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1.
1. Two experiments were conducted to examine time of oviposition for hens exposed to continuous dim lighting, to dim lighting alternating with bright lighting in a 24 h cycle or to a mixed system using bright light, dim light and darkness. 2. Under continuous dim lighting (0.3 lux), the pattern of ovipositions was the same as that reported previously for constant darkness, more eggs being laid around midnight than around noon. 3. With alternating bright and dim phases, mean time of lay was approximately 16 h after the transition from bright to dim lighting, which was 3 h earlier than under the corresponding cycle of light and dark. This phase advance was the same whether the bright:dim ratio was 16:1 or 160:1. 4. Dim lighting (1.25 lux) preceded by a period of normal lighting (5 lux or 50 lux) and followed by 8 h darkness was treated as part of the photoperiod. 5. It is concluded that, when there is no darkness, a period of dim lighting is treated as darkness, provided the contrast between bright and dim phases is sufficient. However, when darkness, dim light and bright light are all included in a cycle, the dim light is treated as part of the photoperiod, even though there may be a contrast between the brightly lit and dimly lit phases which, in the absence of darkness, would cause the dim phase to be treated as dark.  相似文献   

2.
1. Nine pairs of laying hens were observed in cages with two switches. One switch activated a motorised environmental enrichment device (mEED) whilst the other dummy switch had no effect. Over 14 d there was no difference between the mean number of pecks on switches to activate the mEED and the dummy switches.

2. The frequency of pecks to activate the mEED was negatively correlated with time.

3. A pilot study assessed the possibility that the hens had difficulty depressing the switches. In 4 cages during a second 14 d period, the active switch operated a water pump (wpEED) to release 15 ml water into the food trough. The mean pecking rate was greater than when the switch activated the mEED.

4. The results showed that the hens were insufficiently motivated to repeatedly activate a simple mEED, but indicated that they would peck a switch frequently to receive water in the food trough.  相似文献   


3.
Spectral sensitivity of the domestic fowl (Gallus g. domesticus).   总被引:2,自引:2,他引:0  
1. The spectral sensitivity of 7 broiler fowl was determined in a behavioural test. 2. Initially the birds were trained to receive a food reward by pecking at a clear, Perspex panel behind which was a light stimulus (circular, diameter = 9 mm), originating from a tungsten-halogen lamp. Subsequently, they were trained to choose between 2 panels only 1 of which was lit; the assignation of light and dark on each panel was randomly ascribed between trials. The colour of the lit panel was determined by the wavelength of the light transmitted through one of 13 closely defined narrow bandwidth filters between 326相似文献   

4.
1. Broiler breeders were reared at an initial illuminance of 13, 21 or 44 lux and transferred at 20 weeks and a mean body weight of 2.06 kg to floor pens at 25, 55 or 71 lux, or to individual cages at various intensities between 3 and 138 lux.

2. Rate of sexual maturation was not significantly affected by the light intensity experienced during the rearing period, but was progressively accelerated by the provision of a brighter illuminance after 20 weeks, up to a ceiling of about 14 lux. There was no interaction between the pre- and post-20-week illuminance.

3. Cumulative egg numbers to 39 weeks were unaffected by illuminance in the rearing period, positively correlated with illuminance post 20 weeks up to an asymptote at about 8 lux, and highly correlated with age at sexual maturity. Peak rate of lay was both delayed and depressed at 3 lux.

4. It is concluded that the minimum light intensity required at bird-head height to achieve satisfactory photostimulation and an optimal peak rate of lay in broiler breeders is 10 lux, but that a higher illuminance would be prudent for broiler breeders kept in floor pen facilities to maximise nest-box usage.  相似文献   


