Abstract: In contrast to the great similarity in behaviour and ecology of the 6 extant Equid species, 2 distinct types of social organisation have evolved, and both are adapted to life in semi-arid to arid regions where environmental conditions force them to migrate seasonally or opportunistically.
The ranges of the various species overlap: Mountain Zebra Equus zebra and Plains Zebra E. quagga in South Africa and Namibia, Plains Zebra and Grevy's Zebra E. grevyi in Kenya and Ethiopia, Grevy's Zebra and African Wild Ass E. africanus in Ethiopia, Asiatic Wild Ass E. hemionus and Przewalski Horse E. przewalski in Mongolia and China. Although, in the overlap zones, individuals of the different species are using the same resources like water and grazing next to each other, they rarely make closer contacts.
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In the type 1 species, Horse, Plains Zebra and Mountain Zebra, the adults live in non-territorial, stable, one-male families and as single bachelors and in bachelor groups. Family stallions have the exclusive mating rights with the mares in their harems. These consist of up to 6 unrelated mares plus their offspring, totalling up to 20 members.
Mares stay in their harem until death. Stallions' tenure is from age 5-6 years, i.e. when they succeed in controlling a harem, for close to life time, but are replaced when dead or incapacitated. Harems are stable even in the absence of a stallion, indicating voluntary membership. Adolescent mares leave their parental families to become members of another harem.
In Plains Zebra the adolescent mares are abducted, during an oestrus, by suitors who fight the defending family stallion/father. Successful stallions are bachelors who start a family, or family stallions enlarging their harem. Young stallions leave their parental families voluntarily at age 2-3 years and join bachelor stallion groups from where the family stallions are recruited.
An individualised dominance hierarchy excists with the stallion in the alpha position. It is based on individual knowledge and recognition of the members.
In the type 2 species Grevy's Zebra, African Wild Ass and Asiatic Wild Ass adult stallions monopolise territories in which they have the exclusive mating rights. Stallions are tolerant of any conspecifics entering their territory. Bachelor stallions behave subordinately – or fight for the possession of the territory which is a prerequisite for reproduction.
Mares join up to form anonymous and unstable groups or herds. The only stable unit is of a mare and her offspring. In Grevy's Zebra mares with foal join preferentially conspecifics of the same soial status, as do mares without foal.
Matings take place inside the territory. There is no lasting relationship of the mare with a particular stallion, and the mare may be mated by any stallion whose territory she is visiting.
Territories measure up to 10 or more square kilometres, and tenure is for several years.
Grevy Zebra territorial owners leave their territories for a few hours to visit a water hole, or for months when grazing and water conditions are below requirements, and re-occupy it upon return, unchallenged.

Abstract: Various forms of intensive sport activities places stresses on the musculoskeletal system of the horse while involve in any forms of the activity (race &/or training). The musculoskeletal system of the horse has an inherent ability to adapt to the demands of high speed exercise, though if a threshold in adaptive capacity is exceeded, then some forms of damages to the structures of the musculoskeletal system may result. In case, if the insult (race &/or training) continued, it may worsen the repair and adaptation process and put the horse at risk of more serious musculoskeletal injury.
The result of this research describe the finding of the study performed in different breeds of horses involved in various types of activity in Tehran’s riding clubs, concentrating on the types of injuries observed in those horses. The study was then focused on the types of injuries observed in various activities (events) horses involved in.
Totally 400 horses took part in various activities during race season (March – September) in Tehran’s riding clubs, out of which 26 horses injured, in most of which musculoskeletal system of the fore limbs were involved.
From the sexual aspect of the study the percentages of the stallions were more (54%) when compared to the mares (46%). In this study the relation between the sex, breed, age and the weight of the horses with anatomical site of the injury, outcome of the injury, climate and the type of the event (jumping, polo etc.) were studied and compare with each other.
