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1. The objective of the present study was to examine the effect of lighting programs and light colour on ocular health variables as welfare indicators in Ross 308 broilers.2. A total of 384, male, one-d-old broiler chickens (Ross 308) were placed in a completely randomised design with a 2 × 2 factorial arrangement of lighting program (continuous or intermittent) and light colour (white and green LED light). Ross 308 broilers under restricted lighting had 18 h of light (18 L:6D), while those under intermittent lighting had cycles of 17 L:3D:1 L:3D throughout the experimental period, which lasted 42 d.3. At the end of the experiment, all eyes of birds (n = 96 birds) underwent a complete ophthalmic examination, which included the Schirmer tear test I, intraocular pressure and eye dimensions. In addition, 32 broilers (eight birds per trial groups) aged 42 d underwent ophthalmic examination to include assessment of ocular ultrasound biometry.4. Light colour had a significant influence on the mean intraocular pressure (p < 0.001). The Ross 308 broilers kept with intermittent lighting had lower eye weights (2.29 g; p < 0.05), palpebral fissure length (14.39 mm; p < 0.01), eye dorsoventral diameter (17.46 mm; p < 0.05), anteroposterior size (13.70 mm; p < 0.01) and corneal dorsoventral diameter (7.81 mm; p < 0.05) compared to those reared under restricted lighting.5. In conclusion, these values for Ross 308 broilers may be applied in poultry ophthalmology to detect early eye disease symptoms and to help the diagnosis of tear disorders that could cause economic losses and welfare issues. Intermittent lighting and green LED light may help reduce eye health problems thus contributing to improved welfare in broilers. [ABSTRACT FROM AUTHOR]

Lighting from red and blue light-emitting diodes (LEDs) is common for crop production in controlled environments. Continuous application of red or blue light at night has been shown to suppress sporulation by Peronospora belbahrii, the causal organism of basil downy mildew (DM), but the suppressing effects of intermittent applications of red and blue LEDs have not been thoroughly researched. This study examined the effects of red (λmax = 670 nm) and blue (λmax = 458 nm) LED top lighting, at two photosynthetic photon flux densities (PPFD = ≈12 and ≈60 µmol·m−2·s−1), using continuous (10-hour) nighttime and two intermittent nighttime exposures, to suppress basil DM sporulation. The two intermittent treatments consisted of one 4-hour exposure and three 1.3-hour exposures spaced 3 hours apart. Continuous nighttime treatments with blue or red LED top lighting at ≈60 µmol·m−2·s−1 were able to suppress basil DM sporulation by more than 99%. At a given nighttime dose of light that did not completely suppress sporulation, continuous lighting was more effective than intermittent lighting, and for these partially suppressing doses, red LEDs were not significantly different from blue LEDs for suppressing sporulation. The present study showed that horticultural lighting systems using red and blue LEDs to grow crops during the day can also be used at night to suppress basil DM sporulation by up to 100%.

Lighting from red and blue light-emitting diodes (LEDs) is common for crop production in controlled environments. Continuous application of red or blue light at night has been shown to suppress sporulation by Peronospora belbahrii, the causal organism of basil downy mildew (DM), but the suppressing effects of intermittent applications of red and blue LEDs have not been thoroughly researched. This study examined the effects of red (lmax = 670 nm) and blue (lmax = 458 nm) LED top lighting, at two photosynthetic photon flux densities (PPFD = '12 and '60 mmol·mL2·sL1), using continuous (10-hour) nighttime and two intermittent nighttime exposures, to suppress basil DM sporulation. The two intermittent treatments consisted of one 4-hour exposure and three 1.3-hour exposures spaced 3 hours apart. Continuous nighttime treatments with blue or red LED top lighting at '60 mmol·mL2·sL1 were able to suppress basil DM sporulation by more than 99%. At a given nighttime dose of light that did not completely suppress sporulation, continuous lighting was more effective than intermittent lighting, and for these partially suppressing doses, red LEDs were not significantly different from blue LEDs for suppressing sporulation. The present study showed that horticultural lighting systems using red and blue LEDs to grow crops during the day can also be used at night to suppress basil DM sporulation by up to 100%. [ABSTRACT FROM AUTHOR]

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

Necrotic enteritis, either in its clinical or sub-clinical form is known to cause massive economic losses in the broiler chicken industry. Currently, the use of in-feed antibiotics as growth promoters is discouraged. Therefore, mechanisms to control NE through diet include reduction of digesta viscosity, promotion of lower pH in the gastrointestinal tract (GIT) through acidification of feed, production of short-chain fatty acids and overall stimulation of beneficial bacteria growth. Intermittent lighting programs increase feed retention in the crop and reduce pH in the foregut compartments in comparison with standard commercial lighting programs and therefore may be a valuable, yet underexploited, barrier to prevent the invasion of the GIT by pathogens. In this experiment, a 2 × 2 factorial arrangement of treatments was employed in a randomized design to investigate whether intermittent lighting would increase broiler resilience to sub-clinical necrotic enteritis. A total of 390 Cobb 500 same-hatch, mixed sex, day-old chicks were assigned to 30 floor pens to test the effect of 2 factors, namely, lighting schedule (continuous, 18L:6D vs. intermittent, 1L:3D:1L:3D:1L:3D:1L:3D:2L:6D) and a subclinical necrotic enteritis challenge (challenge vs. no challenge). Challenged birds had lower feed intake and weight gain and poorer feed conversion ratio (FCR; P < 0.005). Intermittent lighting reduced feed intake (P < 0.05) without compromising final body weight gain. During the peak phase of Clostridium perfringens Type A infection, the negative impact of the disease challenge on feed efficiency was lower for animals under intermittent lighting than for those under a 18L:6D schedule (2-way interaction, P < 0.005). Thus, in flocks that are raised under antibiotic-free production systems, intermittent lighting programs applied at least during the critical period for necrotic enteritis risks, i.e., d 18-24, may be a practical, non-medicated way to increase resilience of broilers to this disease. [ABSTRACT FROM AUTHOR]

