caa a22 4500 386321213 CHVBK 20180307111627.0 cr unu---uuuuu 161130e198804 xx s 000 0 eng 10.1017/S0003356100042380 doi S0003356100042380 pii (NATIONALLICENCE)cambridge-10.1017/S0003356100042380 A note on the effects of previous photoperiod exposure and gradual transitions of light intensity at dawn and dusk on growth in Holstein heifers [Elektronische Daten] Long-day photoperiods of 16 h light (L) and 8 h dark (D) stimulate a proportional increase in live-weight (LW) gain of peripubertal Holstein heifers of 0·08 to 0·17 compared with heifers exposed to short days of less than 12 h L per day (Peters, Chapin, Leining and Tucker, 1978; Peters, Chapin, Emery and Tucker, 1980; Petitclerc, Chapin, Emery and Tucker, 1983; Zinn, Chapin and Tucker, 1986). One factor that could account for some of this variation in the magnitude of the growth response to long days is that the previous photoperiod exposure may influence the response to a subsequent different photoperiod (Moore-Ede, Sulzman and Fuller, 1982). For example, exposure to 13L: 11D induced pulsatile activity of serum luteinizing hormone (LH) in ewes previously exposed to 16L: 8D, but reduced serum LH to undetectable levels in sheep previously exposed to 8L: 16D (Robinson and Karsch, 1987). Thus, sheep exposed to identical photoperiods exhibited different responses depending on previous photoperiod exposure. Copyright © British Society of Animal Science 1988 Zinn S. A. Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA Chapin L. T. Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA Tucker H. A. Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA Animal Production Cambridge University Press 46/2(1988-04), 300-303 0003-3561 46:2<300 1988 46 ASC https://doi.org/10.1017/S0003356100042380 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0003356100042380 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zinn S. A. Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA NATIONALLICENCE 700 1- Chapin L. T. Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA NATIONALLICENCE 700 1- Tucker H. A. Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA NATIONALLICENCE 773 0- Animal Production Cambridge University Press 46/2(1988-04), 300-303 0003-3561 46:2<300 1988 46 ASC CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge