Beef Production from Jersey Cattle
October 2001
Stephen
T. Morris, Elly Navajas and Dean L. Burnham
Nutritional
Management of Pastoral Animal Production and Health
Institute of Veterinary, Animal
& Biomedical Sciences, Massey
University
This review was prepared for the C. Alma Baker Trust
Summary
1. A feature of the New Zealand beef industry is that the dairy
herd contributes 60% of the annual cattle slaughter comprising approximately
350,000 cull cows and 700,000 bulls.
2. An estimated 225,000 Jersey and 300,000 Jersey cross Holstein-Friesian
male calves are slaughter annually within the 1.2 million bobby
calf kill.
3. In order to develop profitable beef production systems for Jersey
or Jersey crosses a complete description of this breed for economically
important traits is required.
4. Jersey cattle have slower growth rates and lower carcass and
retail product weight compared to most breeds. On average Jerseys
grow about 25% slower than Friesians. There have been few studies
comparing the pre-weaning growth performance of Jersey male calves
but weaning weights are likely to be around 60-70 kg at 10-12 weeks
of age while Friesian male calves will be 90-100 kg at the same
age.
5. One of the most outstanding characteristics of beef from Jersey
cattle is the high level of intramuscular fat. Even under pasture
feeding conditions, the genetic potential of the breed to deposit
intramuscular fat implies that a high level of marbling can be obtained
at low carcass weights.
6. Beef from Jersey cattle has the lowest values of Warner-Bratzler
shear force an objective mechanical measurement of tenderness.
7. Taste panels have consistently rated meat from Jersey cattle
as being more acceptable due to its greater tenderness, juiciness,
flavour and overall acceptability.
8. Jersey cross cattle have monounsaturated fat concentrations
that are significantly higher than other breeds. The interest in
monounsaturated fat level arises from the fact that these fatty
acids, once seen as cholesterol "neutral", are now considered
cholesterol "lowering" and are preferable to high levels
of polyunsaturated fats.
9. Beef from Jersey cattle does contain more yellow fat compared
to Friesian and Friesian crosses. Consumers prefer white or creamy
white fat in beef as yellow fat is typically associated with old
cattle. However, the differences in fat colour at slaughter between
the breed groups were often not evident after chilling for 48 hours.
This reduction in fat coloration over time should be a factor for
consideration in terms of beef carcass grading standards.
10. The slower growing and lighter pre-slaughter live weights and
subsequent carcass weights of Jersey cattle would reduce the biological
efficiency of beef finishing systems utilising Jersey or Jersey
cross cattle because slower growing animals have a higher proportion
of their total feed intake contributing towards maintenance requirements.
In addition, the economic efficiency will be negatively affected
due to lower revenue if the payment system is based on carcass weight
alone.
11. Modelling analysis indicates that for the same feed consumption
from a fixed land area Jersey bulls stocked at 3.3 bulls/hectare
yielded 211 kg carcass and a gross return of $1293/ha. The comparable
figures for Friesian bulls stocked at 2.6 bulls/ha were a 260 kg
carcass and a return of $1497/ha. To achieve the same margin for
the Jersey system then there would need to be a 10 cent premium
rather than the 20 cent discount for those weight ranges that operated
on the AFFCO bull schedule for the period May 2000 to April 2001.
Alternatively Jersey bulls with high potential breeding values for
liveweight can be selected to achieve high liveweight gains.
12. The majority of the literature reviewed was 20 years old and
a large proportion was obtained in grain-based feeding systems.
It would be desirable to invest in a new characterisation of Jersey
and Jersey cross cattle for beef production under New Zealand pastoral
conditions.
13. The favourable composition of the intramuscular fat and the
high level of monounsaturated fatty acids found in beef from Jersey
cattle could be used as a positive marketing tool because of the
significance these findings in terms of human health.
14. Areas of potential research include; calf rearing systems,
liveweight gain under optimum feeding conditions, and sourcing potential
markets.
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