Effect Of Cage Size Research Articles

Effect of environmental stress and immobilization on stress physiological variables in farmed mink

The effect of cage size and nest box environment on plasma cortisol, number of eosinophil leucocytes, and on frequency of leucocyte groups was measured on 132 farmed mink. The experiment included three cage sizes (0.10 m 2, 0.27 m 2, and 1.1 m 2) and cages with and without nest boxes. Furthermore, the effect of daily immobilization a mink trap for 5 or 30 min. over periods of 10 days was demonstrated. The effect of daily immobilization for 5 min. was an unchanged cortisol response to immobilization from day 1 to day 10, no effect on eosinophil leucocyte level, and a decrease of H/L-ratio from day 1 to day 10. After 30 min. daily immobilization the cortisol response decreased from day 1 to day 10, the eosinophil leucocyte level decreased, and the H/L-ratio increased from day 1 to day 10. Mink females in cages without nest boxes had a higher plasma cortisol level, a lower level of eosinophil leucogytes, and a higher H/L-ratio than mink in cages with nest boxes. No effect of cage sizes was seen on the physiological variables used. A pronounced seasonal variation has been shown in the physiological variables used. The results made it possible to conclude that the duration of individual immobility sessions is of consequence to the physiological effect of immobilization. The physiological stress level increased when farmed mink were deprived of the use of nest boxes. The effect of keeping mink in cages without nest boxes was similar to daily immobilization for 30 min. with regard to both the level of eosinophil leucocytes, the relative distribution of leucocyte types, and the H/L-ratio.

Tilapia Production in Cages: Effects of Cage Size and Number of Noncaged Fish

Abstract Growth of male Nile tilapias (Tilapia nilotica) in cages of three submerged volumes (0.64, 0.83, or 1.25 m3) were compared in four 0.12-hectare ponds stocked with noncaged Nile tilapias at rates of either 50,000 swim-up fry or 3,000 fingerlings/hectare. All cages were stocked at a rate of 250 fish/m3, and only caged fish were fed. Rate of weight gain (g/fish per day) of caged fish over 20 weeks was greater in ponds with the lower number of noncaged fish. Among the range of cage sizes tested, water exchange did not appear to be different. Rate of weight gain of caged fish tended to increase with increasing cage size, apparently as a result of decreasing feed loss.

Estrous Cycle and Related Aspects of Reproduction in Captive Asian Chipmunks, Tamias sibiricus

Reproductive patterns of free-living Asian chipmunks, Tamias sibiricus, have been described by Geinitz (1980), Ognev (1940), and Shubin (1964), who reported on breeding seasons, litter sizes, approximate length of gestation, and emergence ages of young. Ognev (1940) also mentioned mating calls by females. Some aspects of reproduction, however, are observed more easily in captivity than in the wild. Because female Asian chipmunks vocalize when in estrus, even in captivity (Blake and Gillett, 1984; Imaizumi, 1972), the estrous cycle is detected easily in captive females. Herein, we report information on estrous calling behavior, length of the estrous cycle, mating behavior, breeding seasons, gestation period, number of litters per year, litter size, and sex ratio for captive Asian chipmunks. Asian chipmunks were imported into Great Britain until 1971 and since have been maintained in captivity. In the course of a study of conditions for breeding captive Asian chipmunks (Blake and Gillett, 1984), we surveyed private breeders in Britain and accumulated data on reproduction. The original stock for the chipmunk colonies was reported by importers to have come from Japan and Korea, but we do not know the exact locations. Subsequent interbreeding among the descendants makes it impossible to refer the chipmunks to subspecies. Some data on time of breeding, and number and sex of young came from our own colonies. We studied our colonies for 9 years (KEG) and 3 years (BHB), respectively, for a total of 29 female-years, where a female-year is 1 year in the life of one female. Our colonies were kept indoors in large cages, 0.6 by 0.6 by 1.8 m (BHB), or 0.9 by 0.5 by 0.4 m with daily exercise in large indoor and outdoor areas as large as 7 by 5.9 by 2.8 m (KEG). BHB's colony was in London, and KEG's colony was in Somerset Co., England for 6 years and in Amman, Jordan for 3 years. BHB's colony was observed for about 0.5 h daily, 5 days a week, and KEG's colony was observed for 4 h or more, 6 or 7 days a week. Additional data came from private breeders who recorded breeding dates, birth dates, and number and sex of young. These data and our own allowed us to determine breeding and gestation times, and number, size, and sex ratio of litters. Most of this information came from five breeders who kept detailed records for periods ranging from 5 to 17 years (115 female-years). Their colonies were in outdoor cages ranging in size from small (0.6 by 0.5 by 0.5 m) to large (2.4 by 1.9 by 2.4 m), and, in one colony, also in small indoor cages (1.0 by 0.4 by 0.6 m). Breeders observed their chipmunks daily for periods from 2 min to 3 h, with an average of about 15 min/day (and longer when mating and parturition were anticipated). Eight other breeders, with chipmunks kept under similar conditions, provided numbers and sex of young at weaning. More information on breeders and their colonies is given in Blake and Gillett (1984). Litters were born in nest boxes and remained there until they emerged at weaning. Because most breeders did not disturb young in nest boxes, litter size and sex of young were determined at weaning, rather than at birth. However, few nestlings died (except when entire litters died); one breeder who inspected infants the day after birth found that only 3.3% (four of 123 young, n = 31 litters) died between birth and weaning. In comparing litter size under different conditions, pairwise tests were used to eliminate effects of cage size, which was correlated with litter size (Blake and Gillett, 1984); comparisons were made between litters within the same female-year for first and second litters of the year, or between litters born in different years to the same female for maternal age and experience. Information on estrous calling behavior came from our colonies and two breeders' colonies. We determined lengths of estrous cycles for three females in KEG's colony from the day calling began in one cycle to the day it began in the next. These females were unmated, and dates were recorded for periods ranging from 1 to 4 years for a total of 7 female-years. We also recorded beginning and ending of the calling season for a fourth unmated female, giving a total of 8 female-years for length of calling season.

