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Determining Diet. Spring. Autumn. Micronutrients. Se Co Mo Tanzania Lick 2.3 0.3 2.9 Topsoil 1.7 23 5.1 Peru Lick 0.5 13 0.7 Topsoil 0.2 13 0.7 Mills et al J Zool 2007. Natural Salt Licks. Carnivores
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Spring Autumn
Micronutrients SeCoMo Tanzania Lick 2.3 0.3 2.9 Topsoil 1.7 23 5.1 Peru Lick 0.5 13 0.7 Topsoil 0.2 13 0.7 Mills et al J Zool 2007. Natural Salt Licks
Carnivores Dietary Challenge?
Herbivores Dietary Challenge? berries Other plant Conifer needles Beans/seeds Grass, tubers cacti
Foregut fermenters Ruminants Hindgut fermenters Cervidae Bovidae
Forbs Browse Grasses
Grass Browse (shrub) Forb Antilocapra americana Availability Diet Preference
Measuring nitrogen In food In feces Bighorn ewe mass gain Fecal Nitrogen Change in Grouse Density Nitrogen (% dry matter)
Nitrogen in urine? Urea: Creatinine Ratio When is excess urea produced? Protein in diet
Preference Protein concentration Ca oxalate Concentration Javelina Example of Dietary Trade offs–
Assessing Condition 8% protein diet 16% protein diet
Body condition – Ungulate rumps
Furcula “wishbone” fat Kidney fat Bone marrow fat
KFI = Fat/Kidney X 100 Fat deposition can begin during summer in bucks but may be delayed 2 to 3 months in does because of the extreme energy demands placed on does by lactation The most appropriate application of fat indices is interpreting area differences within the same season and year or yearly differences within the same area and season
Measuring Stress - Adrenals and Stress Hormones Fecal corticoids Free Ranging Captive Adrenal glands Terio et al. 2004