(a) (i) Name two breeds of dairy cow - Leaving Cert Agricultural Science - Question 11 - 2020

The Holstein (Friesian) breed is suitable as a dairy breed due to its high milk yields, which make it an economically viable choice for milk production.

Dairy cows are culled primarily due to injury (such as lameness or bad feet) or low milk yield. Additionally, poor milk quality or diseases can also lead to culling.

Desirable characteristics of replacement heifers include good conformation for udder health and good feet/clean shiny coat, as well as good body condition score (BCS).

A heifer should give birth to her first calf at around 22 to 26 months of age.

The target weight for a heifer when she gives birth to her first calf is typically between 500 to 550 kg.

Two signs indicating imminent birth in a heifer are restlessness or signs of nesting behavior, and visible swelling of the vulva or discharge from the vulva.

Body condition scoring (BCS) refers to a method of assessing the fat reserves on an animal's body, measured on a scale from 1 to 9, with higher scores indicating better condition.

The body condition score of a cow is assessed through hand pressure applied to specific areas of the cow's body, including the back and ribs, to evaluate body fat and muscle cover.

A cow may have a low body condition score due to several factors including age, poor nutrition, illness or environmental stresses, leading to inadequate fat reserves.

A desirable body condition score for a cow at calving is typically between 3 and 3.5.