Integrated hill sheep production systems.

End of Project ReportIn Ireland mountain, hill and peat lands above 150 m (OD) account for 1.5 m ha and sheep farming is a very important enterprise in these regions. Successive National Farm Survey reports show that flock productivity is low at about 0.75 lambs reared per ewe joined with rams. For the individual sheep farm, ewe flock productivity, lamb growth rate, market price and low input costs are the main factors affecting competitiveness and income. The options to improve the physical performance of the sheep enterprise on hill farms are limited by the proportion of lowland available. Sustainability must also be assured. Thus the objective of this project was to exploit the integrated use of hill and lowland in a sustainable manner. The project was carried out during 4 years (1998/99 to 2001/02) at the Teagasc Hill Sheep Farm at Leenane, Co. Mayo. The farm consists of 250 ha of hill land and 20 ha of reclaimed lowland and varies in altitude from 15 to 275 m above sea level. It is possible to cut silage on about 10 ha of the lowland. Average annual rainfall at the farm was 2124 mm for the 10 years 1993 to 2002 and 2188 mm for the four years of the project. Annual fertiliser application (kg/ha) of nitrogen, phosphorus and potassium to lowland was about 130, 18 and 45. The project involved two integrated systems aimed at maximising the use of hill (Hill) and lowland (Lowland) grazing respectively. The Hill and Lowland systems consisted of 200 Blackface ewes mated to Blackface rams and 150 Blackface ewes crossed with Belclare rams respectively. Hill ewes spend their first three breeding seasons on the hill and are then transferred to the Lowland system. The flock performance targets were, a) 0.9 (Hill) and 1.2 (Lowland) lambs reared per ewe joined, b) male Hill and Lowland lambs finished to carcass weights of 12 and 18 kg, respectively,and c) Hill and Lowland female lambs to weigh 40 kg at first mating (18 months) and 36 kg at about 6 months old, respectively. Reproductive performance for the Hill flock (0.90 to 0.95 lambs reared per ewe joined) was superior to that recorded for National Farm Survey hill farms. Ewes in the Lowland system reared 1.24 lambs per ewe joined. Average ewe mortality over the four years for the Hill and Lowland flocks was 6.7% in both cases with 1.9% and 3.1% of this due to sheep pulmonary adenomatosis in the Hill and Lowland flocks, respectively. The target carcass weights for male lambs were generally achieved. For both systems the weaning weight of male lamb was too low to achieve the targeted carcass weights by October without concentrate supplementation. The liveweight targets for Hill and Lowland female lambs were also achieved. Although supplementary lamb creep was introduced pre-weaning in the final 3 years compared with post-weaning in 1999, no obvious improvement in average weaning weight was recorded. However supplementary creep did help to ensure that the lighter male lambs reached the slaughter weight targets, especially in 2000 and 2001 but appeared to be less effective in 2002 when lambs remaining in October had to be housed and finished on concentrates to reach slaughter weight before the end of the year. During April and May pasture supply, with heights of 3 to 4 cm, may have limited ewe intake and therefore milk supply and lamb growth rate during early lactation. Heights of about 5.5 cm in June and 6 to 6.5 cm thereafter also need to be improved. Changes in the Lowland autumn resting date, nitrogen application times and timing of closing for silage are suggested management options to improve ewe and lamb performance.Measurement of roundworm parasitic burdens in ewes and lambs in 2001 and 2002 showed that levels were sufficiently low as not to affect sheep performance. The inclusion of the Lowland system greatly improved the overall financial performance of the farm with average gross margins per ewe for Hill (€40) little over half that for Lowland (€71). This effect can be generalised to areas where there are varying proportions of lowland to hill with the Hill and Lowland systems representing the extremes.European Union Structural Funds (EAGGF