5.
1. Shaver White and ISA Brown pullets were reared to 140 d in cage groups of 8 on a 10-h photoperiod of incandescent light and maintained at an illuminance of 3 or 25 lux, or transferred from 3 to 25 lux or from 25 to 3 lux at 63 or 112 d of age. 2. Plasma follicle stimulating hormone (FSH) concentration at 63 and 112 d was higher in both breeds for pullets maintained at an illuminance of 25 lux compared with 3 lux. After 2-4 d, and relative to constant-illuminance controls, plasma FSH increased significantly for ISA Brown transferred from 3 to 25 lux at 63 d and for Shaver White transferred at 112 d. Irrespective of genotype, plasma FSH for pullets given a decrease in illuminance at 63 or 112 d showed a tendency for less change than did constant-illuminance controls. 3. There was no significant difference in sexual maturity for ISA Brown maintained on 3 or 25 lux, but Shaver White pullets exposed to constant 3 lux matured later than those maintained on 25 lux. Shaver White matured later following an increase from 3 to 25 lux at 63 and 112 d, and earlier subsequent to a decrease from 25 to 3 lux at 112 d. ISA Brown pullets were not significantly affected by a change in illuminance at 63 or 112 d, though their responses were in the same direction as Shaver White. 4. Changes in plasma FSH in the 2- to 4-d period following a change in illuminance at 63 or 112 d were not significantly correlated with sexual maturity.  相似文献   

6.
The present study was designed to test the effects of sudden changes of food access and light duration on the physiological and behavioral parameters of hens. The physiological parameters investigated were heart rate (HR), body temperature (BT), and locomotor activity (LA) using a radiotelemetry system. After implantation of the telemetry transmitters, six hens were housed individually in cages under constant environmental conditions for 10 days with a photoperiod of 15 h light (04.00–19.00 hours), and food was available ad libitum at all times. After that, the same hens were subjected to a feed withdrawal trial, from 12.00 to 08.30 hours, followed by a lighting hour reduction trial by changing the time of lights‐off from 19.00 to 14.00 hours. The physiological and behavioral data were recorded for 2 days before each trial, as control data. With the feed withdrawal trial, during the light and dark periods, HR and BT were significantly lower in the hens without food access than in the control. Whereas, LA was significantly lower only during the light period in the hens without food access than in the control. Further, the time spent resting increased significantly, but the time spent feeding decreased significantly in the hens without food access than in the control. Also, the number of times the cage was pecked and pecking of the feeder occured at a significantly higher level, while the number of times beaks were wiped occured at a significantly lower level in the hens without food access than in the control. With the lighting hour reduction trial, during the light period, HR and BT were significantly higher, whereas LA was significantly lower in the ’sudden light‐off’ treated hens than in the control. In addition, during the dark period, HR, BT and LA were significantly higher in the sudden light‐off treated hens than in the control. Moreover, in the sudden light‐off treated hens, the time spent preening and feeding decreased significantly, but the time spent resting increased significantly than in the control. It is concluded that sudden changes in a management program might result in many significant differences as were found in the physiological and behavioral parameters of hens in the present study.  相似文献   

7.
1. Fifty-one flocks of laying hens in two high-density loose-housing systems were studied on 25 commercial farms in Sweden as part of a government test programme for evaluating new systems for laying hens. Six different hybrids were used in group sizes ranging from 250 to 5 000 birds. Stocking-densities varied from 10.2 to 19.1 birds per m2 floor area. No birds were beak trimmed. 2. The distribution of birds in the system, the frequency and location of aggressive pecks and feather pecks, the dust bathing activity and the birds' fear reaction to the keeper and to a novel object were measured. Direct behaviour observations were carried out twice per flock, at weeks 35 and 55. 3. The proportion of birds at the different locations was relatively constant across the 8-h observation period in the tiered system, but changed over time in the perch system, which may reflect a difference in access to resources between the systems. At night the top perches/tiers were preferred although when stocking-density increased, other sites were also used. 4. Aggression occurred mainly on the litter or in the nest areas. It did not differ between hybrids, but increased with age in the tiered system. Feather pecks occurred mainly on the litter. Brown hybrids feather pecked more than white ones, while white hybrids reacted more both to the keeper and to a novel object than did the brown hybrids. 5. It was concluded that access to nests was insufficient in both systems, as was litter space. Feed space was insufficient in the tiered system if food requirements increased. Design of the top perches, in the perch system, should be improved to allow birds to perch high up in the system without blocking access to feed etc. for others.  相似文献   

