The value of F-1 dairy Bos taurus Bos indicus embryos for milk production in poor environments

Literature summaries were used to estimate the economic value of F-1 dairy crosses of Bos taurus and Bos indicus for milk production in unfavourable environments, in relation to five continuous breeding systems. The continuous systems included purebreeding (B. taurus or B. indicus), crisscrossing, and B. taurus-B. indicus synthetics. Performance in unfavourable environments was considered from three sets of data in the literature (from Brazil, India and a world review). The evaluation performed was for herds producing the same total milk yield per year. Due to higher yields from F-1 cows, fewer cows are needed, and also, due to their longer herd lite, fewer replacements are needed. Break-even points for the use of F-1 embryos were calculated, measuring the extra breeding cost justified to produce F-1 heifers by embryo transfer (ET). The break-even points for extra F-1 costs, compared with the best alternative best breeding system (crisscrossing), ranged from US$229 to 562 in moderate and good environments, but rose to US$617-1025 in poor environments in Brazil. The extra costs to produce a replacement F-1 heifer by ET are less than $400 for ET costs up to $100 per transfer, but increase appreciably for higher ET costs. Thus, if good rates of ET can be achieved, even at current costs, the production and use of F-1 cows in unfavourable environments may be profitable. The F-1 embryos might be produced by using B. taurus semen on B. indicus ova in developing countries, or by using semen from B. indicus males on ova collected from surplus B. taurus females in developed countries and exporting the embryos.