Feeding young ruminants Flashcards
Describe the differences between the GIT of ruminating cattle and non-ruminating calves
Ruminating cattle:
- solid food source (concentrates and forage)
- 70-80% rumen size
- Numerous absorptive papillae
- pH = 6.2 - 7
- anaerobic microbiome for bacterial growth
Non-ruminating calf:
- liquid food source (milk)
- 25-30% rumen size
- no absorptive ability due to lack of developed papillae
- pH = 5-5.3
- sterile microbiome
What is needed to help rumen development?
Inoculation and establishment of anaerobic ruminal microbial ecosystem
Initiation of starter feed consumption
Fermentation processes and absorption mechanisms
What stimulates the growth of papillae in the rumen?
Presence of VFAs
What is paraketosis?
Excessive development of papillae
What is the effect of low rumen pH?
Undesired shift in microflora
Inefficient digestion
Decrease in rumen motility
increased keratinisation
Weaning = common time for low rumen pH
Describe the development of the rumen microbiome
Sterile in newborn calf
Gain bacteria from environment and colostrum/milk
Starch (concentrates) => increase in gram -ve bacteria
Fibre (forage) => increase in gram +ve bacteria
Describe skimmed milk replacer
Contains major milk proteins
Forms a clot (stays in abomasum for longer => feel full for longer)
Expensive
Describe whey milk replacer
Made of mostly lactose
no functional abomasal clot
Describe plant-based milk replacer
Contains non-milk based proteins
Not always easily digested as rumen not developed
What are the aims of feeding solids to calves?
Stimulate microbial population
Stimulate rumen papillae formation
Development of rumination
Increase rumen capacity
Provide energy
Impact behaviour
What is the aim of concentrate feeding in calves?
Provide VFAs from starch:
- microbial fermentation
- rumen epithelial development
- provide energy
Describe how to concentrate feed calves
small amoutn Offered from day 3 after milk
Consumption starts at 2 weeks
Energy source at 3 weeks
Rumen functioning at 10-12 weeks
Calves housed together => learned behaviour
What are the aims of forage feeding calves?
High fibre and lignin:
- development of ruminal muscular layers
- mitigate low rumen pH
- establishment of microflora prior to weaning
- chopped to 2” long - improves intake of concentrate
Introduced from day 3
should be available by 2 weeks
Why is early water consumption important for calves?
rumen development
improved grain retention
better starter intake
provision of some GI bacteria
When are beef calves usually weaned?
6-8months
When should creep feed by introduced to beef calves?
6-10 wks prior to weaning:
- reduces stress
- minimise drop in performance
- reduce pneumonia risk
What should dairy calves be weaned
commonly weaned at 8 wks
Minimum = 6wks
What is step-down weaning in dairy calf weaning?
Encourages starter intake during pre-weaning period
25-50% reduction in milk 10-14 days prior to weaning
2nd reduction 5-7 days pre-weaning
Increased solid feed consumption =>
- rumen development
- higher starter intake
- high BW gain after weaning
What are the signs of problems with the transition at weaning?
reduced growth rates
GI issues e.g., bloat or diarrhoea (Scours)
increased levels of disease e.g., pneumonia
Describe an appropriate diet for dairy calves 0-8wks old
Whole milk/milk replacer
Ad lib concentrate and forage
Describe a diet for dairy calves 8-10 wks old
Eating >1-2kg concentrate
Gradual decrease of milk
Increase amount of concentration
ad lib forage
describe a diet for a dairy calf from 10 wks onwards
Concentrate
forage
moving to higher percentage of a higher energy dense forage
Describe the diet for beef calves at birth
milk from dam
ad lib access to dam
Describe the diet for beef calves on the run up to weaning
Creep feed
Access to forage (grass/silage)
Describe the diet for a beef calf that has been weaned
Growers ration
Describe the diet for a lamb at birth
Milk from ewe/milk replacer
ad lib access to creep feed
Describe the diet for lambs at weaning
~60-90 days
Creep feed/grass
Describe the diet for a growing lamb after weaning
usually forage based
can supplement
Why should silage feeding be avoided in growing ruminants?
rumen cannto utilize silage properly until it is fully functional
What is the target growth for calves
0.8kg per day
55-60% mature BW at 13-15 mnths
What is the target growth for lambs?
250g per day (min)
Wean at ~12-14 weeks
60% mature BW at mating at 18-20 months
