The water buffalo or domestic Asian water buffalo (Bubalus bubalis) is a large bovid originating in South Asia, Southeast Asia, and China. Today, it is also found in Europe, Australia, and some American countries.[1] The wild water buffalo (Bubalus arnee) native to Southeast Asia is considered a different species, but most likely represents the ancestor of the domestic water buffalo.[2]
Two extant types of water buffalo are recognized based on morphological and behavioural criteria – the river buffalo of South Asia and further west to the Balkans, Egypt, and Italy, and the swamp buffalo, found from Assam in the west through Southeast Asia to the Yangtze valley of China in the east.[1][3] The origins of the domestic water buffalo types are debated, although results of a phylogenetic study indicate that the swamp type may have originated in China and was domesticated about 4,000 years ago, while the river type may have originated from India and was domesticated about 5,000 years ago.[4] Water buffaloes were traded from the Indus Valley Civilisation, in modern Pakistan, to Mesopotamia, in modern Iraq, 2500 BC by the Meluhhas.[5] The seal of a scribe employed by an Akkadian king shows the sacrifice of water buffaloes.[6]
Water buffaloes are especially suitable for tilling rice fields, and their milk is richer in fat and protein than that of dairy cattle. The large feral population of northern Australia became established in the late 19th century, and smaller feral herds are in New Guinea, Tunisia, and northeastern Argentina.[1] There are at least 130 million domestic water buffalo, and more human beings depend on them than on any other domestic animal.[7]
The skin of river buffaloes is black, but some specimens may have dark slate-coloured skin. Swamp buffaloes have a grey skin at birth, but become slate blue later. Albinoids are present in some populations. River buffaloes have comparatively longer faces, smaller girths, and bigger limbs than swamp buffaloes. Their dorsal ridges extend further back and taper off more gradually. Their horns grow downward and backward, then curve upward in a spiral. Swamp buffaloes are heavy-bodied and stockily built; the body is short and the belly large. The forehead is flat, the eyes prominent, the face short, and the muzzle wide. The neck is comparatively long, and the withers and croup are prominent. A dorsal ridge extends backward and ends abruptly just before the end of the chest. Their horns grow outward, and curve in a semicircle, but always remain more or less on the plane of the forehead. The tail is short, reaching only to the hocks. Height at withers is 129–133 cm (51–52 in) for males, and 120–127 cm (47–50 in) for females. They range in weight from 300–550 kg (660–1,210 lb), but weights of over 1,000 kg (2,200 lb) have also been observed.[1]
Tedong bonga is a black pied buffalo featuring a unique black and white colouration that is favoured by the Toraja of Sulawesi.[8]
The swamp buffalo has 48 chromosomes; the river buffalo has 50 chromosomes. The two types do not readily interbreed, but fertile offspring can occur. Buffalo-cattle hybrids have not been observed to occur, and the embryos of such hybrids do not reach maturity in laboratory experiments.[9]
The rumen of the water buffalo has important differences from that of other ruminants.[10] It contains a larger population of bacteria, particularly the cellulolytic bacteria, lower protozoa, and higher fungi zoospores. In addition, higher rumen ammonia nitrogen (NH4-N) and higher pH have been found as compared to those in cattle.[11]
Ecology and behavior[edit]
Water buffalo enjoy being in water.
Water buffalo wallowing in mud
River buffaloes prefer deep water. Swamp buffaloes prefer to wallow in mudholes which they make with their horns. During wallowing, they acquire a thick coating of mud.[1] Both are well adapted to a hot and humid climate with temperatures ranging from 0 °C (32 °F) in the winter to 30 °C (86 °F) and greater in the summer. Water availability is important in hot climates since they need wallows, rivers, or splashing water to assist in thermoregulation. Some breeds are adapted to saline seaside shores and saline sandy terrain.[12]
Diet[edit]
Water buffaloes thrive on many aquatic plants and during floods, will graze submerged, raising their heads above the water and carrying quantities of edible plants. They eat reeds (quassab), a giant reed (birdi), a kind of bulrush (kaulan), water hyacinth, and marsh grasses. Some of these plants are of great value to local peoples. Others, such as water hyacinth, are a major problem in some tropical valleys, and water buffaloes may help to keep waterways clear.
