Reproductive and financial impact of a do-it-yourself artificial insemination programme compared with keeping a bull

The fertility of five dairy herds was studied for three years while they initiated a programme of do-it-yourself artificial insemination (DIY AI) and kept a herd bull, and the financial impact of the new programme was assessed. The herds of approximately 100 cows were all Friesian pedigree, changing to Friesian/Holstein. The DIY inseminators each operated within one herd and were all trained at the same centre. Within a herd, each cow inseminated by a bull was paired with a cow inseminated by AI. The paired cows calved during the same week and were of the same lactation number and genetic type. Each year 20 matched pairs, that is 40 cows per herd, were used, giving a total of 600 cow records. During the first two years, in the majority of herds the calving interval decreased in both the cows inseminated by DIY AI and by the bull. There was a higher culling rate for all cows in the first year, resulting in an improved Fertex score and improved profitability in the second year compared with the first. However, in the five herds combined it was only by the third year that the calving interval for the DIY AI cows was shorter (by 17.9 days) than for cows inseminated by the bull (P < 0.05). The first year of the DIY AI programme was a financial strain for the farmers, but the second and third years showed enough improvement to recover the losses incurred in initiating DIY AI, that is, the capital investment and learning period.