LED Lighting Programs for Enhancement of Swine Performance

Juliette Delabbio Ph.D.
Director of Research and Development
Once Inc.

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Abstract:  Light is a key environmental factor that influences and directs physiological processes in all animals. In domestic boars, research has shown that there is seasonality in sperm production related to the light in the animal’s environment. Light exposure mediates the level of melatonin secretion, which ultimately affects the quality and quantity of the boar’s reproductive products.

Past research on pig photosensitivity and boar performance under different lighting treatments has provided us with rudimentary background information on lighting programs for AI units, but the results of many of these studies are limited in their application. However, because of newly developed LED technologies, more comprehensive lighting programs are now possible for farmed animals. More specifically, LED light programs can be created for boar holding units that incorporate, modulate and synchronize the three characteristics of light (intensity, wavelength and duration).

The following article is a review of the research that supports the use of comprehensive lighting programs in the swine industry, particularly in boar-holding facilities. Read the article.

Lighting for Swine Units

Lighting for Swine Units

By: Dr. Nina Taylor & AHDB

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The behaviour of the progenitor species of the pig and the anatomy and physiology of the porcine eye suggest that the domesticated pig is best adapted for dim levels of natural light. This knowledge can therefore be used to specify lighting for domesticated pigs kept either indoors or outdoors. In general, English law is based on sound scientific evidence.

Pigs use vision to discriminate between each other and select food containers, demonstrating that vision plays a role in everyday behaviours useful in commercial situations, and that correct lighting is important on pig units.

Pigs show some seasonal variation in reproductive success, with summer reduced fertility linked mainly to high temperatures, but with the potential to be affected by day length. In wild boar, decreasing daylengths stimulate reproductive behaviour, and a similar response has been reported in commercial pigs under experimental conditions. Stimulating puberty in boars by decreasing daylengths will also hasten the onset of boar taint; however lighting is a minor factor in this, with sire line traits of much higher impact. Piglets and weanling pigs may benefit from additional hours of light in order to locate food sources, but long term 24h light has proven detrimental effects on welfare for pigs of all ages and should be avoided. Keeping pigs in 24h dark has less detrimental effects than constant light, but still provides poorer welfare than a cyclical light: dark routine.

Current legislation on lighting is based on the ability of the stockkeeper to inspect animals, rather than the ability of the pigs to conduct visually oriented behaviours. There is limited evidence in the literature on the effects of spectra (coloured lights or colour balance of lights) on pig production. When red light has been used, it is likely to be perceived as dark by pigs. Dawn and dusk periods of phased illuminances have not been researched, but could provide helpful time cues to the pigs and could reduce the dazzle or confusion of rapid light change, and competition at timed feeders.

Current knowledge on flicker sensitivity suggests that the pig will have similar critical flicker fusion to the cat, and be unable to detect the flicker of correctly functioning fluorescent lights. Natural light differs in many respects from artificial light and few controlled studies have been published comparing these two sources. High levels of natural illuminance (including UV) are likely to cause sun burn and heat stroke in the pig, which must be given relief in the form of shade or wallows. Whilst pigs need natural light or UV to produce vitamin D3, deficiency of vitamin D is not considered to be a problem, and vitamin D2 is provided in a balanced diet.

This report highlights a number of areas where research onto the effects of lighting on pigs is insufficient for accurate conclusions to be drawn and where current knowledge is inconclusive or contradictory. Due to developments in commercial pig production, information on seasonality in pigs would be beneficial; if the pig is now photorefractory, then light regimes and hours of lighting could be excessive or under used, wasting energy or providing a suboptimal environment. Whilst the spatial acuity of pigs is poorer than humans, their ability to complete visually mediated biologically relevant tasks under different illuminances needs to be established; in addition, other parameters of lighting and their effects on pigs should also be examined.

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Does your site have pigs’ sight in mind?

Does Your Site Have Pigs' Sight In Mind?

By Pork Network

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Pigs don’t exactly see eye to eye with humans; in fact, they see about one-sixth the resolution we do. Understanding how pigs see can help producers manage their indoor lighting systems to give pigs the most efficient and comfortable visual environment.

Pigs have two pigment cones in each eye, which helps them decipher color vision. Humans, on the other hand, have three types of cones in our eyes. Animals with only one pigment cone (called monochromatic vision) can only see in black and white. So, pigs are not colorblind, but they don’t have the same clarity as humans.

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Building a Modern Pig Barn

Video from  Farmer Boy Ag and Ohio Pork shows