Green fodders are used widely for intensive milk production and for fattening. Many fodder crops are conserved as hay, chaffed, or pulped. Fodders include alfalfa, berseem and bancheri, the leaves, stems or trimmings of banana, cassava, fodder beet, halfa, ipil-ipil and kenaf, maize, oats, pandarus, peanut, sorghum, soybean, sugarcane, bagasse, and turnips. Citrus pulp and pineapple wastes have been fed safely to buffaloes. In Egypt, whole sun-dried dates are fed to milk-buffaloes up to 25% of the standard feed mixture.[1]
Reproduction[edit]
A water buffalo calf in India
Swamp buffaloes generally become reproductive at an older age than river breeds. Young males in Egypt, India, and Pakistan are first mated at about 3.0–3.5 years of age, but in Italy they may be used as early as 2 years of age. Successful mating behaviour may continue until the animal is 12 years or even older. A good river male can impregnate 100 females in a year. A strong seasonal influence on mating occurs. Heat stress reduces libido.[1]
Although buffaloes are polyoestrous, their reproductive efficiency shows wide variation throughout the year. Buffalo cows exhibit a distinct seasonal change in displaying oestrus, conception rate, and calving rate.[13] The age at first oestrus of heifers varies between breeds from 13–33 months, but mating at the first oestrus is often infertile and usually deferred until they are 3 years old. Gestation lasts from 281–334 days, but most reports give a range between 300 and 320 days. Swamp buffaloes carry their calves for one or two weeks longer than river buffaloes. It is not rare to find buffaloes that continue to work well at the age of 30, and instances of a working life of 40 years are recorded.[1]
Taxonomic history[edit]
Carl Linnaeus first described the genus Bos and the water buffalo under the binomial Bubalis bubalus in 1758; the latter was known to occur in Asia and as a domestic form in Italy.[14] Ellerman and Morrison-Scott treated the wild and domestic forms of the water buffalo as conspecifics[15] whereas others treated them as different species.[16] The nomenclatorial treatment of wild and domestic forms has been inconsistent and varies between authors and even within the works of single authors.[17]
In March 2003, the International Commission on Zoological Nomenclature achieved consistency in the naming of wild and domestic water buffaloes by ruling that the scientific name Bubalus arnee is valid for the wild form.[18] Bubalus bubalis continues to be valid for the domestic form and applies also to feral populations.[19]
Domestication and breeding[edit]
Murrah buffaloes at the Philippine Carabao Center
Water buffaloes were domesticated in India about 5000 years ago, and in China about 4000 years ago. Two types are recognized, based on morphological and behavioural criteria – the river buffalo of the Indian subcontinent and further west to the Balkans and Italy, and the swamp buffalo, found from Assam in the west through Southeast Asia to the Yangtze valley of China in the east.[3] The present day river buffalo is the result of complex domestication processes involving more than one maternal lineage and a significant maternal gene flow from wild populations after the initial domestication events.[20] Twenty-two breeds of the river type water buffalo are known, including Murrah, Nili-Ravi, Surti, Jafarabadi, Anatolian, Mediterranean, and Egyptian buffalo.[21] China has a huge variety of buffalo genetic resources, comprising 16 local swamp buffalo breeds in various regions.[12]
Results of mitochondrial DNA analyses indicate that the two types were domesticated independently.[22] Sequencing of cytochrome b genes of Bubalus species implies that the domestic buffalo originated from at least two populations, and that the river and the swamp types have differentiated at the full species level. The genetic distance between the two types is so large that a divergence time of about 1.7 million years has been suggested. The swamp type was noticed to have the closest relationship with the tamaraw.[23]
en.wikipedia.org/wiki/Water_buffalo