Bibliography:
Hill AE, Stover SM, Gardner IA, Kane AJ, Whitcomb MB, Emerson AG, 2001. Risk factors for and outcomes non catastrophic suspensory apparatus injury in Thoroughbred race horse. J.A.V.M.A. 218, 1136-44
Johnson BJ 1993. A look at race horse breakdowns. J.Eq.Vet.Scie. 13, 129-32
Morse SJ. 1999. A longitudinal study of racing thoroughbreds; performance during the first year of racing. Aust.Vet.J. 77, 105-12
Peloso JG, Mundy GD, Cohen ND. 1994. Prevalence of, and factors associated with, musculoskeletal racing injuries of thoroughbreds. J.A.V.M.A. 204, 620-6

Abstract: Standard horse trailers, adapted from dead-weight delivery wagons, were never intended to carry live weight. Horse magazines and scientific, veterinary, animal behaviour, and engineering journals indicate the consequences: scrambling, trailer sway, equipment damage, loss of tow vehicle control, jack knifing, rollovers, and injuries to horses, handlers, and rescuers. The standard horse trailer cannot meet motor vehicle regulations requiring trailers to halt within 9 metres (30 feet) at 32 kilometres (20 miles) per hour without jack knifing. Equipment intended to protect the horse in transit adds to travel hazards. University of Guelph Ontario Veterinary Clinic surgeons report that head, throat, chest, shattered shoulder blades, butt bar or chain injuries to hocks and legs, and pastern injuries, in that order, are common. Internal, back, and hindquarter injuries also result due to the horse“s forced high-headed, wider hindleg stance or falling during transport. The horse”s sacroiliac joint, not intended to be weight bearing, is easily dislocated by pathologists. This is why for centuries horsemen have released tension from horses“ backs and necks by ”showing them the way to the ground.“ It was Italian cavalryman Federico Caprilli”s forward seat which removed strain on the horse“s hindquarters and freed its head to balance. More demanding jumps, slides and races were possible. Today, only two horse transport designs allow the horse to balance automatically and naturally during transit. Strain on the horse”s hindquarters is removed. These transports, adapted to equine behavioural needs, meet Office International des Epizooties (OIE) standards for handler and horse safety and welfare, and automotive safety. Japanese and U.S. studies on performance horses transported according to OIE standards have indicated that these horses have a competitive advantage. Applying these standards allows a horseman to complete a journey with the same horse that began it.

Abstract: Two distinct types of social organisation have evolved in the Equidae. Type 1: In Horse Equus przewalskii, Plains Zebra E. quagga and Mountain Zebra E. zebra the adults live in non-territorial, stable, one-male families and as single bachelors and in bachelor groups. Family stallions have the exclusive mating rights with the mares in their harems. These consist of up to 6 unrelated mares plus their offspring, totalling up to 20 members. Mares stay in their harems until death. Stallions' tenure is from age 5-6 years, i.e. when they succeed in controlling a harem, for close to life time, but are replaced when dead or incapacitated. Harems are stable even in the absence of a stallion, indicating voluntary membership. Adolescent mares leave their parental families to become members of another harem. In Plains Zebra the adolescent mares are abducted, during an oestrus, by suitors who fight the defending family stallion/father. Successful stallions are bachelors who start a family, or family stallions enlarging their harem. Young stallions leave their parental families voluntarily at age 2-3 years and join bachelor stallion groups from where the family stallions are recruited. An individualised dominance hierarchy excists with the stallion in the alpha position. It is based on individual knowledge and recognistion of the members. Type 2: In Grevy's Zebra E. grevyi, African Wild Ass E. africanus and Asiatic Wild Ass E. hemionus adult stallions monopolise territories in which they have the exclusive mating rights. Stallions are tolerant of any conspecifics entering their territory. Bachelor stallions behave subordinately – or fight for the possession of the territory which is a prerequisite for reproduction. Mares join up to form anonymous and unstable groups or herds. The only stable unit is of a mare and her offspring. In Grevy's Zebra mares with foal join preferentially conspecifics of the same soial status, as do mares without foal. Matings take place inside the territory. There is no lasting relationship of the mare with a particular stallion, and the mare may be mated by any stallion whose territory she is visiting. Territories measure up to 10 or more square kilometres, and tenure is for several years. Grevy Zebra territorial owners leave their territories for a few hours to visit a water hole, or for months when grazing and water conditions are below requirements, and re-occupy it upon return, unchallenged. Except for a few small populations, the extant equids live in semi-arid to arid regions where environmental conditions force them to migrate seasonally or opportunistically. The ranges of the various species overlap: Mountain Zebra and Plains Zebra in South Africa and Namibia, Plains Zebra and Grevy's Zebra in Kenya and Ethiopia, Grevy's Zebra and African Wild Ass in Ethiopia, Asiatic Wild Ass and Przewalski Horse in Mongolia andChina. Although, in the overlap zones, individuals of different species are using the same resources like water and grazing simultaneously and next to each other, they rarely make closer contacts. Infanticide has been recorded in captive situations.