8.
1. Shaver White and ISA Brown pullets were reared to 140 d in groups of 8 in cages on a 10-h photoperiod of incandescent light and maintained at an illuminance of 3 or 25 lux, or transferred from 3 to 25 lux or from 25 to 3 lux at 63 or 112 d of age. 2. There was no significant difference in sexual maturity, measured as eggs per 100 bird.d at 139 and 140 d, for ISA Brown maintained on 3 or 25 lux, but Shaver White pullets exposed to constant 3 lux matured significantly later than those maintained on 25 lux. 3. In Shaver Whites, sexual maturity was significantly delayed by an increase from 3 to 25 lux at 63 and 112 d, and advanced by a decrease from 25 to 3 lux at 112 d. Sexual maturity of ISA Browns was not significantly affected by a change in illuminance at 63 or 112 d, though responses were in the same direction as for Shaver Whites. 4. In both breeds, total feed consumed to 112 d was higher for birds on 3 lux than 25 lux, but lower between 112 d and 140 d when birds on 25 lux underwent rapid sexual development. In both breeds, body weight at 63 d was higher for birds exposed to 3 lux than 25 lux, but body weight gain thereafter was similar for the two light intensities. 5. In both breeds, plasma luteinising hormone (LH) concentration at 63 and 112 d was lower in birds maintained on 3 lux than 25 lux. At 63 and 112 d, transfers from 25 to 3 lux depressed, whereas transfers from 3 to 25 lux at 63 d, but not at 112 d, increased plasma LH. 6. Advances or delays in sexual maturity induced by changes in illuminance were not correlated with differences in feed intake, body weight gain, or with changes in plasma LH. 7. One possible explanation for the inverse relationship between the direction of change in illuminance at 63 and 112 d in pullets exposed to a 10-h photoperiod and the age at which they became sexually mature is that changes in light intensity and/or spectral composition affect the entrainment of the circadian rhythm of photoinducibility, to effect a phase shift in the photoinducible phase and/or the responsiveness of phototransduction pathways.  相似文献   

9.
1. The perception of UVA light (320 < lambda < 400 nm) by domestic fowl may be an adaptation to naturally lit habitats and may still be functional in farmed varieties, although not utilised owing to the absence of these wavelengths in commercial house lighting. One function may be the mediation of sexually related signalling or communication. 2. In experiment 1, two groups of 41 adult broiler breeders (four cockerels, 37 hens) were kept under conventional fluorescent light, with or without fluorescent UVA supplementation amounting to 16.9% of the total spectral power output of the luminaires. Each light environment was approximately iso-illuminant as perceived by the birds. The two groups were exposed to the light environments alternately for five 2-day periods in a cross-over design. Mating behaviour, production measures and time budgets were recorded on the second day of each period. 3. A UVA-enriched environment increased the number of attempted matings (1.27 vs 0.99 matings/cockerel.h) and locomotion (5.3 vs 3.7 min/bird.hour). 4. In a second experiment, 10 hens were allowed to choose between four cockerels lit under different power levels of UVA (1.6%, 14.6%, 43.5%, 57.5% of the total spectral power output of the luminaires) in a four-armed maze. Again, each light environment was approximately iso-illuminant as perceived by the birds. Each hen was allowed to make one choice per day over four days, with the position of the cockerels and the UVA levels interchanged each day. This schedule was repeated with the same hens for two other groups of four cockerels. 5. At a distance of no less than 60 cm from the cockerel, the hens spent most time inspecting whichever cockerel was lit by 1.6% or 14.6% UVA (1.33 vs 1.37 vs 1.22 vs 1.16 log seconds/hen.choice, respectively for increasing UVA level). Similarly, when allowed to approach closer to the cockerels, the hens spent most time in the arm which contained a cockerel lit by 14.6% UVA light, (1.62 vs 1.88 vs 1.69 vs 1.51 log s/hen.choice, respectively for increasing UVA level). 6. UVA is clearly implicated in the transmission of sexual signals or communication which may have implications for the welfare and production of broiler breeders.  相似文献   

10.
1. Sex‐linked albino (s al ) and S (Silver) female chicks were hatched from heterozygous sires from a brown egg‐type line. They were raised in a windowless house and at 17 weeks of age were caged individually in 4 rooms with white fluorescent tubes: two rooms had a “low” light intensity (less than 10 lux) and two had a “high” intensity (average near 400 lux). In total, 157 females completed the experiment.

