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VikingNews AU 2019-2
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what is
heterosis
? heterosis is created when two unrelated breed
s with dif- ferent genetic heritage are crossed together. the lower the relationship between breeds, the higher the heterosis that you get. the effects of heterosis are the opposite of inbreeding
depression which is a decline in perfor- mance of dairy cattle. research indicates that heterosis can really improve traits like vitality, fertility, health and survival. there is also an indication that heterosis can increase production compared to the parent average. goldencross heterosis ? your free gift enjoy the free benefits of heterosis when using goldencross ® heterosis gives you natural resistance against the effects of inbreeding. your herd will remain healthy and long-producing. by using a three-way cross you can achieve steady heterosis of 86% in your herd. this way the genetic heritage of your herd remains stronger. heterosis is the extra added genetic value that is gener- ated above the parent average. when we have breeds that share the same breeding goals, we can get improved results from crossbreeding. as an example, we have two dairy breeds and we cross them together (eg. vikingholstein and vikingjersey), we will keep the desired traits in dairy production but as an add- ed benefit the crossbred offspring will have improved fertility and health traits. counteracting inbreeding pure breed populations face the threat of inbreeding de- pression because animals are starting to become more closely related to each other. inbreeding depression is a big threat in purebred populations because it effects negatively on traits connected with survival and overall fitness, e.g. reproductive rate, health and disease resist- ance. hence, it increases the risk of recessive lethal dis- eases and defects, reduces the performance of your cows and also reduces the adaptability to production environ- ments. the opposite of inbreeding depression is hybrid vigour (heterosis) where we have animals whose parents are not related at all. this increases fertility, health and even pro- duction because this crossbred animal doesn?t get the possible negative traits in one breed population (eg. pos- sible hoof health issues typical for holstein). 100 110 120 130 140 f2 breed c breed b breed a breed a breed b breed c parent average heterosis 8 vikingnews | september 2019
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