Water buffalo
The water buffalo, also called domestic water buffalo, Asian water buffalo, and Asiatic water buffalo, is a large bovine originating in the Indian subcontinent and Southeast Asia. Today, it is also kept in Italy, the Balkans, Australia, the Americas, and some African countries. Two extant types of water buffalo are recognized, based on morphological and behavioural criteria: the river buffalo of the Indian subcontinent and further west to the Balkans, Egypt, and Italy; and the swamp buffalo from Assam in the west through Southeast Asia to the Yangtze Valley of China in the east.
The wild water buffalo is most probably the ancestor of the domestic water buffalo. Results of a phylogenetic study indicate that the river-type water buffalo probably originated in western India and was domesticated about 6,300 years ago, whereas the swamp-type originated independently from Mainland Southeast Asia and was domesticated about 3,000 to 7,000 years ago. Subsequently, the river buffalo dispersed west as far as Egypt, the Balkans, and Italy; while swamp buffalo dispersed to the rest of Southeast Asia and up to the Yangtze Valley.
Water buffaloes were traded from the Indus Valley Civilisation to Mesopotamia, in modern Iraq, in 2500 BC by the Meluhhas. The seal of a scribe employed by an Akkadian king shows the sacrifice of water buffaloes.
Water buffaloes are especially suitable for tilling rice fields, and their milk is richer in fat and protein than that of dairy cattle. A large feral population became established in northern Australia in the late 19th century, and there are smaller feral herds in Papua New Guinea, Tunisia, and northeastern Argentina. Feral herds are also present in New Britain, New Ireland, Irian Jaya, Colombia, Guyana, Suriname, Brazil, and Uruguay.
Taxonomy
first described the genus Bos and the water buffalo under the binomial Bos bubalis in 1758; the species was known to occur in Asia and was held as a domestic form in Italy. Ellerman and Morrison-Scott treated the wild and domestic forms of the water buffalo as conspecifics, whereas others treated them as different species. The nomenclatorial treatment of the wild and domestic forms has been inconsistent and varies between authors and even within the works of single authors.In March 2003, the International Commission on Zoological Nomenclature achieved consistency in the naming of the wild and domestic water buffaloes by ruling that the scientific name Bubalus arnee is valid for the wild form. B. bubalis continues to be valid for the domestic form and applies also to feral populations.
In the early 1970s, different names were proposed for the river and swamp types of water buffaloes; the river type was referred to as Bubalus bubalis bubalis, while the swamp type was referred to as Bubalus bubalis carabanensis. However, Bubalus carabanensis is considered a junior synonym of Bubalus kerabau.
Characteristics
The skin of the river buffalo is black, but some specimens may have dark, slate-coloured skin. Swamp buffaloes have grey skin at birth, which becomes slate blue later. Albinoids are present in some populations. River buffaloes have 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, with a short body and large belly. The forehead is flat, the eyes are prominent, the face is short, and the muzzle is 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. The size of the body and shape of the horns may vary greatly among breeds. Height at the withers is for bulls and for cows, but large individuals may attain. Head-lump length at maturity typically ranges from with a long tail. They range in weight from, but weights of over have also been observed.Tedong bonga is a piebald water buffalo with a unique black and white coloration favoured by the Toraja of Sulawesi.
The swamp buffalo has 48 chromosomes, while the river buffalo has 50 chromosomes. The two types do not readily interbreed, but fertile offspring can occur. Water buffalo-cattle hybrids have not been observed to occur, but the embryos of such hybrids reach maturity in laboratory experiments, albeit at lower rates than non-hybrids.
The rumen of the water buffalo differs from the rumen of other ruminants. It contains a larger population of bacteria, particularly the cellulolytic bacteria, lower protozoa, and higher fungi zoospores. In addition, higher levels of the rumen ammonia nitrogen and pH have been found compared to those in cattle.
Ecology and behavior
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. Both are well-adapted to a hot and humid climate with temperatures ranging from in the winter to 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 water buffalo breeds are adapted to saline seaside shores and saline sandy terrain.Diet
Green fodders are widely used for intensive milk production and for fattening. Many fodder crops are conserved as hay, chaffed, or pulped. Fodders include alfalfa, banana plants, cassava, maize, oats, and sorghum. During floods, the animals can graze under water, feeding on aquatic plants such as reeds, sedges, and species of marsh grasses. They can help to keep waterways open by eating water hyacinth.Reproduction
Swamp buffaloes generally become reproductive at an older age than river breeds. Young males in Egypt, India, and Pakistan are first mated around 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 buffalo male can impregnate 100 females in a year. A strong seasonal influence on mating occurs. Heat stress reduces libido.Although water buffaloes are polyoestrous, their reproductive efficiency shows wide variation throughout the year. The cows exhibit a distinct seasonal change in displaying oestrus, conception rate, and calving rate. The age at the first oestrus of heifers varies between breeds from 13 to 33 months, but mating at the first oestrus is often infertile and usually deferred until they are 3 years old. Gestation lasts from 281 to 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. Finding water buffaloes that continue to work well at the age of 30 is not uncommon, and instances of a working life of 40 years have been recorded.
Domestication and breeding
The most probable ancestor of domesticated water buffalo is the wild water buffalo, which is native to the Indian subcontinent and tropical Southeast Asia. Two types of domesticated water buffalo are recognized, based on morphological and behavioural criteria – the river buffalo and the swamp buffalo.River- and swamp-type water buffalo are believed to have been domesticated independently. Results of a phylogenetic study indicate that the river-type water buffalo probably originated in western India and was probably domesticated about 6,300 years ago ; the swamp-type originated independently from Mainland Southeast Asia, being domesticated between 3–7,000 years ago. The river buffalo dispersed west as far as Egypt, southern Europe, the Levant, and the Mediterranean regions; swamp buffalo dispersed in the opposite direction, to the rest of Southeast Asia, and as far as the Yangtze Valley in China.
Swamp-type water buffalo entered Island Southeast Asia from at least 2,500 years ago through the northern Philippines, where butchered remains of domesticated water buffalo have been recovered from the Neolithic Nagsabaran site. These became the ancestors of the distinctly swamp-type carabao buffalo breed of the Philippines which, in turn, spread to Guam, Indonesia, and Malaysia, among other smaller islands.
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. Twenty-two breeds of the river buffalo are known, including the Murrah, Nili-Ravi, Surti, Carabao, Anatolian, Mediterranean, and Egyptian buffaloes. China has a huge variety of water buffalo genetic resources, with 16 local swamp buffalo breeds in various regions.
Genetic studies
analyses indicate that the two types were domesticated independently. Sequencing of cytochrome b genes of Bubalus species implies that the water buffalo originated from at least two populations, and that the river-type and the swamp-type 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 of the northern Philippines.A 2008 DNA analysis of Neolithic water buffalo remains in northern China found that the remains were of the extinct Bubalus mephistopheles and are not genetically related to modern domesticated water buffaloes. Another study in 2004 also concluded that the remains were from wild specimens. Both indicate that water buffaloes were first domesticated outside of China. Analyses of mitochondrial DNA and single-nucleotide polymorphism indicate that swamp and river buffaloes were crossbred in China.
A 2020 analysis of the genomes of 91 swamp and 30 river buffaloes showed that they separated already before domestication about. A 2021 analysis of water buffalo and lowland anoa genomes unexpectedly found the anoa branching somewhere between swamp and river buffaloes. A 2023 Filipino study using the CytB gene instead found the tamaraw branching between the two.