Lambing hoggets is regularly presented to farmers as an obvious way to increase income, and has been used with varying degrees of success in the past. Current interest is driven by a renewed need to improve income, the availability of high fertility sheep, wider knowledge of better feed management, and pregnancy scanning. Clear management decisions are vital to incorporate lambing hogged into the total farm business. It's not a way to get a "bonus" lamb crop, and the full costs and returns of the enterprise must be considered.
Limitations to consider:
A strict business approach to consider these limitations is essential in order to see how the practice of mating hoggets will affect total farm profitably. The variable lambing percentage, barren hoggets and high lamb mortality are mainly a result of feed availability and season.
Lambs out of hoggets carry a large "maternal environment" burden, and consequently they stand a high risk of being culled from the flock on size and body weight, so they have little chance of reaching targets to be mated themselves as hoggets.".
Key Points for Success
Experience shows that hoggets should be at least 35 kg at mating. This means making sure that potential hoggets for mating are themselves at least 20 kg liveweight at weaning (100 days). An average of 24-25 kg at weaning would be a suitable weight to the accepted 2-tooth mating weight for the flock.
Depending on the district, good targets weights for hoggets that were going to the ram should be 35kg at mating in May, 40 kg in September, 55 kg in December and 60 kg at 2-tooth mating.
Weight is usually the limiting factor to start hoggets cycling (ie reaching puberty), and in the past, turning rams out with all the hoggets was a safe enough practice as only the heaviest would take the ram. But today's high-fertility breeds and crosses reach puberty at much lighter weights, so it's important to draft hoggets on liveweight (minimum of 35 kg) before joining with the ram.
Feeding to achieve mating weights
The main cost in lambing hoggets is the extra feed needed to achieve satisfactory target weights for good performance. Where soil fertility is low or management poor, then hogget lambing will be an economic failure. To achieve the required growth targets, feed hoggets to allow growth of above 100 g/day and preferably nearer 130g/day. This is 0.7 to 0.9 kg/week.
Before and during mating to get a flushing effect, hoggets will need to gain 70-140 g/day or 0.5 - 1.0 kg/week. This requires green leafy pasture 3-4 cm long providing 1300kg DM/ha. So after dry summers and poor autumns when target weights cannot be achieved, don't mate hoggets as you will condemn them to a lifetime of poor performance.
Mating should be for one cycle and not exceed 21 days. Use 2% of fit experienced rams which means avoiding ram hoggets or 2-tooths.
Run hogget mating mobs on flatter paddocks, separated from older ewes. Hoggets can benefit from teasing with vasectomised rams for 3 weeks prior to entire ram joining. If teasers are not available, run in well-fenced paddocks next to entire rams.
This is recommended to identify pregnant hoggets and those carrying twins for special feeding and care. Feeding levels allowing more than 100 g/day need to be maintained during pregnancy. In the 2-3 weeks prior to lambing control feeding levels to avoid large lambs from single-bearing hoggets.
Experience shows that hoggets are best left alone at lambing. They are generally good mothers and disturbance will only lead to lamb mortality through mis-mothering. Hoggets suckling lambs need special feeding and management, and the key is to avoid competition from other stock. Ideal pasture feed is 5 cm long providing 1500kg DM/ha and certainly not grazing down below 1300kg DM/ha.
Weaning hoggets' lambs
The decision when to wean hoggets' lambs must be flexible. If feeding levels cannot be maintained, then the hoggets' lambs must be weaned. Aim generally to wean as early as possible at a minimum of 15kg or at 8 weeks of age. Weight is generally a better criterion than age.
Recognise that these lambs weaned from hoggets will again need special management if they are to be offered for sale or kept as flock replacements.
A good animal health programme is essential if performance targets are to be met and this should cover internal and external parasites, vaccinations and blood profiles for mineral deficiencies. Experience shows slow-release rumenal treatments for internal parasites to be of great benefit. Dipping or pour-on treatment for external parasites should be avoided immediately after mating.
Effect on overall stocking rate.
This is a major consideration. Traditionally ewe hoggets have been classed as 0.9 ewe equivalents (EE), but this will need revising if they are going to be mated. It would be safer to consider hogget feeding needs as closer to 1.2 EE or even more, to make sure the operation is successful.
See AgFact 184 - Hogget mating.