The Pilgrim, Hungarian, Chinese, Selected C hinese, Synthetic (developed from Pilgrim, Chinese and Hungarian), Selected Synthetic, Large Embden and Small Embden strains of geese raised from 1980 to 1988 at the Greenbelt farm of the Centre for Food and Animal Research (formerly Animal Research Centre, and Animal Research Institute) in Ottawa, Canada varied significantly in body weight at 9 and 16 wk of age. The Large Embden strain weighed more than the Small Embden strain in 1986, and both were heavier than the Pilgrim strain (P < 0.05). Significantly different body weights for the Large Embden, Small Embden and Pilgrim strains averaged over sexes were 5.03, 4.45 and 3.59 kg, respectively, at 9 wk, and 6.15, 5.49 and 4.33 kg, respectively, at 16 wk. The Pilgrim strain was similar to the Chinese and Synthetic strains in body weight, whereas the Hungarian weighed consistently less (P < 0.05). Body weights for the Pilgrim, Chinese, Synthetic and Hungarian strains averaged over sexes and years 1980, 1983 and 1986 were 3.70, 3.56, 3.70 and 3.37 kg, respectively, at 9 wk, and 4.65, 4.43, 4.53 and 4.17 kg, respectively, at 16 wk. From 1982 onwards, the Chinese and Synthetic strains were selected for four generations in order to increase egg production over a 24-wk laying period and body weight at 16 wk of age, and to simultaneously decrease total fat (abdominal and intestinal). These Selected Chinese and Synthetic strains not only weighed significantly more than their corresponding Chinese and Synthetic strains maintained as randombred populations, but were also heavier than the Pilgrim strain. Corresponding body weights for Selected Chinese, Selected Synthetic, Chinese and Synthetic strains averaged over sexes and years 1983–1988 were 3.72, 3.69, 3.47 and 3.59 kg, respectively, at 9 wk, and 4.69, 4.77, 4.26 an d 4.31 kg, respectively, at 16 wk. The range in heterosis estimates for specific strain cross combinations were as follows: -6 to 8% for the Large Embden × Selected Chinese, 2 to 6% for the Selected Chinese × Selected Synthetic, -2 to 3% for the Selected Synthetic × Selected Chinese, -8 to -9% for the Large Embden × Small Embden, -1 to 1% for the Small Embden × Selected Chinese, and 4 to 8% for the Small Embden × Selected Synthetic. The variability among heterosis estimates for body weight was specific to strain crosses and subject to sampling associated with low number of sires used to produce crossbred offspring as well as the absence of reciprocal crosses. Larger studies evaluating all possible cross combinations of strains for additive and non-additive effects are warranted. Although, the Selected Chinese and Synthetic strains achieved genetic superiority for body weight, the inherent potential in the Embden strain demonstrated considerable merit for use as a terminal sire in a crossbreeding program for commercial geese production. Key words: Embden, Pilgrim; Chinese, Synthetic, Hungarian geese, crosses
Occurrence of Pulmonary Adenomatosis (Jaagsiekte) in sheep of animal research institute: the strategy of working with pulmonary adenomatosis in a flock of sheep
