Animal Science Department


Date of this Version

March 1985


Published in JOURNAL OF ANIMAL SCIENCE, Vol. 61, No. 3, 1985. Copyright American Society of Animal Science. Used by permission.


Three experiments of 5 wk duration were conducted to evaluate the effect of reduced nocturnal temperatures (RNT) on weaned pig performance. Treatments were 1) a control regimen (CR) of 30 C constant air temperature lowered 2 C/wk and 2) a regimen where the temperature from 1900 to 0700 h was lowered to 25 C for three nights followed by 20 C for four nights during the first week and then lowered 1 C/wk thereafter (RNT). Weaned pigs averaging 23 ± 2 d of age at the start of the experiments gained faster (P<.01) in the RNT treatment vs the CR treatment in Exp. 1, 2 and 3, respectively (.32 vs .28; .39 vs .37; .35 vs .34 kg/d). The improvement in gain was accompanied by an increase (P<.005) in feed intake for the same period (.48 vs .44; .61 vs .55;.58 vs .54 kg/d). There was no difference in feed conversion. Weaned pigs that were 1.9 to 2.3 kg lighter initially gained slower (P<.0005) compared with their heavier contemporaries (.27 vs .33; .33 vs .43 and .31 vs .33 kg/d) in Exp. 1, 2 and 3, respectively, This reduced gain was accompanied by a reduced (P<.0005) feed intake (.40 vs .51; .50 vs .66; .50 vs .62 kg/d). There was no interaction of initial weight and temperature regimen.