Abstract: The Przewalski`s horse (Equus f. przewalskii) was extinct in the wild by the mid-sixties of the past century. The species only survived due to captive breeding from 13 founder individuals. In 1992 a reintroduction program was initiated in the Great Gobi B Strictly Protected Area in southwestern Mongolia. During it“s initial years, the project concentrated exclusively on P-horses. In the past decade activities have expanded significantly. The ecological project start point can be summed up as follows: i) species is extinct in the wild, ii) severe bottleneck, iii) practically no ecological data prior to extinction, iv) released into an extremely harsh, highly variable and poorly understood environment. The ecological knowledge constraints were compounded by i) highly emotional species, ii) simultaneous and competitive projects, iii) logistic nightmare, iv) non-scientific basis in planning phase. By the late 1990s project leadership and management was overhauled with research and scientific data firmly integrated into the decision-making process. Early scientific input concentrated on determining causes of death and low reproductive rates. The elucidation of the effects of endemic piroplasmosis on the population and subsequent management changes lead to remediation this deadly problem. P-horses have been fitted with ARGOS and GPS-ARGOS collars in order to determine home range and habitat preferences. Simultaneously the Mongolian wild ass and the wolf have been studied with these methods in the shared habitat. Satellite-based technologies provide the backbone for all habitat related project issues. At the onset (digitized Russian maps) data collection was restricted to the Eastern part of the Gobi B. Subsequently the spatial scale encompasses the entire Gobi Region in Mongolia and Northern Xingjian in China (e.g. Landsat, MODIS, NOAA, SRTM). Research has also focused on the role, needs and possible impacts of local semi-nomadic herders that use the protected area. Capacity building and training workshops (e.g. construction of fuel efficient stoves, felting) have been initiated. In 2007 a trans-boundary project in collaboration with the Xingjian Institute of Ecology and Geography of the Chinese Academy of Sciences, was initiated. This project aims to support rural communities of nomadic pastoralists living in the trans-boundary area of the Dzungarian Gobi, in China and Mongolia. Today, this project and the one in Hustain Nuruu (Mongolia) are the only ones that have resulted in free-ranging non-supplemented populations. In the Gobi B area some 120 (status 05.2008) P-horses roam in the protected area. In 2003 the IUCN downlisted the Przewalski\'s horse from to . Further downlisting to is predicted to occur in 2011. There is no consensus on when a reintroduction program is deemed successful. Clearly viewing the self-sustainable re-establishment of a population as a successful end-point is at best a short-term approach, constrained by time (today and now). Comprehensive interdisciplinary monitoring and research was and is the foundation for management strategies and decisions in this project. However, a self-sustaining financial base in conjunction with dedicated training and empowerment of local scientists and residents constitute essential prerequisites for the project”s future. Defining success and thereby inferring an end-point can easily lead to complacency compromising species persistence. As others have stated the ultimate project objective must be a constantly re-evaluated state of population persistence without intervention.