Livestock sector has been considered back bone of Indian farmers. India has cattle and buffalo population of 190.90 and 108.7 million respectively which are major contributors of milk production in the country (19th livestock census, 2012) but, the productivity of our animals are not at par with that of exotic animals. However, it can be improved by better management.
New concepts of dairy farming managerial practices are coming into force these days with their varied benefits. One of those important managerial practices is photoperiod management.
Dairy cow subjected to short day light period during dry period may lead to increase in milk production by 3.2 kg/ day in subsequent lactation period when long day light period is followed.
It has been found that long day light periods (16 to 18 hours of light) are generally recommended for management practice to improve overall milk yield and lactation efficiency in lactating cattle. Differently, the converse effect of shorter day light period (8 hours of light) has been found effective during dry period of dairy cattle. Day light period during dry period management affects milk yield in cows in forthcoming lactation stage. Short days light during dry period is associated with increased milk yield thereafter.
Manipulation of photoperiod for either longer day light or short days light period does not leads to increase in feed intake but, due to effect of photoperiod physiological changes take place resulting in better milk yield.
Change in photoperiod is an important management practice to improve the milk performance of cows but, physiological parameters like stage of lactation, level of milk production, parity of cows, etc. should be taken into consideration while altering the duration of light period for both lactating and dry cows.
Light intensity of 150 to 200 lux is necessary to produce significant response in both long and short day light periods. In long day light period there should be consistent 16 to 18 hours of light using white lumen bulbs or lamps consistently for 6 to 8 hours of darkness by keeping animals into dark room generally during night. In short day light period maximum 8 hours of consistent light period should be made available to the dairy cow with continuous 16 hours of dark period.
On an average, height of 12 to 20 feet above the ground level, whichever convenient, would be sufficient to light up the lighting source. A bulb providing blue- white light are found to be most suitable for this process. These types of light source examples are tube rods, CFL’s (Compact fluorescent), etc. of 60- 150 watts.
Use of low intensity red lighting of 7 to 15 W incandescent bulbs can be used for checking animals during lactation or dry period without affecting response to the light sensation. This type of light does not create sense of sight.
Photoperiod management is quite easy way to improve milk production and performance; it could be adopted even in an ordinary dairy farm which is traditional as well as modern type farms. It is quite effective and convenient method, it does not require a high investment or any sophisticated implement installment. Not much cost would be needed for making electrical connections for bulbs to glow. Moreover, it does not change the milk composition of cow’s milk. After the calving, lactating cow should be gradually shifted for long day light period for optimum results.