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Puberty Onset Influencing Factors - Anatomy & Physiology (view source)
Revision as of 07:37, 9 September 2008
, 07:37, 9 September 2008→Sheep
* Autumn born lambs do not reach puberty until 10-12 moths of age.
* Autumn born lambs do not reach puberty until 10-12 moths of age.
* This is because, seasonal cues (long days of spring/summer) delay reproductive cyclicity.
* This is because, seasonal cues (long days of spring/summer) delay reproductive cyclicity.
* Thus, oestrus in both spring and autumn born lambs is synchronised.
* Thus, [[Reproductive_Behaviour_-_Oestrus_Behaviour_-_Anatomy_%26_Physiology|oestrus]] in both spring and autumn born lambs is synchronised.
* This maximizes the chance that all ewes become pregnant in the fall and give birth in the spring when nutritional and environmental conditions are favourable.
* This maximizes the chance that all ewes become pregnant in the fall and give birth in the spring when nutritional and environmental conditions are favourable.
* An adequate degree of nutrition ('fatness') is required before photoperiod can exert an effect.
* An adequate degree of nutrition ('fatness') is required before photoperiod can exert an effect.