20. Dairy Calf Nutrition

1. naive immune system which is suppressed at birth

2. poor thermoregulation due to lack of fat and mm. tone...inability to shiver effectively

3. risk of hypoglycemia

what are the challenges associated with newborn calves

1. provide adequate colostrum

2. maintain clean environment

3. minimize heat loss

how can we prevent disease in newborn calves

1. dry calf

2. dip navel in 7% iodine

3. seperate from dam

4. hand feed colostrum

what is involved in the immediate care of a newborn calf

1. first milk produced after parturition

2. only 1st milking is high quality...the rest are considered "transitional"

3. high DM content

4. high IgG antibodies...largest Ab in milk

5. IgA produced in mammary glands and derived from blood

6. lactoferrin from mammary epithelial cells to protect against bacteria

what are the characteristics of colostrum

1. provide passive immunity

2. essential for disease prevention

why does colostrum matter

immediately and decreases linearly

intestinal absorption of antibodies declines...

decreased by 30%

what is gut absorption like 6hrs after birth

decreased by 50%

what is gut absorption like 8hrs after birth

24hrs after birth

when is "gut closure" considered complete marking the endpoint of when antibodies can be absorbed by the intestine

feed colostrum early

how can we achieve max absorption of antibodies

feed full amount (3-4qt) within 2-4hrs via voluntary consumption or feeding tube

what is the ideal colostrum feeding protocol

feed remainder by no later than 12hrs

if half to two-thirds of colostrum is consumed within 2hrs, what do we do with the rest of it

3 quarts

how much colostrum is needed for a 50-100lb calf

2 quarts

how much colostrum is needed for a <50lb calf

4 quarts

how much colostrum is needed for a >100lb calf

tube-fed/esophageal feeder

how should reluctant calves be fed colostrum

colostrometer: form of hydrometer which measures specific gravity and converts it to IgG concentration

how can we assess colostrum quality

>50-60 g/L (50mg/mL)

what IgG level is considered to be high quality

20-100mg/mL

what is the range of IgG in milk

measure total plasma protein using refractometer

how can we assess passive transfer

>5.5 g/dL total plasma protein

what value indicates adequate colostrum meal/passive transfer

1. affect ~40% of calves

2. increased disease risk

3. increased mortality

what are the characteristics of failure of passive transfer

>8 g/L (0.8 g/dL) IgG

what is the critical serum IgG level to avoid failure of passive transfer

1. heifer colostrum

2. colostrum leakage pre-calving

3. delayed feeding

4. low IgG concentration

risk factors for poor immunity

adequate production of colostrum in both volume and quality (antibody content) ...dependent on adequate nutrition

what does adequate immunity depend on

produce less volume with lower IgG concentration

how might you describe colostrum production of a heifer vs. that of a cow

high quality

high volume colostrum does NOT always equal ___ ___

lower IgG levels

how might you describe IgG levels in heifer colostrum vs. cow

lower IgG levels

how might you describe IgG levels of high producing cows compared to those producing less

1. frozen colostrum from cow in the same herd that is BLV and Johne's negative

2. colostrum replacer with >80 g IgG

3. colostrum supplement to be added to low quality colostrum...NOT for use on its own

what are some options for colostrum substitutes

immediately

when does gut permeability of antibiotics begin to decline

1. colostrum at birth

2. milk/milk replacer for weeks 0-6

3. starter (grain mix) introduction at 7 days

4. weaning transition

what is the feeding timeline for calves

>10% BW (15-20% ideal)

how much milk do we try to feed cows roughly...split into two daily feedings

7-10 times daily; 10 L

a calf on a cow will nurse ____ times daily and may ingest ___ L of milk

1. whole milk or waste milk...add milk replacer if needed

2. mastitis milk but MUST PASTEURIZE and avoid in newborn calves dur to bacteria transfer risk

what are some milk sources we can use for calves

1. dairy-based replacer ideal but can use soy-based for older calves

2. mix by weight (NOT VOLUME) using warm water

3. feed 2x daily

what are the considerations for using milk replacer

10% BW

what is the minimum value for feeding milk to calves

conventional

which feeding system for calves involves lower milk intake (saves $$ on milk replacer) and encourages starter intake for growth

accelerated

which feeding system has higher intake of milk and allows faster growth early on...starter intake catches up later

1. allow milk to bypass rumen by connecting cardia region to abomasum

2. fold of reticulum forms groove between esophagus and reticulo-omasal orifice

significance of the esophageal groove

1. allows milk to clot forming casein (protein which is bound to rennin enzyme) and fat

2. whey (water, minerals, lactose, other proteins) goes straight to SI for digestion

what happens to milk when it is digested in the abomasum

starter intake (grain)---> VFA production

what stimulates rumen development

60%

what is the holding capacity of the newborn abomasum

80%

what is the holding capacity of the mature rumen

grain

what is more important for rumen dvlp, hay or grain?

after weaning (alfalfa is best)

when is hay introduced into the diet to help reduce non-nutritive suckling

1. cleaning feeding equipment

2. whole/replacer milk should contain <10,000 CFU/mL bacteria and no coliform contamination

3. use gloves and thoroughly wash hands to reduce pathogen transfer

hygiene for calves includes

1. provide free-choice water

2. especially important in sick calves

characteristics of water and dairy calves

1. introduce around 7d

2. pellets, meal, highly palatable, high-quality protein

3. provide small, fresh amounts daily

considerations for starter (grain) feeding

1. infection such as rotavirus, coronavirus, cryptosporidium, coccidia, E. coli, salmonella, clostridium

2. dietary management such as ingesting dirt or sand

what is related to causing calf scours

1. loss of H20 and electrolytes

2. inflammation of intestines which leads to loss of nutrient absorption ability and ultimately hypoglycemia

what are the concerns associated with scours

1. poor intake due to poor management or intentional restriction

2. poor milk replacer quality is most common cause

3. lack of fat at necropsy can indicate starvation

characteristics of starvation in calves

eating 2-2.5 lb starter/ d consistently for 3 days

what are important parts of weaning criteria

1. gradually reduce milk and feed 1x/d

2. transition to group housing

3. feed ad libitum starter and hay

what is included in the weaning process

1. colostrum timing is critical

2. failure of passive transfer is common

3. nutrition drives rumen development...particularly grain intake

4. starter intake determines weaning success

what are some key takeaways of dairy calf nutrition