The need for intensification in animal production and the consequent pollution problem.
D000383:Agriculture; D000818:Animals; D000829:Animals, Domestic; D001947:Breeding; D002417:Cattle; D002645:Chickens; D003612:Dairying; D004531:Eggs; D004782:Environmental Health; D005260:Female; D005523:Food Supply; D005544:Forecasting; D008297:Male; D008460:Meat; D008892:Milk; D012037:Refuse Disposal; D012498:Sanitary Engineering; D012756:Sheep; D013552:Swine