Page 317 - The Welfare of Cattle

294 the WeLfare of CattLe

80.0%
70.0%
60.0%
50.0%
Holstein
40.0%
Jersey
30.0%
Guernsey
20.0%
10.0%
0.0%
1 2 3 4 5 6 7 8

Figure 25.5 survival rate by parity and breed from 1980 to 1995.
(Source: adapted from hare, Norman & Wright. )
9

removal rates will decline; feed costs are low, or feed supply is high on the dairy prompting a delay
in removal; and in herds that use rBST that increases persistency of production and allows animals
to have positive income over expense ratio longer into their lactation. Herds with purebred (regis-
tered) cattle often have lower removal rates because these cattle have more economic value from
their genetic base without additional operational costs.
Removal rates tend to be higher when the price of slaughter beef is high, feed costs are high,
the milk price is low or there is a surplus of replacement heifers in the herd or replacement heifer
market price is low.
Calculating a consistent and accurate turnover rate that can be used within and between herds is
a challenge. There are a number of formulas used today to calculate culling rates. Often these cal-
culations use different information especially in the denominator and are not directly comparable.
The use of the terminology “Turnover Rates” is recommended as a more accurate description of
what’s been measured than the historical “culling rates” terminology. The formula used should be
standardized across all data collection services and systems with the numerator equaling the num-
ber of cattle under review (herd, defined lactation, breed, etc.) leaving the herd across a specified
time (month, year, etc.) and a denominator based on how long each animal under review was in the
herd across the same time period, qualifying them as “at risk” of being removed. The time frame
may be days, months or years with a cow resident in the herd all year counting as one cow-year,
while one entering or leaving the herd with only 6 months of total residency counting as one-half of
a cow-year. Using cow-days would provide the most accurate denominator but requires more effort
to determine. Doing a monthly calculation is easier and can be compiled into an annual turnover
rate that is very similar to one calculated using cow-days. 10
Changes are urgently needed in standardizing and improving the turnover rates calculation
making it more useful, including: using four mutually exclusive destinations for an exiting cow to
include: (1) sale—animals going to other farms to produce milk or for reproductive reasons such
as embryo transfer, etc. (2) Slaughter—noncompetitive animals unable to remain in the herd and
are sold for immediate or eventual (after a period of fattening) slaughter for meat and valuable
by-products via sales. This would include those animals that are slaughtered on-farm slaughter
for employee or owner consumption. (3) Salvage—animals that are not sufficiently competitive
to remain in the herd and their meat is not usable for human consumption so they go to rendering.
(4) On-farm death. 10
Following the destination there should be opportunities to provide at a minimum primary and
secondary reason for the removal, and adding a tertiary or even more reasons will improve the