Nocturnal Light Pulses Lower Carbon Dioxide Production Rate without Affecting Feed Intake in Geese

Abstract

This study was conducted to investigate the effect of nocturnal light pulses (NLPs) on the feed intake and metabolic rate in geese. Fourteen adult Chinese geese were penned individually, and randomly assigned to either the C (control) or NLP group. The C group was exposed to a 12L:12D photoperiod (12 h light and 12 h darkness per day), whereas the NLP group was exposed to a 12L:12D photoperiod inserted by 15-min lighting at 2-h intervals in the scotophase. The weight of the feed was automatically recorded at 1-min intervals for 1 wk. The fasting carbon dioxide production rate (CO2 PR) was recorded at 1-min intervals for 1 d. The results revealed that neither the daily feed intake nor the feed intakes during both the daytime and nighttime were affected by photoperiodic regimen, and the feed intake during the daytime did not differ from that during the nighttime. The photoperiodic treatment did not affect the time distribution of feed intake. However, NLPs lowered (p<0.05) the mean and minimal CO2 PR during both the daytime and nighttime. Both the mean and minimal CO2 PR during the daytime were significantly higher (p<0.05) than those during the nighttime. We concluded that NLPs lowered metabolic rate of the geese, but did not affect the feed intake; both the mean and minimal CO2 PR were higher during the daytime than during the nighttime.

Nocturnal One-Hour Lighting Stimulates Gonadal Development and Lowers Fat Deposition in Male Mule Ducks

“…Silky starlings exposed to short days had higher feed intakes than those exposed to long days [23]. The feed intake in mature Chinese geese subjected to nocturnal 15-min lighting periods at 2-h intervals was similar to that in control geese subjected to 12 h of light and dark per day (12L/12D) [24]. In broilers, feed intake increased with the photoperiod during the first 21 days but was not affected later by photoperiods longer than 6 h [25].…”