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[en] Several countries are engaged in developing embryo transfer technology in both swamp and river type buffaloes. The technology is comparable to that used for cattle, except that collections are made earlier in the cycle and the number of embryos is much lower. The high cost of the gonadotrophin therapy combined with the inability to obtain a sufficient number of embryos from the superovulated buffalo have limited the practical application of embryo transfer technology and research in critical areas such as early embryonic development and a satisfactory superovulatory regime. Future research should examine the possibility of in vitro fertilization of buffalo oocytes as an alternative to superovulation and freezing embryos as a means of exchanging genetic material among buffalo rearing countries. (author). 24 refs, 4 tabs
[en] We conducted large-scale, replicated experiments to test the effects of two parallel power lines on area use, behaviour, and activity of semidomestic reindeer in enclosures. Yearling female reindeer were released into four 50 x 400 m enclosures; two treatment enclosures with power lines and two control enclosures. Reindeer from two herds, one from Kautokeino (domestic tame) and one from Vaga, (domestic wild) were tested separately and compared. Individual location within the enclosures was not affected by the power lines. Effects on restless behaviour were ambiguous, with slightly more restless behaviour in the treatment enclosures for the domestic tame reindeer, while the domestic wild reindeer maintained a stable level in the treatment enclosures, increasing with time in the control enclosures. Activity changes were slightly more common among animals within treatment enclosures for both herds, with no indication of habituation during the experiment. The domestic wild reindeer had more than three times the amount of restless behaviour than the domestic tame reindeer. Our study indicates that for reindeer in enclosures, the disturbance from a power line construction is negligible. This suggests that power lines are a minor disturbing factor compared to human handling when using fenced in areas like grazing gardens in reindeer husbandry.
[en] Numerous research studies have been conducted to access growth and meat characteristic differences between bulls and steers. In general, results have indicated that bulls grow more rapidly (15 to 17%), utilize feed more efficiently (10 to 13%) to an age or weight end point, and produce higher yielding carcasses with less fat and more muscle than steers. Steers have a slowly growth rate, more intramuscular fat, tenderer meat as compared with bulls. For further study on muscle gene expression profiles between bulls and steers, we constructed subtracted cDNA libraries between Longissimus muscles from three Chinese Simmental steers and three Chinese Simmental bulls with same age and same raising condition using suppression subtractive hybridization, genes that were differentially expressed in steer vs. bull Longissimus muscle were identified. More than 300 clones were randomly selected from each subtracted cDNA library. By PCR analysis, 223 positive clones were isolated from the subtracted cDNA libraries, by steers as Tester, bulls as Driver, respectively. By Longissimus muscles from steers and bulls cDNA as probes, high-throughput screening was carried out. We selected 84 differential expressed clones for further analysis, which showed that they represent 10 ESTs, all of them are known in cattle. Three functional genes, which are ACTG2, TPM2 and IGF-1, were chosen to do qRT-PCR to confirm the expression differentiation between steer LD tissue and bull LD tissue. The genes expressed in the former tissue were 1.96, 2.41, 2.89 times higher, respectively, than in the later tissue. These results implied that new candidate genes could be selected form the SSH library constructed in this research, and this could be a way to make the base of steer muscle special trait. (author)