Student assignment. (requirement for course by Peter Kabai)

REPRODUCTION OF ICELANDIC HORSES KEPT UNDER FREE-RANGE CONDITIONS

Marit Smistad, Szent Istvan University, May 2006

Wild life ecology

The Icelandic horse was brought to Iceland by the Scandinavian Vikings in the late 9^th century. Due to the isolation of the country it has never been cross-bred with other horse breeds after its arrival, and thus kept its primitive characteristics.. The origin of the Icelandic horse has been researched twice; one comparative study with the Norwegian breed Nordland/Lyngen horse, where several similarities were found. Not only do the two breeds look very similar, it also came up that several of the Nordland horses taking part in the experiment proved to perform the tölt, a gait characteristic for the Icelandic horse. The genetic relations has also been researched, showing that the breed is closely related to Norwegian breeds, but also the Shetlands pony and the Mongolian horse.

(http://visindavefur.hi.is/svar.asp?id=5453)

The Icelandic horse has adapted to the environment, and due to the extreme weather conditions on Iceland , only the toughest horses survived the winter. Because of this hardiness and traditions through hundreds of years, Icelanders prefer to let their horses grow up like wild horses, and thus many of the young horses dont come in contact with people before the age of four to five years. This will for sure contribute to a totally different temperament and respect for humans compared to horses born in a stable with people around from day one. But how does the free-range breeding affect the attainment of puberty, the reproductive efficiency, the survival rate, the seasonal breeding pattern and the gestation period?

Òlafur R. Dyrmundsson from the Agricultural Society of Iceland collected data in a 15 year period about this theme..

The study of Icelandic horses kept under free-range conditions started in 1979, and is built on information collected from different farms on Iceland. In addition, analysis of horse records covering mares born during the period 1936 to 1976 at Lagafell farm on south Iceland, where the traditional Icelandic free-range management system of horse keeping is practiced, i.e. grazing on natural pastures with or without supplementary feeding in winter. The stallions were kept with the mares and replacement fillies throughout the year. Information is also collected from journals and newspapers on individual cases of foaling out-of season (winter) and on twin births in various parts of the country.

1) Attainment of puberty

Puberty was attained at the age of two or three years (70% and 90% respectively) for the mares, and stallions generally attained puberty by two years of age. Differences were observed her compared to horses kept indoor with good nutritional status. Some cases showed that well-fed horses could attain puberty already by one year of age..

2) Reproductive efficiency

The horses which took part in the project showed relatively high productive rate; with over 80% live foals born. Surprisingly 70% of the twin foals survived (16 cases). From this we can conclude that the survival rate is about the same as in housed horses..

3) Seasonal breeding pattern

78% of the foals were born in May or June. Out of season-birth is rare, but happened occasionally when both the mare and the stallion were in good nutritional status. Housed horses often foaled earlier (end of April/early May) because of human influence and earlier first oestrus because of the winter feeding.

4) Gestation period

Some problems are connected to this theme because it is hard to observe the accurate date of birth at the free-ranging horses. The approximate range is from 315 to 390 days, commonly 350 days, showing that the gestation period is somewhat longer in Icelandic mares.

To summarize we can say that free-range bred horses are influenced by nutritional deficiency, leading to somewhat delayed puberty, and in some cases barrenness. Still, the barrenness in Icelandic horses is relatively low compared to other breeds. The mares give birth to foals even many years after passing 20. They show a considerable variation in gestation period. The majority of horse breeders are now

adopting controlled mating management as a means of utilizing the stallions more efficiently, but the traditional way of horse breed in the natural way will probably continue on Iceland in many years.

