A11. Feeding and Nutrition of Dairy Calves. Flashcards
Calf rumen anatomy;
Development of the rumen
It is depend on:
Increased nr of VFAs
Microbiome establishment
Papillae develop
Development of enzyme competence
- digestion of casein (milk protein; pro-renin)
- digestion of fat: lipase
- digestion of carbohydrate: lactose - lactase
The oesophageal groove reflex
Directing milk from the mouth to the abomasum
In order for this to work, milk/replacer needs to be at body temperature
The abomasum is the most important stomach in young calves.
rumen/reticulum : abomasum index %
Day0 38:40
3month. 64: 22
Adult 85: 4
Content prestomach and abomasum (in liters)
Some days 0.75 2
8 weeks 6l 7
12 weeks 14l 7
1 year 30l 10
At 12 weeks, they can start eat concentrate
Which is important for the papillae to grow
Protein
In the first 4-5 weeks, calves can degrade only milk protein
Calves are able to degrade the plant proteins after the age of 5 weeks.
Carbohydrates
after age of 4-5 weeks
get undegraded into the large intestinal tract and they are fermented there by the microbes
Fermentation products (lactate, volatile fatty acids) in large amounts can induce severe digestive disturbances (diarrhea)
Fat
Lipase in the salive starts the fat degradation already in the abomasum
Periods of calf rearing;
Birth (40 – 50kg BW):
o Colostrum, skim milk, acidified milk, milk replacer
o From the 2nd week at the latest: Calf starter concentrate (18% CP) + hay ad libitum
Periods of calf rearing;
Weaning (80 – 110 kg BW)
Days 60 – 90
Starter type feed (Rearing period)
Prerequisite of the weaning should consume: (0.8 concentrate + 0.5 – 0.6 kg/hay)/day
Periods of calf rearing;
Post - rearing (reach 180 – 200kg BW): 5-6 months
2 – 2.5 kg concentrate + roughages ad libitum/day Grower type feed (17% CP)
Colostrum intake;
1st (3-5day) week of life
within 2 h after birth 4 I
Colostrum content
o Colestrum is high in Protein, fat and IG
o High A, D, E, content – helps to prevent deficiencies.
o High in Mg to help digestion first feces.
Milk replacers: types, temperature, daily amounts;
Whole, skimmed, acidified, milk replacer need to be btw 38-40 2 – 3x/day liquid feeding. first month 6 liter first to 2nd = 8l decrease until day 70 (3-4month)
