1. ANIMAL-RELATED ENVIRONMENTAL ISSUES THAT MAY BE CONTROLLED BY ANIMAL MANAGEMENT Nitrogen Phosphorus Odors Greenhouse gases Sediment Species diversity

2. TOOLS TO MANAGE ANIMAL- RELATED ENVIRONMENTAL ISSUES Nutritional management Managed grazing

3. CONTROLLING NITROGEN EXCRETION BY OPTIMIZING PROTEIN METABOLISM Monogastrics Increase protein digestibility Lower crude protein intake Dietary balance –Protein:energy ratio –Balance of essential amino acids Phenyalanine Valine Tryptophan Threonine Isoleucine Methionine Histidine Arginine Leucine Lysine

4. Increase protein digestibility Decrease N intake Decrease protein degradability Diet balance –Carbohydrate energy –Sulfur –Phosphorus Protein Degraded Escape NH 3 Microbial protein Converted to urea in liver Metabolizable Protein ABSORBEDABSORBED Excreted NPN CONTROLLING NITROGEN EXCRETION BY OPTIMIZING PROTEIN METABOLISM Ruminants

5. MANAGING NITROGEN EXCRETION BY DAIRY COWS 100 cow herd Crude protein, %21.317.1 Protein supplement Soybean meal Heat-treated soybean meal Milk production, lb/day 89.883.188.9 Feed cost, $/cow3.883.623.64 N excretion, lb/yr Urinary25,48717,91416,366 Fecal17,59717,74017,721 Total43,08535,65434,087

6. Lower P intake –Phase feeding Feed phytase to monogastrics –50% of the phosphorus in most feeds is bound to phytic acid Feed low phytate corn and soybeans to monogastrics Dietary balance –Ca:P ratio –Vitamin D metabolites CONTROLLING PHOSPHORUS EXCRETION BY OPTIMIZING NUTRITION

7. MANAGING PHOSPHORUS EXCRETION BY DAIRY COWS 100 cow herd P concentration, %.45.39.36 Milk production, lb/cow 89.890.390.6 $/cow3.883.853.83 Excreted, lb/yr Urinary118108102 Fecal4,5403,5652,992 Total4,6583,6733,094 P balance, g/day+10-7

8. GREENHOUSE GASES Carbon dioxide Methane (CH 4 ) –21 x the greenhouse effects of CO 2 Nitrous oxide –310 x the greenhouse effects of CO 2

9. SOURCE STRENGTHS OF GHG EMISSIONS FROM DIFFERENT BEEF AND DAIRY OPERATIONS U.S. Beef cow- feedlot CA DairyWis DairyNZ Grazing- based Dairy kg carbon dioxide equivalent/kg product Enteric methane 5.5.36.41.60 Manure methane.14.21.03.04 Nitrous oxide 8.1.37.42.76 Carbon dioxide 1.8.33.57.22 Total GHG15.51.261.381.62

10. WHY IS METHANE PRODUCED?

11. CONTROLLING METHANE PRODUCTION BY RUMINANTS THROUGH DIET MANAGEMENT Increase the proportion of grain and decrease the proportion of forage in the diet –Must have a minimum of 50% forage in dairy diets and 10% in feedlot diets Grind forage Feed ionophores –Monensin –Lasalocid –Salinomycin Feed unsaturated fatty acids –Maximum 5% of diet dry matter

12. EFFECTS OF GRAZING ON ENVIRONMENTAL QUALITY Well-managed grazing –Optimize forage productivity and nutritional quality –Maximize forage species diversity –Improve efficiency of forage utilization –Maintains forage cover on streambanks –Minimize soil erosion –Minimize P loading of streams –Minimize soil compaction and trailing –Maximize manure nutrient distribution Poorly managed grazing –Reduced forage productivity and quality –Minimize forage species diversity –Weed infestation –Loss of streambank cover –Stream widening and loss of aquatic habitat –Increased soil erosion –Increased P loading of streams –Increased soil compaction –Increased cow paths –Poor manure distribution

13. KEY TO SUSTAINABILITY OF GRAZING LANDS Managing vegetative cover through –Feed for grazing livestock –Hold soil into place –Filter water –Recycle nutrients

14. EFFECTS OF FORAGE CANOPY HEIGHT ON GROUND COVER, INFILTRATION RATE, AND EROSION RATE AFTER TREADING AT THREE RATES ON A NEW ZEALAND HILL COUNTRY PASTURE

15. COMPONENTS OF GOOD GRAZING MANAGEMENT Appropriate stocking rate –Neither too low or high –Flexible management to maintain forage quality Adjust stocking rate Hay harvest Appropriate rest periods –Based on forage growth rate 15 days early summer 35 days in mid-summer Appropriate design –Number of paddocks 8 – 12 for rest 24 – 36 for grazing efficiency –Square paddocks –Water in each paddock

16. CALCULATING THE LENGTH OF OCCUPANCY FOR PADDOCKS Estimate forage yield Estimate total forage in 5 ac paddock Estimate available forage in paddock Estimate forage intake by fifty 1250 lb cow-calf pairs Calculate days/paddock Calculate total paddocks Calculate total acres 15 cm x 110 lb/ac/cm = 1650 lb/ac 1650 lb/ac x 10 ac = 16,500 lb 16,500 lb x 50% = 8250 lb 50 x 1250 x 3.5% BW = 2188 lb/day 8250 lb/pad / 2188 lb/day = 3.8 days 35 days rest/3.8 days + 1 = 10.2 paddocks 10.2 paddocks x 10 ac/pad = 100 ac

17. FORAGE AVAILABILITY THROUGHOUT THE YEAR

18. ARRANGEMENT OF TREATMENTS (June, 2002)

19. MEASUREMENT OF SEDIMENT AND PHOSPHORUS LOSSES Rainfall simulations Frequency –June, August, October, and April Locations –3 in 2 slope classes within each paddock –3 in each buffer strip at paddock base –3 in each buffer strip 30 ft from paddock base Rainfall rate –2.8 inches/hour Duration –1.5 hours

20. EFFECTS OF FORAGE TREATMENTS ON ANNUAL SEDIMENT FLOW (Year 1)

21. EFFECTS OF FORAGE TREATMENTS ON ANNUAL TOTAL AND SOLUBLE PHOSPHORUS FLOW (Year 1)