Profiling Nutritional Status of Grazing Bison: Using NIRS Fecal Profiling Technology Dr. Jerry W. Stuth Kelleher Professor GANLAB Dept.

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1 Profiling Nutritional Status of Grazing Bison: Using NIRS Fecal Profiling Technology Dr. Jerry W. Stuth Kelleher Professor GANLAB Dept. Rangeland Ecology & Management Texas A&M University

2 Fundemental Issues in Using the NIRS/NUTBAL 1. Can we devise a sex, age, weight and body condition score that is tied to a frame scoring system to set a standard reference weight? 2. How much genetic variability do we need to recognize a. Affects frame score b. Affects milk yield c. Affects energy requirements d. Selection away from cattle genes in foundation herds? e. Woods vs Plains Woods are 15% larger considered more pure..is it effect of environment? 3. What is peak milk yield and when does it occur and is there a 16-week lag in fecal output. 4. Does NUTBAL environmental module for cattle work for bison? 5. Do bison decrease intake in late pregnancy like cattle? 6. Does fecal NIRS diet quality estimates for cattle work for bison? 7. How much of our pregnancy testing, mineral and parasite NIRS profiling technology can be directly used on bison?

3 Pregnancy Rate (%) Body Condition Score Calving Breeding Weaning

4 Calving Interval (days) Body Condition Score (1-9 system)

5 Backbone Vertebrae Transverse Process (shortribs) Sublumbar Fossa Hooks Tailhead Trochanter major Pins Ribcage 12th/13th Ribs

6 BCS 6-

7 BCS 5+

8 BCS 4

9 BCS 3

10 Bison skeleton

11 Bison Cattle Transverse Process (shortribs) Backbone Vertebrae Sublumbar Fossa Hooks Tailhead Trochanter major Pins Ribcage 12th/13th Ribs

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15 Can we use the U-V effect, last 2 ribs, transverse process, tail head fat and distinction of back bone for body condition scoring? can we see it in winter with full coat? If so, we must weigh, measure hip height, age and sex the animal to a set body condition scoring standard to build a standard reference weight of the animal.

16 NIRS Near Infrared Reflectance Spectroscopy light passing through the bonds or electrical field between atoms, eg. carbon, hydrogen, nitrogen, will cause excitation of the electrical field causing some parts of the near infrared band to be either absorbed or reflected resulting in differential reflectance patterns given the composition of chemical bonds within the sample. No compounds are 0.1 measured. NIR Spectra C=H nm 2500 nm

17 Fecal Chemistry =CH2, =CH3, =C=O=C=, Amide, Amine, Aromatics, Protein Bonds, Peroxides, =CH3-N, Alphatics Diet Quality Crude Protein Dig. Org. Matter Phosphorus, etc DIET:FECAL PAIRS 0.1 NIR Spectra Predicted Diet Crude Protein Digestible Organic Matter Phosphorus, etc = Waveform transformation and statistical analysis is used to create a calibration equation to predict components

18 Fecal NIR spectra from cattle grazing high vs low quality Bermudagrass st Derivative Log 1/R October 1998 CP 13.59% DOM 63.30% February 1999 CP 6.26% DOM 58.16% Wavelength, nm

19 Intake of Bison compared to Herefords fed the same feed y = x R 2 = 0.86 SEy = Outlier Bison Intake (%BWT) Cattle Intake (%BWT)

20 Bison are subject to photoperiod responses independent of nutrition * Daylength affects the pineal gland the near base of the brain * Pineal gland produces melatonin which inhibits growth hormone and thyroxin (a metabolism regulating hormon) - High levels of melatonin suppress these hormones reduces intake due to reduced metabolism - Short day length increases melatonin levels and suppresses fecal output (decreases intake)

21 Bison Females (12-16mo) 249 kg (548 lb) Intake Adjustment Oct Nov Dec Jan Feb Mar Apr May Day of Year

22 Effects of Photoperiod on Intake of Young Bison Females Consuming Hay of a Constant Value 16m 12m 1.15 Intake Adjustment Winter Solstice Oct Nov Dec Jan Feb Mar Apr May Day of Year

23 Photoperiod Adjustment for Bison Fecal Output Factor Intake Adjustment Factor Day of Year

24 Metabolic Fill Method for Determining Daily Dry Matter Intake Voluntary Intake (kg DM/d) = Fecal output (kg DM/d) Diet Indigestible Fraction (kg IDM/kg DM where Diet IDM = 1 - (TDN% *.01) TDN = DOM * /(1-.6)= 10/.4 = 25lb/d NUTBAL PRO models dynamics of fecal output while the NIRS fecal profiling system provides the digestible organic matter percent (DOM) to derive total digestible nutrients (TDN).