2. Body weight, sexual maturity, egg weight, the number of abnormal and cracked eggs, efficiency of food utilisation and mortality were not affected either by lighting treatment or by genotype.

3. The genotype X treatment interaction was highly significant for egg number, laying percentage and clutch length to 362 d. The S females were not affected by light intensity. Albino hens of “high” light intensity were superior to the other 3 groups, laying 12 per cent more eggs than non‐albino hens; but their egg production was moderately depressed by “dim” light relative to others.  相似文献   


11.
1. Commercial laying hens are commonly housed in noisy and dim environments, yet relatively little is known about whether these conditions, particularly in combination, have any effect on welfare or egg production.

2. The study was designed to investigate whether chronic exposure to continuous noise (60?dB(A) vs. 80?dB(A)) and/or light intensity (150?lux vs. 5?lux) during the critical period of coming into lay (16–24 weeks of age) influenced behaviour (activity, resting and feather maintenance), physiological stress (plasma corticosterone and heterophil to lymphocyte ratio) and production (number and weight of eggs laid) in laying hens.

3. Hens in the low light pens were less active and preened and dust-bathed more than those housed in 150?lux; hens in the high noise pens rested more frequently than those in quieter pens.

4. There was no evidence that chronic exposure to low light or high noise caused appreciable physiological stress but egg production was affected by these conditions. Hens kept in pens with low light or high noise laid fewer eggs per day than those kept in high light or low noise pens. These effects were additive, so that the fewest eggs were laid by hens subject to both low light and high noise.

5. These results show that low light intensity and continual high background noise have a detrimental effect on egg production in the early laying phase as well as influencing the time allocated to different behaviours. However there was no strong evidence for a physiological stress response to either of these conditions or their combination.  相似文献   


12.
Effect of foraging material and food form on feather pecking in laying hens   总被引:2,自引:0,他引:2  
1. The aim was to test whether provision of foraging material and food form influence feather pecking and feather damage in laying hens. 2. From week 19 of age, 16 groups of 11 hens (white Lohman Selected Leghorn hybrids) were kept in pens with or without access to long-cut straw as foraging material and fed on either mash or pellets. 3. Foraging behaviour was increased in hens with access to straw and time spent feeding was increased in hens fed on mash. In addition, hens fed on mash had longer feeding bouts and higher rates of pecking at the food during feeding than hens fed on pellets. 4. There were interaction effects of foraging material and food form on both feather pecking and feather damage. High rates of feather pecking and pronounced feather damage were only found in hens housed without access to straw and fed on pellets. In groups characterised by high rates of feather pecking the hens also showed more severe forms of this behaviour. 5. Differences in the time budgets of hens kept in different housing conditions suggested that birds fed on mash used the food not only for feeding but also as a substrate for foraging behaviour. 6. In order to avoid problems with feather pecking it is recommended that laying hens are provided with foraging material and fed on mash.  相似文献   

13.
1. The influence of fluorescent and incandescent artificial lighting in a 16L:8D day/night schedule on number and intensity of movements, and on total, resting and activity‐related energy expenditure was investigated.

2. Fluorescent light showed the same positive correlation between light intensity and physical activity at all activity levels as was found previously for incandescent light.

3. Light‐dependent physical activity under fluorescent light was higher than under incandescent light at illuminances of 5 lux and above, indicating the fowl's ability to perceive qualitative light differences.

4. Total and activity‐related energy expenditure were positively associated with illuminance; resting energy expenditure was not influenced.

5. Total, resting and activity‐related energy expenditure were not statistically significantly different between light sources.

