Livestock in 1999 included some 329,000 head of cattle, 594,000 goats, 165,000 sheep, 61,000 pigs, and four million chickens. Social prestige has traditionally been derived from ownership of cattle. This, together with improved sanitary conditions, has resulted in the accumulation of large herds of poor-quality stock; for example, the average milk yield per cow is only 350 kg a year (17% of world average). Total milk production was estimated at 23,000 tons in 1999. Meat consumption is estimated at only 48 calories per person per day, only one-tenth of the world's average. Production of meat in 1999 was 24,000 tons. The herds retard economic development by cutting down the amount of land available for food growing, and they destroy pastureland by overgrazing. Through various technical assistance programs, the government is seeking to eliminate excess cattle, improve the remaining livestock, and introduce modern stock-raising methods.