This document discusses cattle nutrition and feeding strategies across different phases of production. It covers the nutritional needs and feeding programs for dairy cattle in their lactation cycle and beef cattle in their biological cycle. Key points addressed include the nutrient requirements and common feeding practices for cattle in growth, gestation, lactation and dry periods. Various grazing systems and some nutritional disorders affecting cattle are also summarized.

1. Cattle NutritionRuminant HerbivoresCalf- young animalHeifer- female calf that has not given birth and is less than 30 months oldCow- older than 30 months old, or has given birthBull- intact maleSteer- castrated male up to 4 years oldOx- castrated male, more than 4 years old

2. Dairy CattleMain objective- increase dry matter intake to produce higher levels of milk productionKey factors: energy, ration digestibility, rumen fill, palatability, body weight( BCS), environment, frequency of feeding and water

3. Phase feeding programPhase feedingChanging the nutrient concentration in a series of diets formulated to meet an animal’s nutrient requirements more precisely at a particular stage of growth or production

4. Based on lactation and gestation cyclePhase 1First 10 weeks of lactationPeak milk production happens in this phaseNegative energy balance develops, so cow uses body stores to make up difference ( can borrow fat, but cannot borrow protein)

5. What to feed in Phase 1Increased grain for energy ( corn, wheat, soybeans)Protein supplementation to meet amino acid requirements ( dried brewers grain, distillers grain, corn gluten meal)Increased concentrates and fats to increase energy density of feed ( soybeans, sunflower seeds)Sodium bicarbonate “ buffer” to reduce acidosis and maintain ruminal ph

6. Phase 2Begins 10 weeks post calving and can continue to 20th weekHighest dry matter intake happens hereNutrient intake is finally in balance with nutrient needs

7. What to feed in Phase 2Lower protein levels because requirement is met by supplementation in Phase 1Adequate fiberLimited grain intakeFrequent feeding ( minimizes digestive upset)

8. Phase 3 “late lactation period”, cow is pregnant againNutrient intake exceeds requirement for productionMain period for restoring body reserves for next lactation

9. What to feed in Phase 2Easiest phase to manage because cow is pregnant and milk production is decliningIncreased amount of forage instead of concentratesLower protein

10. Phase 4Most of the “ dry” periodFinal regaining of any lost body weight happens hereGoal is to get cow in good condition for parturition, but not excessively fat ( BCS of 3.5 out of 5.O scale)

11. What to feed in Phase 4High protein, energy, Ca and P needsCombination of legume-grass hay and corn silage ( with added vitamins and P0Long stem grass hay ( length of hay matters)Limit grain to energy and protein needs

12. Body Condition ScoringA numeric system to subjectively assess and animal’s degree of fatnessFat Cow SyndromeHigh blood lipids and fatty liver from eating excess energy from grain or corn silage

13. Can lead to calving difficulties, displaced abomassum and ketosisPhase 5Last 1-3 weeks of “dry” period, just before calvingReferred to as a “transition period”Increase grain intake to prepare rumen for high energy diets that will be needed postpartum

14. What to feed in Phase 5Gradual increase in grainsSmall amounts of all ingredients used in the lactation rationMaybe decrease Ca in “ milk fever” prone cows

15. Beef Cattle NutritionMost critical factor influencing performance of cattle on forage diet is the amount of Dry Matter IntakeYoung, growing grass and pasture crops usually have ample nutrientsold pastures, crop residues and harvesting methods cause reduction in nutrients

16. Biological CycleGoal: optimal nutrition at each stage, not maximum nutritionCycle is made up of 4 periods that span 1 year: 3 trimesters and 1 postpartum period

17. First Trimester ( 95 days)Begins the 1st day of conceptionNutrient needs are for maintenance and lactation if the cow has a calf with her Milk production is declining at this stage

18. Second Trimester ( 95 days)Calf is weaned, lactation requirements endLowest nutrient requirements at this pointFeed minimally Easiest and most economical time to increase a thin cows BCS

19. Third Trimester ( 95 days)Rapid fetal growth causes rapidly increasing nutrient needsWatch BCS carefully, cow gains 1 lb per dayToo thin cows experience dystocias, weak calves and decreased milk production

