Introduction
	Measurement of animal intake
	Forage effects on intake

Introduction (see text pg 85-87)

	Why? – animal intake is the key determinant of production
	Animal intake can be explicitly controlled by the pasture allowance (handout pg 252)
	Example A field has a mass of 4000 kgDM/ha If it is grazed for 2 days to a residual mass of 1000 kgDM/ha (75% utilization) by 100 cows, the animal intake will be: (4000-1000)/100/2 = 15 kgDM/cow/day

Measurement of animal intake

  Forage Effects on Animal Intake

	Pasture mass (handout fig 10.2). Grazing typically removes 33-50% of the pasture height. More height = more intake
	Maximum intake typically occurs at a pasture mass of 2200-3600 kgDM/ha
	Maximum intake for sheep is at a much lower height (6-12 cm) (handout pg 278) than for cattle (15-20 cm) (handout pg 266)
	Pasture quality (protein has little effect on intake, digestibility/fiber/NDF reduce intake) (text fig 6.1)
	Particle size (rate of passage) (text pg 93)
	Sward structure – the density of forage (kg/m³) will influence intake
	Leaf:stem ratio – stem reduces intake
	High moisture reduces intake

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  Forage Species Effects on Animal Intake

	Species effects – related to physical and chemical characteristics
	Legumes have higher intake than forages – because they have high density, high digestibility, less fiber, small particle size
	Ryegrass has greater intake than tall fescue

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  Palatability

	Palatability – the preference animals have for a forage when they are offered a choice (text pg 87)
	The effect of palatability on intake when animals have no choice is variable – depending on what was the basis of the differentiation– but usually disappears

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