Beef production lec 3 Flashcards
what are the increasing nutritional demands of a pred/lactating cow
energy and protein, 2% of LW DMI
what is the MJ ME required daily for a preg cow?
requires MJ ME 66-78,CP% 6
what is the MJ ME required daily for a cow in peak lactation?
requires 95 MJ ME, CP% 10
when is a cow in peak lactation?
4 months
what are the feed demands of young stock
o to increase growth rate need to increase ME and CP%
generally lower then cows
o usually in excess, most expensive to feed
o DMI 2.5% to 2.1%
in the SW slopes, what is the average daily growth of pasture?
o can get 10-15kg DM growth/ha/day
When does SR need to be maximised?
o have max SR over winter to utilise spring growth
o breeding cows have an increased SR
what is the ME of pasture
11 MJ ME
what is CMW
o Average weight of a group of heifers at which about 85% would conceive from a 45 day mating
o % of body weight 60-65% of mature weight
when does a heifer need to be joined to calve at 2 years?
9 months preg, 15 month joining
what is the CMW of british and European breeds?
British – 280kg-300kg
European + Bos indicus – 300-320kg
what would be the CMW of a cow that had a MW pf 515kg?
MW = 515kg
CMW = 0.6 x 515 = 310kg
if a heifer was weaned at 200 kg at 240 days and a mature weight of 515kg, how much ADG would it need?
MW = 515kg
CMW = 0.6 x 515 = 310kg
Weaning (240 days or 8 months) wt = 200 kg (actual)
Then must gain 110kg by 390 days (13 mths)
=0.73kg ADG for 150 days (steady growth)
what is the impact of BCS on fertility?
o higher BCS
higher % in oestrus (cycling)
higher % proportion pregnant
what are the KDP for heifer growth?
Weaning, yearling weight
• weighing allows time to reach CMW