25 Fecal output (kg DM/d) Voluntary Intake (kg DM/d) = Diet Indigestible Fraction (kg IDM/kg DM Factors Affecting Fecal Output Dynamics * Baseline fecal output for each species and puberty status * Milk production and stage of lactation * Stage of gestation (pregnancy) * Breed variation in terms of gut capacity * Thermal stress (max/min temperature, humidity, wind, sun) * Conditions of coat (wet, muddy) * Night penning practices * Grazing pressure and forage availability * Effects of feed grains (associative effects) * Metabolic modifiers used (ionophores, implants, feed additives) * Internal and external parasites

26 There is a high correlation between intake and digestibility but it is not predictive of intake due to a wide array of other factors that affect intake, eg. Temperature, physiology, parasites Intake (% BWT) High starch diets from grain Digestibility (%)

27 Frame Scores can be derived from hip height across the hooks HIP HEIGHT

28 Body Weight and Height of Cattle of Different Frame Scores (by age class) Inches/Pounds Basis days 420 days Mature Frame Height Weight Height Weight Height Weight BISON Mature Weight FEMALE lb MALE lb

29 Standard Reference Weight = that weight of the animal at average fatness (BCS= 5, 1-9 system). It is used to calculate requirements. If BCS > 5 then SRWt = Body weight/( (.0898 * BCS) If BCS < 5 then SRWt = Body weight/( (.0657 * BCS) Factor Body Condition Score (1-9)

30 To grow microbes in the rumen you must have nitrogen to form NH4 and matching carbon skeletons to convert to protein and energy. NH4 C:N Weight Loss Zone C:N Reduce Weight Gain Production Zone 4 DOM/CP 8 C:n

31 Growing animals below their puberty threshold intake drive is strongly influenced by the ratio of energy to protein or DOM/CP due to changing prioritization of protein and energy during growth. Optimum fermentation occurs at a DOM/CP ratio of 4. (85/64 ºF, 5 mph wind, 50% humidity) Fecal Output Factor DOM/CP Ratio

32 Impact of low DOM/CP ratios on fecal output resulting in high ammonia levels in the blood, increased requirements to convert it to urea and excrete it in urine and reduced appetite drive. Example below is for a 608 lb, 10 month old steer. (85/64 ºF, 5 mph wind, 50% humidity) Fecal Output Factor DOM/CP

33 Fecal output is suppressed after day 172 of pregnancy or 5.5 months. Primary mechanism is physical rumen volume displacement. % decrease to fecal output factor Bison average gestation period is 270 days Birth weight of a bison calves is Females 55 lb Males 66 lb Days Pregnant

34 Lactation is about 210 days or 7 months

35 Milk production normally peaks at approximately 45 days varying on breed and nutritional plane of the animal. Fecal output rises with increasing milk production but peaks about 16 weeks after the peak milk production is attained. Mechanism seems to be hormone feedback on gut capacity and intake drive wk Fecal Output (lb/d) Milk Yield (lb/d) Day of Lactation 6 Feces Milk

36 When there is a deficit of Metabolizable Energy, based on the breed attribute, milk production will be reduced depending on the stage of lactation. Early lactation is less sensitive to energy deficiencies than late lactation. This is breed dependent Milk yield/potential yield Early Lactation Late Lactation ME available for milk/me needed for potential yield

37 1.5 SPRING Bison Energy Req. Adjustment SUMMER FALL WINTER Temperature (C)

38 Fecal output adjustment for CETI Temp Adj Factor Temperature (C) NRC PRO

39 Impact of humidity (%) on fecal output in the CETI equation under a 96/74 F max/min temperature regime and 5 mph windspeed and 12 hours of sunlight exposure. % Decrease to Fecal Output Humidity (%)

40 Negative associative effects suppress fecal output (appetite drive and digestibility of the consumed forage. Adjustment (%) Steer kg, Forage 13% CP, 62% DOM Maize Intake (% Body Weight) Intake Adjustment Digestibility Adjustment

41 Affects of Grazing Presssure on Intake Fecal Output Adjustment Grazing Pressure (gdm/kg BW)

42 Chasing Green - Restriction of Intake Chemo-behavioral feedback causes animals to focus on limited, highly-soluble green forage which reduces intake to levels where high quality forage cannot meet the protein and energy needs of the animal DO BISON CHASE GREEN?

43 THE CHALLENGE We can nutritionally profile bison in free ranging conditions..can we adapt NUTBAL PRO to predict performance or do we need a new industry decision support system? is the cattle equation sufficient or should we develop a bison specific equation for the bison industry The membership of National Bison Association must make that decision GANLAB is willing to work with NBA but we need funding to make this a reality.