The findings of a six-year long study by Dr Linda Mitchell of the Scottish Agricultural College, Aberdeen, have shown that a variety of crossing sires can be used to good effect with North Country Cheviot ewes.
The breeds used as crossing sires in the field trials were Border Leicester (BL) , Bluefaced Leicester (BFL), British Milksheep (BMS), Bleu du Maine (BDM) and Rouge de l’Ouest (RDO)
The lambs born to the different sire breeds were all vigorous at birth, with well developed coats and there were few lambing difficulties. The wether lambs produced were finished as stores. Border Leicester and Bluefaced Leicester crosses achieved finished condition at the heaviest weights and produced the heaviest carcases. The conformation scores of lambs slaughtered at uniform fatness were consistent across sire breeds. The findings of this first part of the research indicated that the different crossing sires used were all successful, with no evidence to suggest that any single cross was superior to the others.
The main part of the research project involved setting up and monitoring a breeding flock of cross ewes using the females from the first stage. Suffolk rams were put to all the cross-bred females, which were managed as a single flock. Again the outcome proved very positive, with high lambing percentages, and healthy, vigorous lambs. There was some variation in the growth and slaughter characteristics of the second cross lambs. However, in each case the final product was a high quality prime lamb with many of the characteristics of the North Country Cheviot and which compares favourably in terms of profit potential with most, if not all, of the crosses currently popular with producers in the U.K.
| Crossing Sire | BL | BFL | BMS | BDM | RDO |
| Mature Liveweight (kg) | 87kg | 86kg | 77kg | 78kg | 75kg |
| Lambing % as first crop ewe (live lambs per 100 ewes to the ram) | 203% | 200% | 243% | 193% | 191% |