20. Postpartum Period ( 80 days)High lactation requirementsFeed intake is 35-50% higher than non-lactating cowNutritional stress at this point causes problems during the cow’s next breeding ( usually 80 days post partum)

21. Energy RequirementEnergy is considered first in balancing diet for beef cattle, it’s the largest portion of the rationEnergy utilization determines cow’s ability to use other nutrientsGood quality forage satisfies adult energy requirementsPoor quality forages need to be supplemented with concentrates

22. Protein Requirements50% of all protein and amino acid needs are met by microbial protein synthesisProtein deficiency is common when cows consume straw and low quality hayUrea is commonly used as a protein supplement

23. Beef Cattle, Water requirementsNeed abundant supply at once dailyRange cows consume 2 ½ gallons daily in winter and up to 12 gallons per head in summerWhen salt is added, water need is increasedFresh succulent feeds or silage help reduce need

24. Beef Cattle mineral requirementsSalt- need more when eating succulent forages than when eating drier forageCalcium- depends of Ca concentration in soil, higher needs in growing and lactating cowsPhosphorus- Low P levels in roughage, so P is often offered free choice in a mineral mixCobalt- required for rumen microorganisms to synthesize vitamin B 12

25. Minerals continuedCopper- Simental and Charlois have a higher requirement than AngusIodine- deficiencies in Northwest and Great Lakes area soil; supply via iodized salt

26. Beef Cattle Vitamin RequirementsC, D, E, K and B complex- no need for supplementation; ruminalmicroflora synthesizes B complex and K, Vitamin C is synthesized in tissues, Sun dried forages contain lots of Vit D and EA- roughage and grains are low in Vit A, causing a deficiency. Cattle on pasture can store large amounts of Vit A for 2 months in liver, so deficiency isn’t immediately apparent. Look for signs of rough coat, diarrhea, excessive lacrimation

27. Grazing Systems and ManagementContinuous GrazingMost common type of grazing scheme

28. Cow grazes 1 area for the entire season up to 1 year

29. Low maintenance, but production suffersGrazing systems continued2. Deferred rotational grazing4 pasture system

30. 1 pasture would not be grazed from spring to mid summer in order to allow desirable plants to flower and reach seed maturity

31. The following year another pasture would not be grazed

32. After 4 years, all four pastures will have had time to restGrazing systems continued3. Rest rotationUses 3-5 pastures

33. 1 pasture is not grazed for an entire year, while herd uses other pasturesGrazing Systems continued4. Short duration grazingDeveloped in France

34. 8-40 pastures grazed intensively for 2-3 days, then not grazed again for several weeksNutritional DisordersPasture bloatComes from consuming lush legumes ( alfalfa, red clover)

35. Relieve bloat by inserting stomach tube into rumen and giving anti-foam material ( ex vegetable oil)

36. A trocar is used in extreme cases to release pressure ( large “needle” puncture through skin and gas rushes out)Nutritional disorders continuedGrass tetanyLow Mg levels in blood from grazing lush green grass pastures

37. Common in cows nursing calves under 2 months

38. Symptoms: excitability, cows act blind

39. Fix by feeding free choice mineral supplement containing Mg, early in grazing seasonNitrite toxicityCaused when intake of nitrite is in excess of the rumen’s ability to convert it to ammonia

40. Causes hemoglobin in blood to change into a form which cannot transport oxygen to the tissues

41. Cow dies from asphyxiation

42. Treat with injection of IV methylene blueFescue toxicityCaused by grazing or consuming harvested hay from tall fescue pastures

43. Cow eats the endophytic fungus that grows between the fescue cells

44. signs: soreness in hind limbs, “ fescue foot” hooves and tail slough off, hypersalivation and polyuriaAcute Pulmonary Emphysema “ Asthma’Occurs in western US when cattle are moved from dry rangelands to lush meadow pastures abruptly

45. Signs seen in 4-5 days after diet change

46. Symptoms: labored breathing, extended neck, open mouth breathing, grunting

47. Prevention: ( no treatment) slowly introduce cattle to new pasture and supplement with monensin