6. The results are discussed in relationship to Teichmuller's concept of adequate lighting and the characteristics of the fowl's visual system.  相似文献   


14.
Six hens were trained in a trial-by-trial auditory discrimination in which trials were signalled by the lighting of two key lights. Correct responses (left-key pecks when a tone was presented and right-key pecks when it was not) produced intermittent deliveries of food. Following training at one tone frequency and intensity, testing sessions at lower intensities were carried out. Training and testing were repeated for 10 frequencies between 260 Hz and 8000 Hz. Derived measures of detection performance allowed estimates of the intensities at which no discrimination would have occurred. The threshold measures are presented and suggest that the range of most sensitive hearing was between 3000 and 5000 Hz.  相似文献   

15.
1. Energy balance of adult hens divergently selected for high (R + ) or low (R- ) residual food consumption was investigated using indirect calorimetry. Three experiments were conducted: feeding behaviour of individual hens, hens having free access to food or fasting and hens tube-fed at 70, 100 or 130% of the control intake of both lines. 2. R + hens ate significantly more than R- (+ 48%). This difference was maximum at the onset of the light (+ 120%) and not significant during the rest of the light period. Although both lines spent the same total time eating, R + hens exhibited more frequent but shorter meals than R- ones, suggesting a higher feeding activity in R + hens. 3. True metabolisable energy (TME) intake was 28% greater in R+ than in R- birds. Basal heat production did not differ significantly between genotypes. Heat increment of feeding (HI) or diet-induced thermogenesis was significantly enhanced in R + birds: + 23.9 vs 13.7 kJ/100 kJ TME intake in R- . 4. When tube-fed and placed in darkness, restricted-fed R + hens had the same HI as R- birds. When fed at 100% and 130% of control intake, R + hens demonstrated a regulatory thermogenesis, which allowed them to dissipate the excess of energy ingested compared to R- hens. 5. No significant modification was observed in plasma triglyceride, phospholipid, uric acid, glucose or insulin concentrations between lines, suggestive of the use of similar thermogenic pathways. While plasma triiodothyronine (T3) concentrations did not differ between genotypes, plasma thyroxine (T4) appeared higher in unfed R + birds and equal in fed conditions in both lines. 6. A regulatory part of HI allowed R + hens to get rid of their excessive energy intake. An increased turnover of lipids could be involved.  相似文献   

16.
1. Two short-term trials are described in which laying hens were exposed to 8 h light followed by 8 one-min pulses of light at hourly intervals followed by 8 h darkness (8L:8i:8D). The effect of varying the intensity of illumination during the one-min pulses and the effect of placing the intermittent lighting before the 8 h photoperiod (8i:8L:8D), were studied. 2. Normal egg production was maintained by the 8L:8i:8D system when the light pulses were at 20 lux, but not at 5 lux. This suggests a minimum threshold for illumination with short light pulses higher than that needed for continuous lighting. 3. Time of lay under 8L:8i:8D was the same as with 8L:16D in relation to the beginning and ending of the 8 h main photoperiod, but with 8i:8L:8D mean time of lay was 2 to 3 h earlier. Thus the hourly pulses caused a phase advance when placed before the normal photoperiod but did not cause a phase delay when placed after the normal photoperiod.  相似文献   

17.
1. Two lines of commercial hybrid layers (Tetra and ISA Brown) were reared from hatch to 30 weeks of age in groups of 8. The objectives of the experiment were to evaluate the significance of the different selection practices involved in the development of the lines and to assess the potential association between selected behavioural states and the potential for feather damage and cannibalism. 2. Behavioural tests related to fear (tonic immobility, novel object, open field), sociality (runway, proximity in the home pen) and pecking (feather bunch and focal observations of inter-bird and environmental pecking) were conducted at 0 to 2, 5 to 7, 12 to 14, 19 to 21 and 29 to 31 weeks of age. Scan sampling of general behaviour was also conducted at these ages. 3. Underlying sociality was greater in Tetras than in ISA Brown hens. 4. There were no apparent overall strain differences in fearfulness although ISA Brown hens showed significantly longer tonic immobility fear reactions than Tetras at 31 weeks of age. 5. ISA Brown hens gave and received more gentle pecks than Tetra hens whereas preening was commoner among Tetras. There were no strain differences in the number of pecks at litter or food. 6. As birds aged they showed less avoidance of novel objects and Tetras, though not ISA Browns, showed progressively shorter tonic immobility responses. Birds of both strains spent less time resting, more foraging (pecking and scratching) and pecked more at the feather bunch at older ages. 7. Measures taken in the TI, open field, runway (social affiliation) and feather bunch tests were stable over time whereas focal observations of pecking at hens and the environment were not. 8. Factor Analysis showed that 3 factors defined by the novel object test, environmental pecking and pecking ata feather bunch explained most of the variation in the correlation matrix between summary measures for the 8 behavioural traits.  相似文献   

