Dairy Mgt: Nutrient requirements and rumen development (3)

What pasteurization system do we have at our MAFES creamery?

They have both HTST and vat or LTLT pasteurizers.

High-Temperature Short-Time pasteurization: 161.6°F for 15 seconds;

LTLT (Low-Temperature Long-Time): 145°F for 30 min

Rumen Development

-Within a few days of birth, the calf's rumen begins to develop a population of microbes.

-The number and types of bacteria are a function of the types of feeds the calf eats.

-The esophageal groove does not function when the calf eats dry feeds; they enter the rumen, where they must be digested by microbes or chewed further by rumination.

-In addition to feeds, the environment, bedding, and hair provide microorganisms that inoculate the calf's rumen.

-Rumen microbes require water to grow properly and ferment feedstuffs. If water is not provided to the calf early in life, rumen microbial growth is limited.

There are two separate components to rumen development.

1 physical size of the organ

2 elongation of rumen papillae and thickening of rumen walls

-Comparison of rumen papillae development at 6 weeks in calves FED...

-The lining of the rumen wall in an adult cow has a very pronounced covering of papillae. These papillae are finger-like projections that greatly increase rumen surface area, the area through which nutrients can be absorbed.

-Papillae development is stimulated by the end products of microbial fermentation, specifically butyric acid and, to a lesser extent, propionic acid.-

-Grain-fed calves have a tremendous amount of rumen development at an early age — 3 to 4 weeks.

-Early rumen development= earlier weaning! That is why we feed grain early.

Nutrient Requirements

-The amounts of protein and energy required by a calf are divided into two categories based on their use for maintenance (NEm) and growth (NEg).

-Maintenance describes the amount of energy and protein needed to support normal bodily functions, including maintaining body temperature.

-Maintenance requirements are related to body size;

-Protein provides amino acids used to build body tissues.

-A newborn calf has few digestive enzymes, and it cannot utilize most vegetable proteins as well as it utilizes milk proteins.

-Energy is used to support body functions and allow dietary protein to be used in building body tissue.

-The major sources of energy for the newborn should be derived primarily

from lactose (milk sugar) and highly digestible fat.

-Environmental conditions also affect maintenance requirements.

- Calves housed in drafty, wet conditions have more maintenance energy needs than those housed in draft-free, dry environments.

- Extremely cold or hot weather also increases energy needs.

-Nutrients needed to support growth logically increase as growth rate increases.

Liquid Feeds - Milk Replacer

-Approximately half of the dairy calves in the United States are fed milk replacer for most or all of their liquid feeding period.

-The most important items to identify are the crude protein and fat content, ingredients, and feeding instructions.

-Differences in the price of milk replacer are due to ingredient selection, manufacturing technology, and nutritional quality

Liquid Feeds - Waste Milk 

-Milk from treated cows should only be used to feed calves raised for herd replacements or those kept for eight to 12 weeks after the last feeding of such milk.

-Do not feed calves waste milk that is watery or that comes from quarters showing signs of severe mastitis, from cows with an elevated temperature, or from cows shortly after they have been treated with antibiotics.

-Calves that suck each other immediately after drinking mastitic milk may actually inoculate the immature teats and eventually cause heifer mastitis.

-Day-to-day variability of waste milk may contribute to scours and poor growth in young calves.

-PASTEURIZATION does not remove out antibiotics

Milk replacer feed at __ % body weight BW

12%

Whole and Waste milk feed at ___% body weight BW

10%

Whole milk = ___ solids content or dry matter

12.5 - 13%

Ideal daily gain: 1-4 weeks > 1 lb/d

5-8 weeks ≥ 1.8 lb but not > 2lb

Liquid feed-Water 

Increase water intake increases the amount of grain intake 

Dry Feed

-The preweaned calf requires both liquid and dry feeds and should be offered a dry grain mix by 3 days of age.

-Adequate, early intake of dry feed is important because dry grain stimulates rumen development. palatable to encourage intake

-Gain buckets need to be emptied and refilled one or two times each day, especially during hot weather

Dry Feed- Less processed can have ___

More starch (30-40%)

Dry feed-More processed should ____

Not have more than 25% starch 

Should we feed forage to calves? 

Yes around day 49 during weaning to prevent acidosis but cows grain intake houd be more than its hay intake 

But not before 6 weeks and can depend on weaning system being used

Calves have limited space in their digestive tracts and bulky forages quickly fill this space, sending a signal to the brain that depresses appetite.

___of rumen papillae (caused by excess of fermented feed)

Hyperkeratosis

Feed forage to prevent acidosis

Feeding program and Weaning 0-4d

Colostrum and water 

Around day 3 calf starts grain (stays on grain throughout weaning) 

Feeding program and Weaning 1 week

Whole milk 10%BW

Milk replacer 12%BW

Feeding program and Weaning 2- 5weeks

Gradually increase to 2 gallons a day 

Feeding program and Weaning 6 weeks 

Gradually DECREASE to 1 gallons a day 

About half way through week 6 start calf on hay/forage

Feeding program and Weaning 7-8 weeks

0.5 gallons a day 

Weaning

Grain intake approximately 3lb/day for 3 consecutive days

Maintain calves in the same environment for at least ___ after weaning. When moving them to group pens at ___ weeks of age, most calves should be consuming _____

1 week 

9-10 weeks 

4-5 of grain per day 

Abrupt changes will increase the likelihood of nutritional scours and stress.

Feeding program and Early Weaning- 0-4d

Colostrum and water 

Around day 3 calf starts grain (stays on grain throughout weaning) 

05 grain/day for 4 weeks or 1lb/2 days for 2 weeks

Feeding program and Early Weaning- 1-3 weeks

2 gallons per day

Feeding program and Early Weaning- 4-5 weeks

Gradually DECREASE to 1 gallons (8 lb) calf/DAY

Early Wearing 

Grain intake approximately 2-3lb/day for 3 consecutive days

early weaning

Early Weaning 

Maintain calves in the same environment for at least ____ after weaning. When moving them to group pens at___ of age, most calves should be consuming _____

1 week

7-8 weeks of age

4-5 lbs of grain per day 

Ruman development is stimulated by the end products of microbial fermentation specifically ____ and to a lesser extend ____

Butyric acid

propionic acid 

The early intake of ___ is important for rumen development 

Dry feed

Waste Milk is why we have___

Antibiotic resistance since the calf drinks milk that cant be sold (ex mastitis milk) where cow have been given antibiotics