The objective of this study was to investigate the effect of cold stress (CS) on growth performance and tibia attributes in broiler chickens with thiram-induced dyschondroplasia (TD). Four hundred 10-d-old male broilers were randomly allocated into four groups including, NT0: normal temperature (NT) without thiram; NT50: NT+thiram; CS0: CS without thiram; and CS50: CS+thiram in a completely randomized. The birds in CS groups were placed at a constant temperature of 15±1 °C during 11-20 d. Thiram (50 mg/kg) was added to the diet during 11-14 d to induce TD. Results showed that main effects of CS and thiram significantly decreased body weight (BW) and daily weight gain (WG) during 11-42 d (p<0.05). Feed intake (FI) in the thiram50 group was significantly lower than the group thiram0 during 25-42 d (p<0.05). Feed conversion ratio (FCR) in CS birds was significantly more than NT group during 25-42 d (p < .05). On 16 d, tibia width (TW) and TW to tibia length (TL) ratio were significantly higher in CS chicks compared to the NT group. TW was significantly higher in thiram50 group than thiram0 group (p<0.05). On 19 d, TL in CS chicks was significantly shorter than NT (p<0.05). On 23 d, growth plate width (GPW) in thiram50 group was significantly higher than thiram0 birds. In general, thiram increased tibial GPW and CS decreased TD severity as well as decreased growth performance in broilers.

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