图文网志无音乐:http://www.wretch.cc/blog/polecatsoQ/14489576 　　这篇文章撷取於< Ferret Husbandry, Medicine and Surgery >，在讨论近亲 繁殖。会特别先把这段文字分享出来，真的是最近听到一件很寒心的事情。这几年 来越来越多貂卖家，其中有已经繁殖到好几代的、也有今年才生第一胎的。不管你 是今年才养貂还是很多年前就养貂的，您知道您的血缘来自於何处吗？您知道您购 买小孩的最源头来自於哪里吗？不要认为网路上徵配台北宠物店买的和屏东宠物店 买的就不会有关系，试想一下中盘商收购貂去了哪里？ 　　不管您买貂是要生小孩或是结紮纯粹陪伴自己，请您一定要看这段文。不要认 为结紮了就是小事，近亲貂结紮了还是存在着免疫系统异常、抵抗病毒侵入能力降 低；而有想过要抱小貂宝宝的低出生率、新生儿的高死亡率，您或许觉得生有活就 赚到、生了死了也没差吗？发情、配种、怀孕到生产这过程母貂承受多少痛楚？ 　　整篇大概在叙述现代的貂刻意的培育已经远离原始基因。後面提到澳洲原有丰 富的品种但从２０世纪初因为政策关系没有新血缘进入澳洲，最危险的事造成基因 缺陷/弱化和近亲繁殖。说明为什麽澳洲政府不容许进口，原因是可能会传入可怕的 阿留申病毒。然後提到近亲的後果才又回头说近亲的 因素。 The unwanted ending … inbreeding The modern ferret is becoming increasingly removed from its original genetic pool by breeding, including inbreeding, for certain features. The ferret genetic pool needs refreshment by outbreeding to new ferret lines. The outlook for the Australian scene is that we had a variety of ferret (ferret-polecat?) strains coming in during the nineteenth and early twentieth centuries but no new bloodlines have been introduced for some decades. We have had years of interbreeding with this basic stock, but the danger is genetic weakness and inbreeding effects. We could consider that there is a population of inbred ferrets in WesternAustralia (where I live) and another in distant Tasmania where Christina Bernard with her interest in ferret genetics, lives. We would like to improve Australian ferrets by introduction of new blood lines but quarantine laws do not allow this. The possibility of inadvertent introduction of Aleutian disease, a chronic parvovirus disease, would be devastating (Ch. 8). Bernard considers that genetic fitness has no correlation with physical fitness and is the overall ability to leave surviving offspring who themselves will be able to reproduce themselves successfully. The signs of inbreeding would show as reduced fertility, increased congenital defects, 'bent-nose' condition, lower birth rate, higher neonatal mortality, smaller adult size and loss of immune system function. Some of these traits had been found in the Russian domestication experiments. 近亲繁殖会造成生育力降低、先天基因缺陷 提高、歪鼻子、低生育率、新生儿死亡率高、成体较正常小和普遍性的免疫系统异常。 The outcome for individuals with 'weak' genes is a deficient immunological system unable to prevent infecti on particularly by viruses. 缺乏免疫系统无法 防止感染，尤其是经由病毒感染的疾病。 Inbred laboratory animals, mice, etc. need to be in a sterile environment. 需在无菌的环境里 Endangered wild animals, in decreased numbers, are at risk of being wiped out by epidemics due to decreased immunological protection caused by unavoidable inbreed. The function of the immune system is to recognize foreign invaders to the body and destroy them by producing antibodies. The ability of the immune system to recognize foreign antigens depends on the genetic diversity of the major histocompatibility complex (MHC) genes. These are positioned close together on one chromosome and are inherited together as a unit called a haplotype. The MHC of a ferret is polygenetic with many genes and the alleles of each MHC gene are numerous within a population; it is polymorphic. Each ferret has two MHC haplotypes, one from each parent. The alleles of both haplotypes are expressed in a co-dominant manner, so greater diversity between the parents' haplotypes will give the offspring a better functioning immune system. Ferrets in an inbred population, with less diverse haplotypes, are at risk of being unable to recognize and respond to the challenge of infection. In the wild, the alleles will be numerous and variable adding to the genetic mix of the species concerned. In the event of disease, individuals of the species would survive as they would have the right mix of genes to overcome the infection and would pass that to their offspring, so more and more pathogens would be recognizable. It is considered that over time, the DNA can get stronger by changing or mutation and natural selection working on the changes. In fact, the MHC genes do have a high mutation rate as they are essential for species survival. 以上文字来自 Ferret Husbandry, Medicine and Surgery -- 可爱又调皮的貂蛮公主 快来瞧瞧他们可爱的模样 http://tinyurl.com/ycxa5mq X --

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