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人工授精是动物生产保持竞争力的一项关键技术。自人工授精创立的那天起，它的目标就是最大化散播最好品种猪的基因。 自2007年起，子宫内人工授精 （PC-AI）便快速成为配种场的常规操作。其在西班牙的2011年的执行率超过60%，在2015年12月达到76%。这种快速的流行率取决于其下面的技术和经济优势： 1、更少的劳动力，因为 PC-AI速度更快 PC-AI最直接的好处便是减少了授精过程中劳动力（表1）。因为它更快，精液剂量更少，精液回流风险更低。但是，由于一些因素PC-AI也存在着相对较高的风险，如使用的精子数量更少、使用的精液剂量更少、子宫污染率增加等。这项技术可为选择培训更好、效率更高、待遇更高的员工提供机会。根据实际数据，1000头母猪场由传统的AI转变为PC-AI，伴随着劳动力的减少所产生的经济收益约为 €1,900。 表1：比较AI、 PC-AI的劳动力成本。假设母猪每次体温上升时注射精液2.4剂量，每年每头母猪分娩次数为2.38胎，AI每个月总劳动力工资为€1,386.6， PC-AI比其高20%。PC-AI技术可用于所有母猪，包括初产和后备母猪。 2、更少剂量的精液、精子数量 公猪每生产单位剂量精液成本中约60%是由固定成本组成。1000头母猪场使用传统人工授精法每剂量精液的成本约为€3.80，而使用PC-AI每剂量精液的成本约为€2.70，那么每年可节约约 €6,600。 引入PC-AI后，农场配种公猪的数量大幅下降。例如，西班牙配种公猪数自2005至2014年由70000下降至33000头，下降比例为53%（图1）。因此，配种公猪销售价格也上升了40%。配种公猪成本的提高也是对PC-AI精液剂量成本下降的一种呼应，因为配种公猪销售价格的上升使得传统授精成本、每剂量精液成本都出现了上升。
3、更少的农场公猪（不均匀性增加） 人工授精后代的均匀度是农场一项较难以测量和定量的指标。现代配种公猪由通过均匀度选育。但是，如果这些公猪存在一定的基因变异，后代的不均匀度将会增加、公猪替代率也会随之增加。 4、更少的公猪总数 这个因素是目前最具经济效力的因素，但是它却不是大多数情况下推行PC-AI方案的主要原因。 配种公猪提高的基因价值对选择参数有决定性影响，如肉质参数（转化率、平均日增重、瘦肉纺、大理石纹、采食量等）。母本参数有母性、泌乳力、乳头数、总产仔数、产活仔数、出生重等。 总之，PC-AI的引入对猪肉业有显著的经济影响（表2），也给种公猪和育种场由传统AI转变为PC-AI提供了一种挑战。现已证明PC-AI的有效及高效，还需进一步研究来接受这项技术的弊端，在养猪业各种挑战中保持竞争力。 表2: 1000头母猪场引入PC-AI的经济好处 附原文： Economic impact of post-cervical insemination on a farm AI （Artificial Insemination） is a key tool for maintaining competitiveness in animal production. From its beginnings, its goal has been to maximize dissemination of genes from the best breeding pigs. Since 2007, Post-Cervical Artificial Insemination （PC-AI） has been quickly incorporated into the routine practices of breeding farms. Its degree of implementation in Spain in 2011 was over 60% （according to the survey carried out by the Asociación Nacional de Porcino Selecto）， and in December 2015 this percentage went up to 76%, according to estimates by the author. This rapid implementation is due to its following technical and economic advantages:
Lower-volume doses and sperm counts Less boars on the farm （increased uniformity）
Less labour, because PC-AI is faster The immediate advantage of PC-AI is the need for less labour during AI （Table 1） because it is faster, it needs lower volumes and there is a lower risk of reflux （Hernandez-Caravaca et al. 2012.） However, PC-AI can be associated with a higher relative risk due to the following factors: Less spermatozoa are used （hence the importance of well-established quality）， less volume is used （which results in a lower immune stimulation of the uterus）， and there is an increase of the risk of uterine contamination. It is an opportunity to select better trained, more efficient and better paid staff. According to indicative practical data, the annual economic benefit in labour costs generated from changing from traditional AI to PC-AI on a farm with 1,000 breeding sows is estimated at approximately €1,900. Table 1. Comparison of the approximate costs of labour in traditional and post-cervical AI, assuming 2.4 doses per heat, 2.38 farrowings per sow per year, a gross monthly salary of €1,386.6 for the traditional inseminator and a 20% higher for the post-cervical inseminator. In the post-cervical scenario, this technique would be used with all sows, including primiparous and gilts. Lower-volume doses and sperm counts Almost 60% of the cost of producing a dose in a boar stud is comprised of fixed costs. A traditional dose on a farm with 1,000 sows costs €3.80 approximately, and a post-cervical dose €2.70 approximately, representing an annual savings of €6,600 in doses. The population of breeding boars has decreased dramatically since the introduction of the PC-AI. In Spain, for example, the population of boars has decreased by 53%, from 70,000 to 33,000 boars from 2005 to 2014 （Figure 1.） As a result, the selling price of breeding boars has increased up to 40%. The increase in the cost of boars is mirrored in the cost of post-cervical doses, which tends to meet the current cost of traditional AI due to the increase of the direct selling price of the boar or to the royalties per dose or piglet produced with the semen of genetically improved boars. Figure 1. Evolution of the census of breeding boars in Spain （MAGRAMA.） Less boars on the farm （increased uniformity） Uniformity through AI is a difficult parameter to measure and especially quantify on a farm. Current boar populations are made up by uniform, genetically selected individuals. Still, it is common sense to think that, if the population of original boars diminishes, uniformity will increase and also, if that population is the genetic elite, uniformity will be even greater and compensate the extremely high boar replacement rate in the boar stud （an average of 14 months in the centre, which means 85% replacements）。 Less boars on the whole （increased genetic value） This factor is by far the most determining economically but, surprisingly, it is not the main reason for the implementation of PC-AI in most cases. Increasing the genetic value of a population of boars has a decisive influence on the selection parameters, i.e., for finishers: meat parameters （conversion rate, average daily gain, lean percentage, marbling fat, intake capacity, etc）。 For female lines: maternal parameters （mothering ability, milk-producing capacity, number of teats, total born, viable born, weight birth, etc.） In conclusion, introduction of PC-AI has a very significant economic impact on the whole of the pork industry （Table 2）， and is a challenge for boar studs and breeding farms of parallel magnitude to that raised by the transition from natural service to AI. Its effectiveness and efficiency having been proved, further research is necessary on the accepted limits of quality for this technique （already investigated for traditional AI）， in order to remain competitive in the face of the challenges posed by the swine industry. Table 2. Estimation of the relative economic benefits obtained through introduction of post-cervical insemination on a farm with 1000 sows.
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来自： 昵称37357282 > 《待分类》
