Goose breeding and production in Canada.

In the 1950s, goose breeders were severely restricted in their ability to benefit from the application of quantitative genetic methodologies and expertise in the skilful practice of husbandry due to lack of scientific knowledge on the subject matter. Response to this concern led to the establishment of a foundation flock of Pilgrim geese at the Central Experimental Farm in Ottawa, and the development of technology for accurately recording rate of lay using trap nests, breedingwith pedigree records, feeding balanced diets, and employing disease control measures. In the following years, a number of studies carried out to improve the efficiency of goose production is described. These studies showed that older geese produced more eggs than 1-year-old geese, sex differences in production traits of economical importance, anipulation of photoperiod extended the rate of lay and altered the onset of egg production, increased spermatozoa concentration in semen collected from singly versus group housed ganders, the superiority of an artificial vagina versus aspiration for semen collection, and the advantage of inseminations on two consecutive days per week versus single insemination. Investigations of carcass quality of broiler geese showed that the Embden strain slaughtered at 64-66 days had relatively more breast meat and low scores for pin feathers, and meat quality of the Hungarian and Synthetic strains yielded 1-2% more breast cut than the Chinese and Pilgrim strains. The muscle contained 5-10% fat composed of mainly oleic (42%), palmitic (25%), linoleic (14%) and stearic (12%) acids with the Pilgrim and Hungarian strains having less muscle fat than the Chinese strain and strain crosses (<i>P</i> < 0.05). In a large study of Pilgrim geese, more than ten generations of selection for increased egg production resulted in an increase of 2 eggs generation 71. Heritabilities were estimated for body weights at 16 weeks and at housing (0.41-0.77), days to first and last egg (0.17-0.46), total and seasonal egg production (0.23-0.40), fertility (0.0-0.28) and hatchability (0.16-0.31), demonstrating potential merit for selection. Estimates of genetic correlation were relatively large between total egg production and days to first egg (- 0.48 to - 0.53), and days to last egg (0.66 to 1.07), but inconsistent with fertility (0 to - 0.40) and with hatchability (0.38 to - 0.12). In the 1980's, there was interest in reducing fat content in goose meat. Consequently, five generations of multi-trait selection in the Selected Chinese and Synthetic strains resulted in an increased body weight at 16 weeks of age (0.04-0.17 kg generation &#60;sup&#62;- 1&#60;/sup&#62; as a deviation from their respective Randombred control strains), and a small increase in egg production of the Selected Chinese strain, but eduction in total (intestinal and abdominal) fat content could not be confirmed. The heritability of body weight and breast muscle depth had the highest and lowest estimates (0.67 and 0.12, respectively), whereas heritability of intestinal plus leaf fat weight was 0.51 and for most individual carcass cuts was 0.70 or more. In general, estimates of phenotypic correlations among body weight, carcass measures and individual carcass cuts were small, but genetic correlations between lean content in carcass cuts and fat measures were negative. The evaluation of body weight at 16 weeks ranked the Large Embden, Small Embden, Pilgrim, Chinese, Synthetic and Hungarian strains in descending order, but subsequent studies led to the development of quantitative genetic methodologies and husbandry skills which demonstrated promise in achieving improved efficiencies for commercial goose production.