Foi avaliado o efeito de programas de iluminação sobre o desempenho zootécnico de poedeiras leves ao final de produção, em experimento realizado no Departamento de Zootecnia da Universidade Federal de Lavras - UFLA. Foram testados um programa de iluminação intermitente e outro com apenas iluminação natural, em dias de luminosidade crescente, em comparação com um programa contínuo com a utilização de 288 poedeiras leves da linhagem Leghorn branca. As aves foram alojadas em galpão dividido em 3 ambientes, por lona de plástico preta, de forma que a iluminação de um não interferisse na dos outros. Cada ambiente experimental apresentou 32 gaiolas nas quais foram alojadas 96 galinhas. Foi realizado um período pré-experimental de 28 dias. O período experimental teve duração de 112 dias, em que avaliou-se o consumo de ração, a produção de ovos, o peso e a massa dos ovos e a conversão alimentar por massa de ovos. O delineamento utilizado foi o inteiramente ao acaso, com restrição nos tratamentos, e oito repetições. As aves submetidas ao programa de iluminação intermitente e iluminação natural consumiram (P0,05) nos programas de iluminação testados. A produção e a massa de ovos foi maior (PThis experiment was conducted with objective to evaluate the effect of lighting programs for light at the Department of Animal Science of the Federal University of Lavras . An intermittent lighting program and another with only natural lighting on days of increasing lighting as compared with a continuous program by utilizing 288 light layers were tested. The hens were keept in a house divided into three environments in such a way the lighting of one did not interfere with that of the other one. The experimental period lasted 112 days , divided into four periods of 28 days. The design utilized was the completely randomized with restriction in the treatments and eight replicates. The means of the treatments were compared with the SNK test (5%). The hens of the continuous lighting program presented greater feed intake (P

Broilers are currently reared under nearly continuous lighting (CL) schedules. However, the suitability of such lighting regimens may be questioned in terms of performance and welfare. This paper reviews the literature concerning the effects of intermittent lighting (IL) schedules on these issues. Final body weights at market age of broilers reared under IL schedules are equal to, or even higher than, those of broilers reared under CL schedules. However, endogenous (genotype and sex) and exogenous (dietary composition, feeder space, etc.) factors may interact with the lighting schedule. In contrast, feed conversion is consistently improved with IL, partly as a consequence of a more concave growth curve (initial growth depression followed by compensatory growth). Inconsistencies in the literature concerning the effect of IL on (abdominal) fat content and dressing yield are caused by interactions with other factors. However, it is clearly demonstrated that IL reduces leg abnormalities, in particular the incidence of twisted legs. Additional welfare benefits of IL are found in reduced physiological stress and improved eye condition. An increase in the amount of catching damage has been observed with IL, but this may be avoided by modifying light management before commencement of the catching operation. The importance of light is not restricted to the lighting schedule; aspects of the light quality are also important. Although the data related to light intensity are conflicting, it is generally recommended that an intensity of 51ux should be provided. Whilst fluorescent light does not affect broiler performance adversely, its lower use of electricity compared with incandescent lighting does reduce input costs. More research is needed to evaluate the impact of these qualitative aspects of lighting on poultry welfare. [ABSTRACT FROM PUBLISHER]

Pairs of electrocutor-grid ultraviolet light traps were assigned to three treatments to evaluate the effects of illumination events, e.g. light traps turned on, on house fly, Musca domestica L. attraction as indicated by numbers of flies captured by the traps. Both traps in treatment 1 were illuminated constantly (no illumination event). Both traps in treatment 2 were turned on, illuminated for 1 h, then turned off for 1 h, then repeated (1 illumination event every 2 h). Traps in treatment 3 were operated singularly. One trap was turned on for 1 h, then turned off. As it turned off, the other trap turned on for 1 h, then turned off, then repeated (1 illumination event every hour). The mean number of flies attracted per trap pair was significantly greater in treatment 1 than in treatments 2 or 3. However, in treatment 3, with one trap illuminated at a time and hourly illumination events, the mean fly catch was just 27% less, numerically, than the mean number of flies attracted to treatment 1 with both traps illuminated constantly. The effects of intermittent lighting and its potential use are discussed. [ABSTRACT FROM AUTHOR]

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.