Cage size and exercise affects infarct size in rat after coronary artery cauterization.

Left coronary occlusion in the rat was performed by cornary artery cauterization. A small amount of myocardial damage at the site of occlusion was noted, and myocardial infarction occurred in the distal distribution of the obstructed coronary. The effects of cage size and level of physical activity on estimated infarct size (as measured by creatine kinase depletion) 48 h after occlusion were determined. Isolation in small cages and moderate treadmill exercise resulted in an approximate doubling of the amount of infarction when compared to grouping of rats in large cages. Mild exercise did not increase infarct size. Total urinary catecholamines in normal rats placed in small cages for 48 h were elevated when compared to unconfined rats in larger cages. Cornary artery occlusion by cauterization is an easily performed technique. Cage size and level of activity (and their effects on sympathoadrenal function) are important independent determinations of infarct extent after coronary occlusion in the rat.

Development of fighting behavior in mice: effects of experiential factors.

26 isolate-reared male mice show progressively shorter latencies to fight concomitant with weekly, brief social encounters. Subjects exposed to male peers showed shorter latencies than males exposed to female peers. Possible effects of cage size and/or visual experience are discussed. It is suggested that the effects of various life histories upon aggression be investigated.

Studies on the Housing Density of the Fowl

About twenty years have passed since the cage system for the layer was introduced into Japan. A high percentage of layers operation are utilizing cage system as a method of housing the bird. But there are a few reports concerning the effect of cage size and number of bird per cage. This study was done to obtain information of the effect of cage size and bird density in the cage on the performance of egg production type pullets.A most popullar individual laying cage size in Japan, is about 24cm width, 39cm depth and 40cm height.A total 249 commercial strain pullets (Babcock B 300) were confined in cage at 120 days of age under five treatments: birds were put in 18cm cage individually (Treatment 1), in 24cm cage individually (Treatment 2), two birds to 24cm cage (Treatment 3), two birds in 30cm cage (Treatment 4) and three birds in 48cm cage (Treatment 5). All cages were 39cm depth and 40cm height. Birds were debeaked by cutting off their both mandibles. Feeding experiment was conducted over the one year from 120 to 500 days of age.There were no differences in days to 50% egg production, percent of egg production on a hen day basis from 150 to 500 days of age, average number of eggs of survival hens and average egg weight among the treatments. Feed conversions of Treatment 4 and 5 were a little higher than other treatments, because of much feed intake. Mortality did not increased and cannibalism in high density treatment were not observed. Percent of cracked, brocken and stained shell egg were not differrent among the treatments.These results suggested the possibility of making higher housing density of cage laying house than that common in Japan.

Effects of cage population and stocking density on the performance of layers in Queensland

Three commercial egg production strains, a White Leghorn and two White Leghorn x Australorp, were used in two experiments which examined the effects of cage size and number of birds per cage on production characteristics. Nine cage housing systems varying from a 23 cm frontage single bird cage to a 61 cm frontage cage housing seven birds were compared. The efficacy of debeaking again at 12 or 20 weeks of age following routine debeaking at five days of age as a cannibalism control measure in a comparison of five housing systems was examined in another two experiments. Further experiments examined the practice of housing birds according to body weight in either one, two or three bird cage populations. Increasing bird numbers per cage or stocking density had little effect on egg weight, feed consumption or liveweight gain but decreased egg production and increased mortality in experiments where cannibalism was a significant cause of death. Hen housed egg production was an accurate measure of bird performance for comparison of housing systems. In experiments where additional debeaking was carried out the incidence of cannibalism was insignificant and debeaking at 12 or 20 weeks had no detrimental effect on bird performance. No strain x cage housing system interactions were observed and no improvement in performance resulted from housing birds in multiple bird cages according to liveweight.

