The Rumen & effects of changing diet throughout the season

1. The Rumen & effects of changing diet throughout the season http://www.youtube.com/watch?v=_yK-JrLCSUM&feature=player_embedded

2. Rumen

3. RumanMicrobe The large microbe is a type of protist. The creature that looks like a tadpole attached to the side of the protist is a fungal spore. The smaller, rod-shaped beasts lining the underside of the protist are bacteria.

4. Let’s do a little Big Bang Physics • ∆ T core = + Rd +Cd+Cv–Ev+ Hp = 0 • ∆ T core = Body core Temperature • Rd = Radiation (when 2 surfaces of different temperatures) • Cd = Conduction (opposite of insulation) • Cv = Convection (special case of conduction, fluid or wind over a surface) • Ev = Evaporation (heat loss only, cooling when water evaporates off) • ...............humidity can affect • Hp = Heat Production (A chemical process) • The cost to maintain 0-zero is the cost of production

5. Radiation (The flow of heat of 2 non touching objects)

6. Radiation (The flow of heat of 2 non touching objects)

7. Insulation (3 layers) • Itotal = T + Ex + A • I = Insulation • T = Tissue (skin, fat, blood flow/vasodilation & vasoconstriction) • Ex = External (Hair, Fleece, Feathers, Fur) • Highly variable….season, weather • A = Air (Air between hair, fleece, feather, fur) • Rough versus smooth makes a difference (Brahman vs Scotch Highland) • Rain can remove rapidly

8. Did you know? • That sweat dripping off your hat or elbows doesn’t help much • It is the evaporation ( of sweat that cools you down (convection)

9. Evaporation

10. Sweating

11. PantingGood panters move a lot of air without much energy • Good Panters • Dog =Short rapid • Chicken = Flutter • Not so good panters • Cattle lose 3 times more heat by sweating than lungs • Sheep “ 1/8 “ “ “ “ “ “ “

12. How ruminants use energy • Viserca organs- • Liver, GI tract, Heart, Kidney comprise 6% of BW • But use 50% of energy • Muscle41% of BW but only 23% of energy

13. EFFECT OF ENVIRONMENT ON ENERGY REQUIREMENTS Lower Critical Temperature Upper Critical Temperature THERMONEUTRAL ZONE Cold stress Heat Stress Optimum for Performance and Health High Low EFFECTIVE AMBIENT TEMPERATURE

14. Termoneutral Zone

15. Temoneutral Zone

17. Did you know? • How do young lambs and calve survive the cold? • 1. Shelter (out of the wind, south-east/southern exposure) • 2. They have brown fat (1-3 weeks) that makes more energy (heat) than shivering • does not apply to pigs and chickens • A hot ration is cool (due to Heat Increment….heat of fermentation)

19. Effective Temperature Temperature Wind Speed -10 0 10 20 30 Calm -10 0 10 20 30 5 -16 -6 3 13 23 15 -25 -15 -5 4 14 30 -46 -36 -26 -16 -6 *Maintenance Requirements increase .7% for each degree of cold stress.

20. Mud

21. Environmental Effects on Feed Intake Dry, minimum mud Cool night Rain Storm Deep mud Hot night

22. Cow (foregut / pregastric fermenter)

23. Digestion of Forage by Bacteria Digestible Cellulose and Hemicellulose T=0 hrs Digestible Material is Gone Fungal invasion T=6 hrs Undigested Material: Mostly Lignin and Cellulose T=20 hrs Source: Akin, et al. 1993

24. Effects of ambient temperature on digestibility in ruminants • Average decrease in digestibility per ˚C decrease is equal to .18% [NRC, 1981] • Occurs in both ruminant and nonruminant animal species Slide from Gordon Carsten

25. What is going on here? • Intake increases as it gets colder • Thyroxine levels increase which increases motility and constricts rumen areas • Rate of passage and digestibility • Intake decreases at it get hotter • Thyroxine levels decrease and decreases gut motility & feed in gut more time • Rate of passage and digestibility

26. Stage of Forage Maturity vs. Stocker Gains 2.7 2.0 .72

27. Mandan was where Lewis and Clark spent their first winter!

28. 3-year Ohio Study (28 grazing cells) http://ohioline.osu.edu/sc162/sc162_3.html

29. Now lets look at the Forage and TemperatureWithin Season

30. The effect of temperature on the cell wall content (CWC) of grasses of the same maturity (adapted from Van Soest, 1981). • High ambient temperatures bring about rapid rate of maturity of forages • and a rise in cell wall content (CWC)

