Pasture-based nutrition considerations for horses Dr. Gary Heusner

Extension Bulletin 1224 Forage Systems for Horses in Georgia 1. ps/forageshttp://commodities.caes.uga.edu/fieldcro ps/forages 2.Forage Extension Publications

Master Equine Management Training

12 hrs in daylight 12 hrs at night 24 hrs in pasture Time grazing Percent of avail time

Horse Diet Basics 1.Water intake 2.Maximize forage intake 3.Minimize concentrate consumption 4.Balance the ration in the following order (a)energy (b) protein (c) minerals (d) vitamins 5. Monitor body weight & body condition score

Horse diet basics (cont) 6. Change feedstuffs gradually (7-14 days) 7. Calcium to phosphorus should be between 3:1 to 1:1 8. Supplement minerals & vitamins 9. Feed each horse as an individual

ENERGY Carbohydrates CHO Fats CHO Calories Digestible energy Megacalories per day i.e pound horse requires 16.4 mcals/day digestible energy ratios key to proper diet formulation

Energy intake Determining adequacy? Weight body condition scoring general health behavior how much in feed?

Body Condition Score

Minimum Body Condition Score 5 MODERATE Back level. Ribs cannot be visually distinguished but can be easily felt. Fat around tail head beginning to feel spongy. Withers appear rounded over spinous processes. Shoulders and neck blend smoothly into body.

BC 4.5

BC 5.5

Master Equine Management Training

Things to Consider When Choosing a “Base” Horse Forage Perennials should form foundation of grazing system – Dependable! – Persistent – Productive – Dependable Think about climate and timing of production Horses grazing tall fescue/bermudagrass near Athens GA

Cautions (forages to avoid) High endophyte fescue Broodmares, young growing horses Sudangrass & Sorghum X Sudan hybrids and Johnsongrass cystitis, prussic acid Annual clovers will not eat

Warm Season Perennials All base forages should be perennials! Warm season plants produce in summer months Late April – first frost Very drought tolerant and most are grazing and treading tolerant Bahiagrass and Bermudagrass

Hybrid Bermudagrass Must be established vegetatively 1.Slow 2. Expensive 3. Small acreage contracting difficult Benefits 1.Higher yields 2.Good quality 3.Possible hay production varieties = Coastal, Russell, Tifton 85

Seeded Bermudagrass Common bermudagrass can be a good choice for pastures! – Dense sod – Good quality – Yields approximately 60-70% of hybrids Cheyenne – Excellent alternative to common and hybrids – Yields approach Coastal – Weed problems at establishment – ~$80 per acre seed cost Giant – Does not survive more than one or two years!!! Currently looking at several alternatives for Georgia

Cool Season Perennial Grasses Tall fescue is most persistent and productive species for this area Orchardgrass will persist in this area for 2 years under grazing – Less productive in fall than tall fescue Timothy and KY Bluegrass are NOT an option Tall fescue

Signs of Fescue Toxicosis in the Horse  fertility  fertility Pre-mature placental separations Pre-mature placental separations Prolonged pregnancy (avg. 27 days past) Prolonged pregnancy (avg. 27 days past) Foaling difficulty (dystocia) Foaling difficulty (dystocia)  placental retention  placental retention Agalactia or low milk production Agalactia or low milk production Low IgG levels in colostrum Low IgG levels in colostrum

Warm Season Annuals Crabgrass is probably best warm season annual pasture for horses – Can be used in combination with tall fescue Millets can be grazed with horses but are difficult to manage Sorghums should be avoided due to urinary cystitis problems (johnsongrass, sorghum- sudan, sudangrass) Crabgrass

Cool Season Annual Grasses Best utilized as a complimentary species Perform well in dormant bermudagrass pastures – Wheat – Oats – Annual ryegrass Broadcasting lbs/ac of annual ryegrass on closely grazed bermudagrass is economical and effective Do not overseed annual grasses into tall fescue Annual ryegrass + white clover sod seeded in dormant bermudagrass

Forage Intake CLASS OF HORSEDAILY FEED INTAKE (% OF BODY WEIGHT) RELATIVE FORAGE QUALITY (RFQ) Maintenance %75 or greater Gestating mare %80 or greater Lactation %90 or greater Growing (weanlings) %100 or greater Work (performing) % 100 or greater Stallions (non breeding) %75 or greater Stallions breeding %80 or greater

Lbs of grain/100 lbs Body Weight Total Air Dry Feed Consumption % of Body Weight * Type of WorkRate of Growth Physiological Function NoneMaintenance First 2/3 of gestation Light a Slow Last 1/3 of gestation Moderate b Medium Lactating mare, Stallion in service Heavy c Fast Lactating mare in drylot Very heavy d __ * On an AS FED BASIS approximately 90% dry matter a Light work defined as 1 to 3 hours per week average heart rate 80 bpm b Moderate work defined as 3 to 5 hours per week average heart rate 90 bpm c Heavy work defined as 4 to 5 hours per week average heart rate 110 bpm d Very Heavy work various; ranges from 1 hour per week speed work to 6-12 hours per week slow work, heart rate 110 – 150 bpm INTAKE OF GRAIN ACCORDING TO TYPE OF WORK OR PHYSIOLOGICAL FUNCTION

Summary Horses were designed to be grazers. Properly managed pastures provide the ideal source of nutrients. Pastures provide for exercise and better health conditions. Manage pastures as in a “growing and harvesting” mode.