Application Of Microsatellite Markers For Genetic Diversity Analysis Of Endangered Punjab Urial (Ovis Orientalis Punjabiensis) In Pakistan
Material type: Book ; Literary form:
Publisher: 2014 Dissertation note: Biological diversity is now recognized as common concern of mankind and genetic diversity is the major driver of variation within and across breeds, which helps populations to adapt to environmental changes. There is very little importance is given to conserve wild sheep in previous years and its genetic diversity is decreasing day by day. Every now and then breeds are being haunted for crossing to some other imported breed without attempting to see if such efforts will be sustainable. For any breed development efforts thus, available genetic resources need to be characterized both at phenotypic and genetic levels (Khan et al. 2007).
Among the three levels of Biodiversity, one is Genetic variation which is suggested bythe International Union forNatureconservation (IUCN) for preservation (Mc Neely et al. 1990). The reason for it is that firstly; genetic diversity favors the changes as the environment changes and secondly; it prevents inbreeding depression (Reed and Frankham 2003). In this way genetic diversity increase the survival status and increase fitness of individuals.
Among many other wild animals present in Pakistan, there are 6 to 9 species of wild sheep (Ovis orientalis) are present which have different color and size of their winter neck ruff of males, saddle patches and horns color. Urial is a picture of Marco Polo in texture and hue. In Pakistan, ladakh urial, Blanford urialand Punjab urial are found in Gilget, Baluchistan and Punjab respectively. The discrepancy lies in the color of ruff among these 3 sub species (Roberts, 1977). Urial is among those precious wild animals that were hunted severely for trophy and other purposes in the past, that’s why included in red list of IUCN in vulnerable category (IUCN 2000).
Punjab Urial (A type of wild sheep – Ovis vignei punjabiensis) belongs to family bovidae which is the large family consisting of 140 species (Glazko et al. 2011) is facing serious threat of extinction in Pakistan is a medium-sized wild sheep which is included in IUCN red list of endangered animals (IUCN 2002). Urial is inhabitant in Western Central Asianregion stretching from northeast side of Iran and west side of Kazakhstan to Balochistan (Pakistan) and Ladakh regions of North India. The local name of Urial is Shapo, Arkar and Gad. Reddish-brown outstretched pelt that achromatizes during the winter is one of the distinct traits of urial (Aleem 1977; Schaller 1977). Urial is gregarious and sexually dimorphic as males are called rams and females as eves (Awan 2001). Male have weightof 40 kgand have large spiralled horns having height of 80 to 100 cm and females have comparatively less weight and height of 25 kg and 12 cm respectively and have uncurled horns.Females give birth to 1 or 2lambs in recent days of April (Awan, 2001). Males have a black ruff expanded from the neck to the trunk and notably longer horns. Table 1.1:Some physical features of the Punjab Urial (Awan et al. 2001)
Body weight 40 kg male; 25 kg female
Shoulder size 31-35 inches or 80-90 cm
Horn size 39 inches or 80-100 cm long male; 12 cm long female
Urial are found in moderate to very arid habitats, especially grasslands including agricultural fields and woodland areas (Valdez, 1982). Urial is herbivorous and eats grasses, shrubs and grains. The patch of salt range of Pakistan which fall in the area of Pind Dadan Khan, Choa Saidan Shah and Kallar Kahar is considered like a paradise on earth for the wild fauna. The fascinating hills of these areas are covered with thick trees and different wild plants are also the sanctuary of urial.
Table 1.2: The details of these sub species in IUCN list of endangered mammals (IUCN 2002).
Subspecies Citation in IUCN list
Ovis vegnei blanfordi VUC 1 Appendix ll
Ovis vegnei punjabienses ENA1cde,c1+2a Appendix ll
Ovis vegnei vegnei VUC 1 Appendix ll
In Pakistan, Punjab Urial dispersed throughout the Kala Chitta and Salt Range in a very little number(Hess et al, 1997). The Afghan Urial inhabits Baluchistan, Khyber Pakhtunkhwa, and Sindh Provinces. In Chitral District, little segregated populations of Ladakh urial are stillextensively distributed near the west bank of the Kunar river from Chitral southwards to Drosh. Ladakh Urial existence at the east bank of Kunar river and north of Chitral are not proved (Malik 1987). Total population estimate of urial is recorded by conducting several surveys. Reasonably 2,500 to 3,000 urial existsin Baluchistan (Hess et al. 1997). In 1993 the overall population assessment of Northern Areas was four hundred to five hundred Urial (Rasool 1999). In Pakistan, there were seemingly less than 600 Ladakh urial (Hess et al. 1997;NWFP 1992; Schaller 1971, 1977) but the number of urial decreased to 200 to 300 urial in all over northern areas (Rasool 1999). Based on the facts mentioned above there is dire need to conserve the Urial population in the country. The urial is one the precious fauna of Pakistan and provides us with wool and meat (fat, flesh or any eatable part). It is also important in economic way and in maintaining of ecosystem balance. In the beginning, sheep were reared for meat, milk and skin (Ensminger and parker, 1986). After 3500 B.C. men learnt to spin wool and so used wool in textile industry (Smith et al. 1997). So, because of increasing world population, there is great demand of these products and increasing day by day. That’s why we have to conserve is natural resource of Pakistan.Habitat fragmentationleads to the risk of exaggerated genetic drift and inbreeding in isolated population. So, there is need to save urial from these threats by enforcement of law and conserving it for future.
In all over the euchromatic genome Microsatellite markers are present. These markers are highly polymorphic (Ellegren 2000; Schlotterer 2000).A lots of polymorphic microsatellites have been analyzed in ruminants like domesticsheep, cattle etc. (de Gortari et al. 1997,1998 ;Hayes et al.1996; Jenkings et al. 1997) aiding the use of these in parentage testing.
Microsatellite markers are among the most reliable molecular markers for genetic characterization studies in animal species (Sunnucks, 2001) and are simple sequence repeats (SSRs) of 1-6 base pairs, repeated tandemly in coding as well as noncoding portion of DNA in prokaryotes and eukaryotes (Weber and May, 1989; Toth et al., 2000). Microsatellite markers have often used for genetic diversity studies because they areabundant, unbiased, widely distribution all over the DNA, highly polymorphic, easy in assessment like genotyping of these markers (Canon etal. 2001).Microsatellite markers aid in genetic differentiation and conservation studies (Peter et al. 2007;Rendo et al. 2004; Arranz et al. 2001).These are considered very useful markers for assessment of genetic diversity, parentage confirmation, genome mapping, disease research population genetic studies and conservation genetics. These are also reported to be efficient enough to identify within and among breed differentiation and population sub structuring in cattle (Glowatzki-Mullis et al. 1995; Ciampolini et al. 1995; Garcia-Moreno et al. 1996; Jarne and Lagoda, 1996; MacHugh et al. 1998).Therefore the conservation activities are very important to save Punjab Urial from extinction and the study is designed to explore its genetic diversity.
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