PROBLEM TO BE SOLVED: To provide a breeding method in which a quantity of melatonin secreted in the body of livestock is increased, and thereby the immunity of the livestock is increased and the circadian rhythm of the livestock is less disturbed.SOLUTION: A livestock breeding method concerning one embodiment of the present invention has a first circadian cycle containing a period of applying light containing a wavelength less than 500 nm to livestock and a dark period of not applying the light to the livestock, and a second circadian cycle containing a period of applying the light containing the wavelength in a range of 570 nm-610 nm in the peak wavelength to the livestock and not applying the light of the wavelength less than 500 nm. After the first circadian cycle of the above, the second circadian cycle is performed.SELECTED DRAWING: Figure 1【課題】家畜の体内において分泌されるメラトニンの量を高めることで家畜の免疫力を高め、また、家畜のサーカディアンリズムを乱すことの少ない飼育方法を提供することを目的とする。【解決手段】本発明の一態様に係る家畜の飼育方法は、家畜に対して５００ｎｍ未満の波長を含む光を照射する期間と、家畜に対して光を照射しない暗期間と、を含む第１の概日サイクルと、家畜に対してピーク波長が５７０ｎｍ～６１０ｎｍの範囲内の波長を含む光を照射する期間を含み、かつ、５００ｎｍ未満の波長の光を照射しない第２の概日サイクルと、を有し、前記第１の概日サイクルの後に、前記第２の概日サイクルを行う。【選択図】図１
