Goat Zero Grazing is common world wide for dairy goats in particular and for good reasons. Goats evolved in the Middle East i.e in dry sparse climate and rely on grazing technique rather than their immune system to cope with internal parasites. While cattle and sheep as adults are generally resistant to worms and coccidiosis as their immune systems cope with worm larvae etc , goats do not develop any age resistance. Many backyard goats have very limited grazing and would be better of with zero grazing as their small paddocks become very contaminated with worm larvae. Unfortunately worms are becoming resistance to worm drenches so are becoming more difficult to control. Also for dairy goats very few worm drenches are not registered for goats who's milk may be used for human consumption -only sheep and sometimes meat goats. This is because manufacturers don't want to pay for the R&D to determine the milk with-holding periods for goats . If goats have good yards and room for exercise I believe they are very humane. They need well designed feeders so no manure gets into their feed to spread worms. Also as goat lack the large amounts of lanolin in their coats as cattle and sheep have, they need shelter from the rain.
regarding global situation, Livecorp recommends zero grazing for goats in tropical countries as this is needed for both internal parasite control and also to protect goats from meliodosis ( a soil borne disease in the tropic) See http://www.livecorp.com.au/publications/australian-goat-manual-for-malaysian-farmers.
Dr Sandra Baxendell, PSM, BVSc (Hons), PhD MANZCVS, GCertAppSC(RurExt), GCertPSectMgt, PGDAppSc, MRurSysMan
Director, Goat Veterinary Consultancies -goatvetoz
Twitter http://www.twitter.com/goatvet @goatvet
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