Nutrition for the Cow Herd

1. Nutrition for the Cow Herd Grazing Season Winter Feeding – large portion of the annual nutrient cost Strategy: Maximize length of the grazing season Try to be economical during winter feeding

2. Principles of Cow Nutrition – Emphasis on Winter Feeding Proper nutrition of the wintering cow is a necessary evil – important to the cow but expensive Spring calving cows are in late gestation and early lactation – most critical times of the annual cycle

3. Principles of Cow Nutrition – Emphasis on Winter Feeding Nothing you will do will impact current and subsequent calf crops more than proper winter nutrition Can not afford to obtain maximal (100% calf crop; need to find the optimal (90-92%)

4. If winter feeding for 100 days of gestation and 70 days post partum: 100 days * $.92/day = $92 70 days * $1.14/day = $79.80 Total = $171.80 – these costs do not include labor or feeding equipment 510 lb WW, 88% calf crop = 449 lb wean/cow 449 lb x $1.15 (avg for steers and heifers) = $516 Winter feed cost are 35-40% of your gross revenue!

5. Nutrients all animals require: *** Energy *** Protein Minerals Vitamins Water No nutrient is more important than another, but energy and protein are: Most costly to provide Most likely to affect production

6. Minerals Macro-minerals: Ca, P, Mg, K, Na, Cl, S Micro-minerals (trace minerals): Cu, Se, Zn, Mn, Fe, I, Fl, Co, Cr, Mo, S Forms: Oxides Sulfates and carbonates Proteinated: Zn, Cu, Mn, Fe, Se

7. Minerals – Calcium and PhosphorusMajor components of milk Forages are good source of Ca, especially legumes (alfalfa) Ca is inexpensive to supplement: ground limestone, must be pulverized Forages maybe deficient, some supplementation may be necessary in the winter Mineral supplements with 5% P will be adequate P sources are expensive and will make the mineral supplement more expensive than it often needs to be Environmental concern??

8. Minerals – MagnesiumLook out for Grass Tetany Grass tetany is a Mg deficiency usual observed in the spring – early turn-out Usually some death loss Cool soils, rapidly growing cool-season grasses results in low uptake of Mg and diluted Mg in vegetation Often is a result of high K in forages as much as low Mg – causes an imbalance and poor metabolism of Mg desire K:(Mg + Ca) < 2.3 in grazed forage Keep Mg oxide in your mineral supplement – I like it year-round!

10. Minerals – CopperLots of Cu deficiency in the West Geological Cu deficiency – leads to deficiency in the grazed forage More often there is a Mo abundance – antagonist to Cu Want a Cu:Mo ratio in vegetation greater than 7 Also, S (sulfates) are Cu antagonists! Deficiency hard to diagnose, may be just poor growth, rough hair coat, etc Blood test is not a good indicator – need liver sample! May justify expense of proteinated Cu

11. Minerals – SeleniumLots of Se deficiency in the West Geological Se deficiency – leads to deficiency in the grazed forage FDA regulates the level allowed in supplement to .3 ppm in the diet –historical evidence that Se is carcinogen but the reality is it is not a cancer risk Deficiency symptoms are common White muscle disease Weak calves, fail to thrive and die Slough hooves (also symptom of excess SE) Retained placneta Recommend dietary Se Boluses and injectables (Bo-Se) are okay but don’t solve the problem May justify expense of proteinated Se – recently FDA approved seleno-methionine

12. Vitamins Not B vitamins, C and K – why not? Vitamin A Abundant in green forage Liver (adipose tissue) storage for 90 days Watch out after months of feeding low quality forage in the winter Restore vitamin A 30 days pre-partem Vitamin E Also in green forage Very labile – easily destroyed, not present in: Year-old hay Silages Spoiled feeds Body stores don’t last as long May improve immunity of the newborn calf Especially important if in Se-deficient area

17. What about using fats to meet the dietary requirement of the cow? Fiber (forage) and starch (grain) are more typical substrates for energy for the beef cow Fats usually have higher $/Mcal! But, fats, especially PUFAs, may have metabolic and/or ovarian benefits for the PP cow Fish oils Vegetable oils (cottonseed, canola) Watch out for negative effects on the rumen

18. Protein

19. Protein is Required by Cows to: 1. Enhance feed intake & use of energy 2. Supply nitrogen to microbes - Ammonia - Amino acids - Peptides 3. Supply amino acids for synthesis of: - Milk protein - Tissue protein - Enzymes, hormones, etc. 4. Supply carbons for glucose synthesis

20. Crude protein (CP) (TP) + (NPN) true protein + non-protein nitrogen Feed protein 16% N 6.25 * N = CP of feed urea is 287% CP 45.92% N * 6.25

24. How much of an cow’s CP requirement can be provided by urea?? $64,000 question!! Very depend on energy of the cow’s winter ration Most urea provided in pelleted, dry supplement or a liquid supplement: How much energy is in the basal ingredients? How much energy is in the supplements? Grain and grain by-products in the dry supplements, molasses in the liquid supplements Hunt says urea can be: 1/3 of cow’s protein reqmt, or ½ of protein in the supplement

26. “Project $1.5 M” Approximately 500,000 beef cows in Idaho What if I could help reduce the winter feeding cost on 1/3 of these cows 150,000 cows x $10 = $1.5 M!! Help producers change the way they think Instead of thinking lbs of hay fed/day, think of lbs of protein and calories of energy Instead of thinking $/ton of feed, think $/protein and $/calorie of energy

27. My strategies for keeping winter feed costs low have been: Wintering Alternative I: More energy and protein from concentrates, less from forage Wintering Alternative II: Ammoniation of Low Quality Forage What to do? Go back to the basics – look for feeds with lowest cost of energy ($/Mcal) and protein ($/lb of protein)

28. Wintering Alternative I: More nutrients from concentrates, less from forage Energy from concentrates has been cheaper than forage: Feeder alfalfa or grass hay @ $120/ton, .78 Mcal/lb = $.077/Mcal Corn @ $200/ton, 1.35 Mcal/lb = $.074/mcal Two methods to economize: Restrict/limit feed hay Fill up on low-quality roughage – straw If possible, let the cow do the harvesting!

29. Wintering Alternative II: Ammoniation of Low Quality Forage Swells “cracks” fiber to provide better ruminal microbial attack Provides a source of nitrogen for microbes to convert to protein Agents for ammoniation: *** Anhydrous ammonia Aqueous ammonia Urea

30. Nutritive value of bluegrass straw needs to be enhanced to support a productive beef cow

32. Daily feed cost for 1000 lb, late gestation cow Untreated bluegrass straw Straw ($75/ton) = 15.4 lb Barley ($200/ton) = 7.5 lb Alfalfa hay ($120/ton) = 5.1 lb $/day = $1.63 Ammoniated bluegrass straw Straw ($100/ton = 18.9 lb Barley ($200) = 2.6 lb $/day = $1.21, or Instead of $25, could afford $70/ton) treatment cost

33. Factors affect ammoniation response:Can we reduce the amount of ammonia need or increase the digestibility response? Bale with some moisture - 18% moisture such as dew moisture or after a light rain Ammoniate in early fall when ambient temperatures of still warm

34. Wintering Alternative III: By-product feeding Food or industrial by-product – utilize ruminal digestive system Moisture content may limits distance to transport – often regional resources Grain byproducts: distillers grains (!), wheat millrun, grain dust, screenings, etc Cull peas or screenings!! Grass seed byproduct Food by-products: potato, apple pomace, onions, carrots, beet pulp (wet or dry) Many, many others depending on the region