Page 116 - Calculating Agriculture Cover 20191124 STUDENT - A

11-4 Large Animal: Beef, Swine and Sheep CH 11]

Calculating the offspring percent to market. To calculate the percentage of offspring that will be
delivered to market is a four step process.

Example: In a cow herd of 300 head, 37 cows did not conceive, were barren. Of those that were
pregnant and calved, 6 calves died at birth or shortly after. Of those calves that survived and
were weaned 2 calves died and were not weaned. Calculate the (a) Pregnancy Percentage,
(b) Calving Rate %, (c) % Calf Crop, (d) Weaning percentage, and (e) Calving % to Market.

Step 1: In a cow herd of 300 head, 37 cows did not conceive; were barren. What is the pregnancy
rate for this herd?
Solution:

(a) Pregnancy Percentage = [( (herd count − # barren) / herd count)] x 100%

Pregnancy Percentage = [( (300 − 37) / 300)] x 100%

= [( (263) / 300)] x 100%

= [ 0.8766 ] x 100%

(a) Pregnancy Percentage = 87.67%

Step 2: In a cow herd of 300 head the pregnancy rate is 87.67%, and (300 x 0.8767 =) 263 calves
should be born. Of those calves 6 were dead at birth or shortly after. What is the calving rate
for the herd?
Solution:

(b) Calving Rate = [( (# of calves born − # calf mortality) / (# of calves born)] x 100%
Calving Rate = [( (263 − 6) / 263)] x 100%

= [( (257) / 263)] x 100%

= [ 0.9772 ] x 100%

(b) Calving Rate = 97.72%

Step 3: During the year there were 257 calves born in a herd of 300 cows. Find the percent of calf
crop.

Solution: The calves considered are those born live and excludes those dead at birth or shortly after.

% production per species = # birthed / dams in herd x 100%

(c) % Calf Crop = # birthed / dams in herd x 100%

% Calf Crop = 257/300 x 100%

% Calf Crop = 0.8567 x 100%

(c) % Calf Crop = 85.67% calf crop (some cows did not breed or calf was lost)

Step 4: Of 257 calves born there are 2 that die and will not be weaned. What is the weaning % for
the herd?

Solution:
(d) Weaning Percentage = [( (calves to wean − # calf mortality) / ( calves to wean)] x 100%
Weaning Percentage = [( (257 − 2) / 257)] x 100%
= [( (255) / 257)] x 100%
= 0.9922 x 100%
(d) Weaning Percentage = 99.22%

INSTRUCTOR Copyrighted Material