I. Comparison with census data

Abstract

Abstract A national survey of farms with pigs was carried out in April 1977 to investigate herd sizes, numbers of gilts and boars per 100 sows, and statistics on breeds, breeding, and source of stock. There was a 14% response to the questionnaire in terms of pig holdings, taking numbers of holdings from the 1974 national census data. These holdings carried 55% of all sows reported in the census. Herd size in survey herds were considerably larger than the national average, but 41% of sows in survey herds where still carried in herds of 50 sows of less. (As an approximate comparison, 65% so sows in the national census were in herds of less than 500 pigs, i.e., of less than about 60 soes.) Overall, in survey herds there were 33 sows per responding farms, 20 mated gilts per 100 sows, and 6 boars used per 100 sows. The number of gilts per 100 sows in survey herds was larger than in the census data, i.e., higher replacement rate. The number of breeding boars per 100 sows was considerably smaller than in the cen...