اثر اسيدهاي چرب جيره اي بر رشد فوليكولي بيان ژن Bone Morphogentic Protetion 15 در گوسفند

چكيده انگليسي :

Effects of Dietary Fatty Acids on Follicular Development and Expression of Bone Morphogenetic Protein 15 Gene in Sheep Niloufar Majidi n majidievari@ag iut ac ir Date of Submission May 2011 Department of Animal Science Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Ahmad Riasi riasi2008@gmail com Hamid Kohram hamid kohram@yahoo comAbstractDietary unsaturated fatty acids UFAs have been implicated in several reproductive processes through a varietyof mechanisms Some of these effects were altered by the type of FA fed The polyunsaturated FA of the n 6 andn 3 families seems to have the most remarkable effects on reproductive responses of ruminants This studyexamined the effects of supplementation of rumen bypass fats n 3 and n 6 poly unsaturated fatty acids PUFAs on ovarian follicle development and steroidogenic parameters and also the expression of one of oocyte derivedgrowth factors namely bone morphogenetic protein 15 in ovine oocyte Bone Morphogenetic Protein 15 is criticalfor ongoing development to ovulation most likely by regulating the proliferative and differentiative functions ofadjacent follicular cells Thirty 2 4 year old ewes were divided into three groups and were fed randomly a controldiet n 10 or supplemented with fatty acids n 3 n 10 or n 6 PUFAs n 10 over a 7 week period Oestruscycles were synchronized using progesterone releasing implant controlled internal drug releasing CIDR device Beginning at estrus ovarian follicular population was monitored daily via transrectal ultrasonography during this period the number of 2 mm follicles quantified Blood samples were collected every 3 day duringsynchronized oestrus cycle At 13 days following behavior estrus ewes were slaughtered and all visible follicleswere individually punctured and follicular fluid was released in a Petri dish Cumulus oocyte complexes wereisolated and divided into two groups split according to follicle diameter 2 4 and 5 mm RNA isolated fromoocytes of each follicle category of each sheep Relative expression of Bone Morphogenetic Protein 15 transcriptin oocytes was determined by Quantitative Real time PCR Feeding n 6 PUFA increased the number of medium size 2 3 mm and large 4 mm follicles There was a tendency for a higher number of follicular waves in n 6PUFA group compared with the other groups Feeding n 3 PUFA had no effect on follicular waves or number ofmedium size and large follicles in this group Plasma cholesterol High Density Lipoprotein and progesteronewere all higher in ewes fed a diet supplemented with n 6 PUFA than in ewes not received this supplement Diethad no effect on follicular fluid progesterone The Bone Morphogenetic Protein 15 transcript expression inoocytes that were collected from the 2 4 mm follicles was higher in n 3 and n 6 PUFAs group than control Butn 3 and n 6 PUFAs had no effect on expression of Bone Morphogenetic Protein 15 in oocytes that were collectedfrom 5 mm follicles The effect of follicle size on expression of Bone Morphogenetic Protein 15 was examined Results showed that the expression of Bone Morphogenetic Protein 15 in oocytes of 5 mm follicles wassignificantly lower than oocytes of 2 4 mm follicles In conclusion PUFAs especially n 6 PUFAs increased thenumber of large follicles and elevated progesterone which may be beneficial to consequent ovarian function AlsoPUFAs affect the expression of Bone Morphogenetic Protein 15 which is critical for regulating ovarianfolliculogenesis and steroidogenesis Key words poly unsaturated fatty acid follicle steroidogenesis Bone Morphogenetic Protein 15

مجيدي، نيلوفر

اثر اسيدهاي چرب جيره اي بر رشد فوليكولي بيان ژن Bone Morphogentic Protetion 15 در گوسفند

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