@conference {89230,
	title = {A Longitudinal study of production and survivability of carry-over cows in a commercial dairy herd},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {73},
	year = {2013},
	month = {Jan},
	pages = {96-99},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {<p>In earlier work, we showed that two cohorts of carry-over cows produced 10\% more milksolids (MS) in the first lactation (2008/09) subsequent to the carry-over (non-lactating) season. Here we present further production data for this cohort through to the fourth post-carry-over lactation, together with production data for two further cohorts through to their second and third post-carry-over lactations respectively, and compare this to production from non-carry-over (annual calving) cows of similar breed and breeding worth (BW) in the same herd. Carry-over cow cohorts produced more MSthrough to and including the third post-carry-over lactation relative to non-carry-over cows. We term this additional production the {\textquoteleft}holiday effect{\textquoteright}. First year MS holiday effects were 57 kg (13\%) and 106 kg (23\%); second year holiday effects were 36 kg (8\%), 48 kg (10\%) and 31 kg (6\%); and third year effects were 48 kg (10\%) and 41 kg (8\%). Aggregate survivability through to the fourth post-carry-over lactations of 83\%, 82\% and 71\% respectively were broadly consistent with national survivability statistics. It is concluded that the bio-economics of carry-over cows are worthy of consideration, particularly for young cows of high BW and PW status which have previously given birth at least once.</p>
},
	issn = {1176-5283},
	author = {Pangborn MC and Woodford KB}
}