Social isolation in young rats: Effects of cage size on open-field behavior

Locomotor activity of socially isolated male rats was found to be positively related to cage size, thereby suggesting that contradictory findings in previous studies comparing isolated with grouped animals may in part have been due to variations in isolates’ cage sizes.

Effect of Cage Size and Bird Density on Performance of Six Commercial Strains of Layers

THE trend toward housing egg-producing strains of chickens at high densities results from rising costs of buildings, equipment and labor. Cages are used more with birds housed at high densities. Logan (1965) reported if birds are to be housed at high densities cages should be used, while floor housing is advantageous for low densities.Effects of cage size, number of birds per cage, and bird density on performance of egg-producing birds have been widely studied (Shupe and Quisenberry, 1961; Lowe and Heywang, 1964; Moore et al., 1965; Cook and Dembnicki, 1966; Elmslie et al., 1966; Wilson et al., 1967; and Champion and Zindel, 1968). In general, egg production declined and mortality increased as bird population or bird density increased.Several researchers found that responses of layer strains differ significantly with various cage-size and bird-density environments (Gowe, 1956; Francis, 1957a; Cook and Dembnicki, 1966; Elmslie et al., 1966; Wilson et al.,…

Studies on the Housing Density of the Fowl

About twenty years have passed since the cage system for the layer was introduced into Japan. A high percentage of layers operation are utilizing cage system as a method of housing the bird. But there are a few reports concerning the effect of cage size and number of bird per cage. This study was done to obtain information of the effect of cage size and bird density in the cage on the performance of egg production type pullets.A most popullar individual laying cage size in Japan, is about 24cm width, 39cm depth and 40cm height.A total 249 commercial strain pullets (Babcock B 300) were confined in cage at 120 days of age under five treatments: birds were put in 18cm cage individually (Treatment 1), in 24cm cage individually (Treatment 2), two birds to 24cm cage (Treatment 3), two birds in 30cm cage (Treatment 4) and three birds in 48cm cage (Treatment 5). All cages were 39cm depth and 40cm height. Birds were debeaked by cutting off their both mandibles. Feeding experiment was conducted over the one year from 120 to 500 days of age.There were no differences in days to 50% egg production, percent of egg production on a hen day basis from 150 to 500 days of age, average number of eggs of survival hens and average egg weight among the treatments. Feed conversions of Treatment 4 and 5 were a little higher than other treatments, because of much feed intake. Mortality did not increased and cannibalism in high density treatment were not observed. Percent of cracked, brocken and stained shell egg were not differrent among the treatments.These results suggested the possibility of making higher housing density of cage laying house than that common in Japan.

Performance of Layers Under Various Cage Regimes

A HIGH percentage of layer operations are utilizing cages as the method of housing the birds. The advantages and disadvantages of cages as compared to floor methods have been studied by several workers (Hartman, 1953; Johnson and Zindel, 1962; Michalson, 1964; Sicer, 1964; Logan, 1965). Logan (1965) stated that if birds are to be crowded, cages should be used, while floor housing is advantageous for low density operations. Apparently certain strains of egg production type birds are better adapted to laying cage conditions than are others (Gowe, 1956; Francis, 1956).Two major decisions must be made when a cage system is installed: 1) the size of cage to use; and 2) the number of birds to be placed in each cage.Studies reporting the effects of cage size per se have been limited and the results inconclusive. The advantages and disadvantages of using multiple-bird cages have been reviewed previously (Bramhall …

Influence of Cage Size and Frightening on Incidence of Body Checked Eggs

Little is known concerning the cause of body checked eggs. Romanoff and Romanoff (1949) suggested that body checks might be caused by birds becoming excited or being handled roughly. In a recent study, Wilson and Jones (1964) found that the incidence of body checks was slightly higher with three birds per cage as compared to one bird per cage. The purpose of this paper is to present evidence of a cage size effect and frightening on the incidence of body checks. EXPERIMENTAL PROCEDURE AND RESULTSFive experiments were conducted concerning the effect of cage size on the incidence of body checks. One thousand White Leghorn pullets were used in the study, 600 of which were in 8″×18″ wire cages and 400 in 10″×18″ cages. Eggs were collected in filler flats the day they were laid and candled for body checks the next day with an incandescent light. Eggs were considered…

The Persistence of Some Effects of Handling in Infancy on the Behaviour of the Adult Rat

An attempt was made to discover how persistent the effects of handling before weaning are on activity, grooming, emotional elimination and learning in adult rats; whether there is an interaction of the effects of handling and the effects of cage size on the behaviour of rats; and whether the daily removal of the mother during nursing has any effects on the pups. Since all differences between handled and undisturbed animals found at 50 or 100 days were found at 220 days, it was concluded that the effects of handling in infancy are persistent. The hypothesis that cage size and removal of the mother during nursing significantly affect adult behaviour was not supported by the results.