31. High ambient temperatures bring about rapid rate of maturity of forages and a rise in cell wall content (CWC) and a decrease digestibility of the cell wall (DCW)

32. Light Intensity • High light intensity increases the content of water-soluble carbohydrates • whereas, high temperature decreases water-soluble carbohydrates • When there is heavy cloud cover, such as occurs in the United States during • summer or in tropical areas during the rainy season, both temperature and light • contribute to high Cell Wall Content, which results in lower Digestibility and lowered • intake by grazing ruminants

33. Matching Animal Needs to Pasture Quality Energy 85 Cool season grasses 80 75 70 1200 lb cow* nursing calf or 65 500 lb steer gaining 2.5 lb/d 60 Avg. lactating cow 55 50 Dry, pregnant cows 45 40 Veg. Late Veg. Boot/bud E. bloom Full bloom Hard seed * Superior milking cow

34. Matching Animal Needs to Pasture Quality Crude Protein 25 Cool season grasses 20 15 1000 lb cow* nursing calf or 500 lb steer gaining 2.5 lb/d 10 Dry, pregnant cows 5 0 Veg. Late Veg. Boot/bud E. bloom Full bloom Hard seed * Superior milking cow

35. Lbs. Of Corn ADG Gain Increase F/G 0 1.32 --- --- 1.4 1.75 .43 3.25 2.8 1.75 .43 6.50 4.2 2.00 .68 6.20 General comments of adding grain to forage-based diets In rapidly growing forages, more than 20% of nitrogen in form of NPN Under these circumstances, limited grain could increase nitrogen utilization Above .25% BW, expect reduced efficiency (ie. < 1.5 lb. grain on 600 lb. cattle) Horn and McCollum (1987) have suggested that an energy supplement level that would minimally affect forage intake would be 0.7% of animal body weight. However, level of grain supplementation can vary with forage quality Otimum .2-.5% of body weight? Grain supplementation to steers grazing fescueKentucky ResearchKentu

36. Digestible Fibers

37. Kentucky study: TreatmentCorn/SBM Soyhulls Initial weight 648 629 Supp. Intake/Day 7 7 ADG 1.4 1.8 Studies with readily degradable fiber sources as energy supplements for grazing and forage-fed ruminants have yielded different responses than research with grains. Soybean hulls result in only a small decrease in forage intake. Optimum Rate? 4 pounds? http://beef.osu.edu/library/soyhull.html Grain versus Digestible Fiber Supplementation

38. Since bacteria provide 55% to 80% of the animal’s protein, forages result in less microbial protein per lb. of dry matter consumed than grain diets.

39. Without supplementation, a cow can consume 18 pounds of dry matter from a low-quality forage source. 18 Forage intake without supplementation x 1.25 Increase in forage intake with adequate protein 22.5 Total forage intake with supplementation 0.40 TDN content of the forage x 1.15 Increase in digestibility with adequate protein 0.46 TDN content of forage with supplementation

40. Protein Supplementation • Limited amounts (approximately 1-2 lbs) of high protein supplements (> 30% CP) can be utilized • with low-quality forages. Protein supplementation may increase digestibility and increase forage • intake. • Total pasture crude protein levels may become deficient for stocker cattle my mid-July. Stocker cattle may able to meet their crude protein requirement till mid-August if they are allowed to selectively graze high quality plants. • Therefore, cattle grazing late summer pasture may benefit from protein supplementation. • Supplement containing high levels of protein (>30%) can be fed at a rate of 0.8-1 lb per day or 2.5 lbs fed 3 times per week. If protein supplements contain nonprotein nitrogen, should be fed daily.

41. Metabolizable Protein bypass CP UIP energy (TDN) MP DIP (ammonia) MCP

42. Frequency of feeding • When feeding protein supplement can feed 3 times a week with little effect on performance • Grains and digestible fibers – every day

43. Time of feeding • The time of day will effect affect the amount of forage that the cattle will consume • Cattle have intensive grazing peaks at dawn and dusk, with most grazing occurring in daylight hours • Feeding supplements in the middle of the day may be less disruptive on normal grazing activity and will cause cattle to eat more forage than if supplements are fed early in the morning

44. When ruminants get cold • Energy requirement goes up • Protein Requirements essentially say the same

46. 3-year study NDSU, 2004-2006

47. Evaluating Manure • Great Forage - Between pancake batter and pumpkin pie filling • Low Quality Forage -  Wedding cake (dry and stacked in layers)

48. Water System Requirements

49. FORAGE AVAILABILITY THROUGHOUT THE YEAR

50. Questions ???