6. HAVE YOU OBSERVED A CORRELATION WITH ESTRUS/ LAMBING DATES IN CERTAIN GENETIC LINES? (EX.- SISTERS, MOTHER, GRANDMOTHER, ALL LAMBING NEAR THE SAME TIME?) • Each producer responded that yes, certain families consistently lamb about the same time each year. • Outside factors do intervene in this common occurrence; such as use of cidr’s, AI, and environmental factors. • Radell Schrock added
Greg Ahart of California responded “Bad mothers don’t reproduce in my operation, but I will keep the daughter of a good mother based purely on the expectation that she will be a good mother as well. 3. ARE THERE BEHAVIORS THAT WOULD LEAD YOU TO CULL A EWE? DESCRIBE THE BEHAVIOR. • Non-responsive to newborn lambs, losing lambs in the mixing pen • ‘Tasmanian devil’ behavior in the lambing jug • Nervous personality
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“Certain ewe families and daughters of certain rams are always more represented in our early lambing group. On a similar note, while prolificacy is considered to be lowly heritable and impacted more by nutrition than genetics, we have seen certain ewe families and daughters of certain rams tend to be quicker than their peers to step up and throw in an extra lamb when the nutrition levels are ideal. For example, one
• Not letting lambs nurse • Paul Russell of Indiana shares, “We had one ewe with a bad attitude and we tolerated her, her daughters and granddaughters, who all were very high-quality sheep, but all had the same bad attitude. We finally culled the whole line of them, solely because of their aggressive behaviors.” Radell Shrock of Virginia added “What you tolerate is
what you will have… multiplied! I have culled some animals with ideal phenotype simply because they were too wild or didn’t milk well enough.” 4. DO YOU PRIORITIZE CERTAIN EWE FAMILIES WHEN KEEPING REPLACEMENT EWE LAMBS OR SELECTING STUD PROSPECT LAMBS? • With only 2 exceptions, all respondents said they absolutely consider the maternal performance line when considering both ewe lamb replacements and stud ram prospects. • One producer gives priority to twin lambs born by Jan.25 to mothers that are gentle and maintain good flesh. • Bill MacCauley of Pennsylvania added “We also find maternal traits are passed through the ram lines and we have culled rams that do not produce good mothers.” 5. IF YOU PRIORITIZE CERTAIN EWE-BASED GENETIC LINES, TO WHAT DEGREE ARE DECISIONS BASED ON: • past performance - responses averaged 51.33% • genotype - responses averaged 11.5% • phenotype - responses averaged 26.33% • Some producers also consider qualitative measures such as BW, WW, 120 D WT and REA.
year we had more triplets than usual. There was one large breeding group that we had pastured on a field of millet that was at the perfect grazing stage and free of any parasite load. It was no surprise that this group ended up having a much better lambing percentage than the others. But the diet they received during breeding wasn’t the only important factor. All the ewes that had triplets except one were daughters of a ram we had already noted from previous years tended to produce prolific daughters.” In a search for quantitative evaluation of lactation, the following article from SMALL RUMINANT RESEARCH , volume 7, issue 3, May 1992, authored by Sakul, W.J. Boylan adds insight to our topic. Evaluation of U.S. sheep breeds for milk production and milk composition: Abstract: Seven standard, Dorset (D), Finnsheep (F), Lincoln (L), Rambouillet (R), Romanov (Ro), Suffolk (S), Targhee (T), and three synthetic breeds of sheep, Synthetic I (F×L), Synthetic II (D×R), and Synthetic III (F×L) × (D×R), were evaluated for milk yield (MILK, 1), average daily milk yield (ADY, ml) and contents of fat, protein, lactose and total solids in a five-year lactation trial. Highly significant differences were observed (P<0.01) among breeds for all traits (30 d postpartum after weaning) except percentages of fat and lactose. Average total milk yield was 65.51 in 122 d, and average daily
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