Low conception in dairy herds in New Zealand is a major problem with average conception in the 12 to 15% range. Low conception creates a large economic loss for the farmer. High performance cows are being culled for the wrong reason, they are being culled just for being empty. This means lower producing cows are being kept in the herd just to keep numbers up. Herd replacements are not being utilised efficiently, they should be replacing lower producers but are often replacing higher producing culls.
The attached article is based on USA data but the high nitrogen high protein and vitamin A deficiency is very relevant to our high nitrogen high protein lush pasture situation. it is well researched that excess nitrogen intake effectively reduces the conversion of carotene in the green pasture to vitamin A in the animal. Read the following with an open mind