Pictures: http://www.imh.org/imh/bw/iceland.html

BÚVÍSINDI ICEL. AGR. SCI. 8, 1994: 5157 Reproduction of Icelandic horses

with special reference to seasonal sexual activity

ÓLAFUR R. DÝRMUNDSSON

Agricultural Society of Iceland, Baendahöllin, P.O. Box 7080, IS-127 Reykjavík, Iceland

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REPRODUCTION OF ICELANDIC HORSES KEPT UNDER FREE-RANGE CONDITIONS Marit Smistad, Szent Istvan University, May 2006 Wild life ecology The Icelandic horse was brought to Iceland by the Scandinavian Vikings in the late 9^th century. Due to the isolation of the country it has never been cross-bred with other horse breeds after its arrival, and thus kept its primitive characteristics.. The origin of the Icelandic horse has been researched twice; one comparative study with the Norwegian breed Nordland/Lyngen horse, where several similarities were found. Not only do the two breeds look very similar, it also came up that several of the Nordland horses taking part in the experiment proved to perform the tölt, a gait characteristic for the Icelandic horse. The genetic relations has also been researched, showing that the breed is closely related to Norwegian breeds, but also the Shetlands pony and the Mongolian horse. (http://visindavefur.hi.is/svar.asp?id=5453) The Icelandic horse has adapted to the environment, and due to the extreme weather conditions on Iceland , only the toughest horses survived the winter. Because of this hardiness and traditions through hundreds of years, Icelanders prefer to let their horses grow up like wild horses, and thus many of the young horses dont come in contact with people before the age of four to five years. This will for sure contribute to a totally different temperament and respect for humans compared to horses born in a stable with people around from day one. But how does the free-range breeding affect the attainment of puberty, the reproductive efficiency, the survival rate, the seasonal breeding pattern and the gestation period? Òlafur R. Dyrmundsson from the Agricultural Society of Iceland collected data in a 15 year period about this theme.. The study of Icelandic horses kept under free-range conditions started in 1979, and is built on information collected from different farms on Iceland. In addition, analysis of horse records covering mares born during the period 1936 to 1976 at Lagafell farm on south Iceland, where the traditional Icelandic free-range management system of horse keeping is practiced, i.e. grazing on natural pastures with or without supplementary feeding in winter. The stallions were kept with the mares and replacement fillies throughout the year. Information is also collected from journals and newspapers on individual cases of foaling out-of season (winter) and on twin births in various parts of the country. 1) Attainment of puberty Puberty was attained at the age of two or three years (70% and 90% respectively) for the mares, and stallions generally attained puberty by two years of age. Differences were observed her compared to horses kept indoor with good nutritional status. Some cases showed that well-fed horses could attain puberty already by one year of age.. 2) Reproductive efficiency The horses which took part in the project showed relatively high productive rate; with over 80% live foals born. Surprisingly 70% of the twin foals survived (16 cases). From this we can conclude that the survival rate is about the same as in housed horses.. 3) Seasonal breeding pattern 78% of the foals were born in May or June. Out of season-birth is rare, but happened occasionally when both the mare and the stallion were in good nutritional status. Housed horses often foaled earlier (end of April/early May) because of human influence and earlier first oestrus because of the winter feeding. 4) Gestation period Some problems are connected to this theme because it is hard to observe the accurate date of birth at the free-ranging horses. The approximate range is from 315 to 390 days, commonly 350 days, showing that the gestation period is somewhat longer in Icelandic mares. To summarize we can say that free-range bred horses are influenced by nutritional deficiency, leading to somewhat delayed puberty, and in some cases barrenness. Still, the barrenness in Icelandic horses is relatively low compared to other breeds. The mares give birth to foals even many years after passing 20. They show a considerable variation in gestation period. The majority of horse breeders are now adopting controlled mating management as a means of utilizing the stallions more efficiently, but the traditional way of horse breed in the natural way will probably continue on Iceland in many years. Pictures: http://www.imh.org/imh/bw/iceland.html BÚVÍSINDI ICEL. AGR. SCI. 8, 1994: 5157 Reproduction of Icelandic horses *with special reference to seasonal sexual activity* ÓLAFUR R. DÝRMUNDSSON Agricultural Society of Iceland, Baendahöllin, P.O. Box 7080, IS-127 Reykjavík, Iceland

Notes (if any) by Peter Kabai: