In my experience, rings are unequivocally more efficient because the kids and lambs suffer much less and present no complications due to castration. I saw young calves with rings too, and the rings seem to perform satisfactorily.

Louwrens and Ricardo, will rubber rings not supress growth of kids/lambs given that testesterone had not taken effect yet for muscle development?

A very enlightning response right there, thanks Louwrens. There is so much going on in RSA. Would you have that article by Berg and Butterfield. In Botswana we have to castrate since 3/4 of our cattle population is in the communal areas. This makes it difficullt to control movements of young intact males. To a greater degree, we are also promting grass fed beef just like Namibia. If we do finish animal in feedlots, we do not use growth stimulants, therefore that calls for penning intact males rather than castrated ones(steers).

Prescott & Lamming also released a study on the impact of castration on meat production in cattle, sheep, and pigs in 1964. You might find this interesting too.

The Journal of Agricultural Science / Volume 63 / Issue 03 / November 1964, pp 341-357

Thanks Mark, I will look it up.

Mark, may have the title of the article please.

Castration in animals at an eraliar stage before reaching sexual maturity does not effect the physical maturity, but in  sub-adults it cause drastic change in physiology. Livestock also pass through a trauma that affect their growth due to hormonal regulations. Both aggression and arrogance attitude persist in them for longer period.  

Dear Zibani Madzonga, I have a paper that describes the long term growth of kids from birth to maturity. They were castrated with rings at the 15 days-old.

The paper is: Araujo et alii, Journal of Agricultural Science 153(07): 1321-1340, 2015.