Cow Nutrition
Cow Nutrition
Bos Taurus vs Bos Indicus
### Intensive System
Most efficient for young animals.
Timing of feeding:
Weaning: 240 days.
Yearlings: 120 days.
Increases gain and carcass characteristics.
Concerns include:
Acidosis.
Founder.
Liver abscesses.
Comparison with an extensive system, where animals catch up slower due to conditions.
Location of Bunk Line
Not in pen: Quickly becomes muddy and dirty.
Ensure enough bunk space:
Dominant animals may prevent weaker animals from eating.
The Weather
### Windbreaks
Can utilize trees, bales, buildings, etc.
Protects from the wind, reducing snow accumulation.
### Mud
Pulls heat from animals and costs energy.
Requires significant energy for cows to pull themselves out of mud.
Feedlot Management
Mound structures help keep animals out of mud, keeping them drier and warmer.
Bedding provides significant benefits:
Summer: reduces temperature, keeps cooler.
Winter: keeps animals drier and warmer.
Strategic Feedlot Bedding
Improved Average Daily Gain (ADG) when bedding is utilized; animals eat less.
Cheaper than purchasing additional feed.
Shade in Summer
Essential for cooling animals; excessive heat exposure can cause deaths.
Step-Up Rations
Gradually increase concentrates while lowering roughage to allow rumen adaptation.
Concerns in Feedlot Cattle
Limestone
Adds calcium and serves as a buffer.
Can prevent urinary calculi.
Feedlot Diet Composition
Majority consists of corn and forage.
Cellulolytic activity is essential for producing B vitamins, particularly Thiamine, which is necessary to avoid rapid pH drops.
Polioencephalomalacia (PEM)
Linked to low thiamine levels
Additives in Diets:
Heifers - MGA (Melengestrol Acetate)
Prevents cycling in heat, impacting feeding behavior.
Ionophores
Increase production of propionic acid.
Antibiotics
Administered at sub-therapeutic levels to reduce liver abscess incidence.
Buffers
Can be estrogenic, androgenic, or progestagenic; concerns include potential estrogen presence in meat. Phytoestrogens in many foods.
Implants
Impact on growth efficiency.
Cow Nutrition: Dairy Cows
Exam Details
Focus on small ruminants, beef, and dairy.
Important lab schedule outlined (first two weeks at beef center).
Calves and Milk Production
Calf Requirements
Must consume milk, dependent on having had a calf to induce lactation.
Cow Behavior
Stealing calves if they perceive themselves as needing more.
Historically, there was no market for dairy calves.
Dairy Breeds
Breeds include:
Holstein.
Jersey.
Guernsey.
Ayrshire.
Brown Swiss.
Milking Shorthorn.
Animal Genetics and Breeding
Red Holstein Genetics
Double recessive traits, issues of genetic preference for black and white.
Milk Production Record
Record set by a 14-year-old cow producing 123.61 L (32.66 gallons) per day.
Feed to milk ratio of 2.75-3.17 lb of feed per liter of milk.
Cow/Calf Nutrition
Management Practices and Key Points
Roughage management is crucial for beef cows.
Traditional practices may lead to overfeeding in late gestation and underfeeding during lactation.
Calving seasons influenced by culture and demand; need to balance nutrient availability across seasons.
Ruminant Nutrition Principles
Calving Season Management
Categories include:
Winter: calves born in January-February, wean by summer grazing.
Spring: calves born in March-April; benefits from winter nutrition.
Fall: calves born in September-October; reliance on summer pasture.
Animal Adaptation
Manage forage and supplements based on environment and conditions.
Breed Characteristics
Simmental (Bos Taurus): Early sexual maturity and good fertility.
Brahman (Bos Indicus): Heat tolerance and maternal efficiency.
Use crossbreeding for benefits like increased carcass size and heat tolerance.
Transition and Growth in Feeding
Provide adequate nitrogen due to rumen bacteria needs.
Importance of seasonal grass cycles and grazing practices.
Health Considerations in Ruminants
Broket Disease
Pulmonary hypertension and pulmonary edema, often related to high-altitude grazing.
Pap Test
Measurement of pulmonary arterial pressure via catheterization.
Dairy Cow Advances and Systems
Milking Technology
Use of robotic milking systems allows for cows to be milked without human intervention, increasing convenience.
Impact of diets on milk quality; New Zealand systems favor grass-fed without grain leading to unique milk characteristics.
Regulatory compliance in organic dairy systems.
Sheep Nutrition
Parasite Management
Challenges of managing sheep under harsh weather conditions.
Historical Context
Insights into sheep's roles and impacts; e.g., Navajo churro conservation efforts.
Nutritional Management of Small Ruminants
Importance of managing condition scores and feeding strategies to avoid obesity.
Use of exercise and varied feeding locations to promote health and prevent complications.
Conclusion
Focus on body condition scores and nutritional management throughout life stages is critical for optimal performance and reproduction in bovine and small ruminant systems.