18.
This study consisted of two experiments: the first was conducted with Large White turkey males during the spring and summer (experiment 1) and the second during the autumn and winter (experiment 2). When 56 d of age, the birds were assigned to light-controlled pens and exposed to continuous illumination. Light sources used were incandescent, daylight fluorescent, warm fluorescent or high pressure sodium vapour lamps at light intensities of 10.8 or 86.1 lux. Results obtained showed that the light sources used had no significant effects on growth performance, efficiency of food utilization, feather scores or live bird quality of Large White turkeys. Social encounters were higher in birds reared under fluorescent and sodium vapour lights and mortality was higher in birds under fluorescent lights in experiment 1. Behaviour, feather scores, live bird grade and mortality were unaffected by light source treatments in experiment 2. Light intensity had no significant effect on growth, efficiency of food utilization, feather scores or bird market quality. Social encounters and mortality were higher in males exposed to 86.1 lux of light intensity.  相似文献   

19.
Routine removal of the tip of the beak of chickens within the poultry industry leads to changes in pecking behavior, which have previously been interpreted as being indicative of pain. By analyzing the force of pecks, with and without the topical application of an analgesic to the beak, we investigated if changes in pecking behavior were due to a loss of sensitivity in the beak or were pain related. Pecking behavior was compared between intact-beak and beak-trimmed chicks with or without topical application of lignocaine during a pain-free period (within 24 h of beak trimming) or after this period (d 2 to 9 of age). After pecking behavior tests, chicks were trained to use a magnetic stimulus to locate hidden food in 1 corner of a square arena. In unrewarded magnetic tests, the location of the chick relative to the magnetic stimulus was determined by automatic image recognition. Beak-trimmed chicks pecked harder than intact-beak chicks within 24 h of beak trimming (P = 0.04), possibly as a means of compensating for the loss of sensory feedback in beak-trimmed chicks. At 2 to 9 d of age, beak-trimmed chicks took longer to peck the pecking stimulus (P < 0.001) and showed fewer pecks in total (P < 0.001), suggesting a reduced pecking motivation. The force of pecks, however, did not differ among treatments at 2 to 9 d of age, suggesting that beak-trimmed chicks were not experiencing pain from the beak. In the magnetic tests, hungry intact-beak chicks stayed nearer to the magnetic stimulus (P = 0.005) and spent proportionally more time within 125 mm of the magnetic stimulus (P = 0.02) that had previously been associated with food than beak-trimmed chicks, which indicated that intact-beak birds were better able to detect the magnetic stimulus than beak-trimmed birds. We concluded that minor beak trimming at a young age did not result in pain in young domestic chicks, but instead led to impaired function of the magnetoreceptors and mechanoreceptors of the beak.  相似文献   

20.
1. Two experiments were conducted to provide further evidence about rate of lay under the Cornell lighting system (2L:4D:8L:10D). Each used 1728 hens of each of 2 brown-egg stocks in 12 light-proof rooms. 2. In the first the Cornell system was compared at 2 light intensities (average values 2 and 10 lux) with a conventional step up lighting programme. In the second, Cornell lighting was introduced at 18, 21 or 24 weeks of age and compared with a step up programme. 3. Total egg output was essentially the same from the Cornell lighting system, using 10 h light/d, as from the step up programme using 16 h/d. When the Cornell system was applied abruptly at 18 weeks to pullets which had been reared on short days (8L:16D) sexual maturity was advanced, resulting in an increase in mean rate of lay to 72 weeks of age and a reduction in mean egg size. Application of the Cornell system from 21 or 24 weeks gave the same egg numbers and the same egg size as the step up programme. 4. Food intake was about 2% lower with the Cornell treatment in both experiments. Although this difference was not quite significant in either, it probably reflects a real effect of the reduced hours of light. It represents a greater potential cost saving than the reduced electricity consumption. 5. Birds in rooms with an average light intensity of 2 lux laid slightly fewer eggs but their eggs were 0.5 g heavier than those laid in rooms maintained at 10 lux. There were no interactions between light intensity and light pattern or between stocks and light pattern.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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