible for decomposing cellulose and other carbohydrates into volatile fatty acids that cattle use as their primary metabolic fuel. The microbes inside the rumen are also able to synthesize amino acids from non-protein nitrogenous sources, such as urea and ammonia. As these microbes reproduce in the rumen, older generations die and their carcasses continue on through the digestive tract. These carcasses are then partially digested by the cattle, allowing them to gain a high quality protein source. These features allow cattle to thrive on grasses and other vegetation.
The gestation period for a cow is nine months. A newborn calf weighs 25 to 45 kilograms . The world record for the heaviest bull was 1,740 kilograms , a Chianina named Donetto, when he was exhibited at the Arezzo show in 1955. The heaviest steer was eight year old ‘Old Ben’, a Shorthorn/Hereford cross weighing in at 2,140 kilograms in 1910. Steers are generally killed before reaching 750 kilograms . Breeding stock usually live to about 15 years . The oldest recorded cow, Big Bertha, died at the age of 48 in 1993.
A common misconception about cattle is that they are enraged by the color red . This is incorrect, as cattle are red-green color-blind. The myth arose from the use of red capes in the sport of bullfighting; in fact, two different capes are used. The capote is a large, flowing cape that is magenta and yellow. The more famous muleta is the smaller, red cape, used exclusively for the final, fatal segment of the fight. It is not the color of the cape that angers the bull, but rather the movement of the fabric that irritates the bull and incites it to charge.
Having two kinds of color receptors in the cone cells in their retinas, cattle are dichromatic, as are most other non-primate land mammals.
A cow's udder contains 2 pairs of mammary glands.
NamingCattle were originally identified as three separate species: ''Bos taurus'', the European or "taurine" cattle ; ''Bos indicus'', the zebu; and the extinct ''Bos primigenius'', the aurochs. The aurochs is ancestral to both zebu and taurine cattle. Recently these three have increasingly been grouped as one species, with ''Bos primigenius taurus'', ''Bos primigenius indicus'' and ''Bos primigenius primigenius'' as the subspecies.
Complicating the matter is the ability of cattle to interbreed with other closely related species. Hybrid individuals and even breeds exist, not only between taurine cattle and zebu but also between one or both of these and some other members of the genus ''Bos'' – yaks , banteng, and gaur. Hybrids such as the beefalo breed can even occur between taurine cattle and either species of bison, leading some authors to consider them part of the genus ''Bos'' as well. The hybrid origin of some types may not be obvious – for example, genetic testing of the Dwarf Lulu breed, the only taurine-type cattle in Nepal, found them to be a mix of taurine cattle, zebu, and yak. However, cattle cannot successfully be hybridized with more distantly related bovines such as water buffalo or African buffalo.
The aurochs originally ranged throughout Europe, North Africa, and much of Asia. In historical times its range became restricted to Europe, and the last known individual died in Masovia, Poland, in about 1627. Breeders have attempted to recreate cattle of similar appearance to aurochs by crossing traditional types of domesticated cattle, creating the Heck cattle breed.
DistributionThe world cattle population is estimated to be about 1.3 billion.
The following table shows the cattle population in 2009
Africa has about 20,000,000 head of cattle, many of which are raised in traditional ways and serve partly as tokens of their owner's wealth.
HabitatA report from the Food and Agriculture Organization states that the livestock sector is "responsible for 18% of greenhouse gas emissions". The report concludes that, unless changes are made, the damage thought to be linked to livestock may more than double by 2050, as demand for meat increases. One of the cited changes suggested is intensification of the livestock industry, since intensification leads to less land for a given level of production. Practices prevailing in 2007 involved 8.6 percent less fossil fuel use, 16.3 percent less greenhouse gas emissions, 12.1 percent less water use and 33.0 percent less land use than in 1977.
However, there are negative impacts to concentrated animal feeding operations as well, notably contaminated water due to feedlot runoff, soil erosion, human and animal exposure to toxic chemicals, development of antibiotic resistant bacteria and an increase in ''E. coli'' contamination. Some of these impacts can be mitigated by developing wastewater treatment systemsref name=Koelsch/> and planting cover crops in larger setback zones. However, the Union of Concerned Scientists released a report in 2008 concluding that CAFOs are generally unsustainable and externalize costs.
Grazing by cattle at low intensities can create a favourable environment for native herbs and forbs; however, in many world regions cattle are reducing biodiversity due to overgrazing. A survey of refuge managers on 123 National Wildlife Refuges in the US tallied 86 species of wildlife considered positively affected and 82 considered negatively affected by refuge cattle grazing or haying. Proper management of pastures, notably managed intensive rotational grazing and grazing at low intensities can lead to less use of fossil fuel energy, increased recapture of carbon dioxide, fewer ammonia emissions into the atmosphere, reduced soil erosion, better air quality and less water pollution.
Some microbes in the cattle gut carry out anaerobic process known as methanogenesis, which produces methane. Cattle and other livestock emit about 80 to 93 Tg of methane per year,, accounting for an estimated 37 percent of anthropogenic methane emissions, and additional methane is produced by anaerobic fermentation of manure in manure lagoons and other manure storage structures. The 100-year global warming potential of methane, including effects on ozone and stratospheric water vapor, is 25 times as great as that of carbon dioxide. Methane's effect on global warming is correlated with changes in atmospheric methane content. However, the net change in atmospheric methane content was recently about 1 Tg per year,IPCC. 2007. Fourth Assessment Report. Intergovernmental Panel on Climate Change. and in some recent years there has been no increase in atmospheric methane content. Mitigation options for reducing methane emission from ruminant enteric fermentation include genetic selection, immunization, rumen defaunation, diet modification and grazing management, among others. While cattle fed forage actually produce more methane than grain-fed cattle, the increase may be offset by the increased carbon recapture of pastures, which recapture three times the CO2 of cropland used for grain.
If not well managed, manure can have adverse environmental consequences; however, manure also is a valuable source of nutrients and organic matter when used as a fertilizer. Manure was used as a fertilizer on about 15.8 million acres of US cropland in 2006, with manure from cattle accounting for nearly 70 percent of manure applications to soybeans and about 80 percent or more of manure applications to corn, wheat, barley, oats and sorghum. Substitution of manure for synthetic fertilizers in crop production can be environmentally significant, as between 43 and 88 MJ of fossil fuel energy are used per kg of nitrogen in manufacture of synthetic nitrogenous fertilizers.
Some text fragments are auto parsed from Wikipedia.