This article was downloaded by: [New York University] On: 12 July 2015, At: 13:55 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: 5 Howick Place, London, SW1P 1WG
British Poultry Science Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/cbps20
The effect of continuous ultraviolet irradiation on broiler chickens a
K. C. Barnett & A. P. Laursen‐Jones
b
a
Comparative Ophthalmology Unit, Department of Veterinary Clinical Studies , University of Cambridge , Cambridge, England b
BOCM Silcock Limited , Basing View, Basingstoke, Hampshire, England Published online: 08 Nov 2007.
To cite this article: K. C. Barnett & A. P. Laursen‐Jones (1976) The effect of continuous ultraviolet irradiation on broiler chickens, British Poultry Science, 17:2, 175-177, DOI: 10.1080/00071667608416263 To link to this article: http://dx.doi.org/10.1080/00071667608416263
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/ terms-and-conditions
Br. Poult. Sci., 17: 175-177.
THE
1976
Longman:
printed in Great Britain
EFFECT OF CONTINUOUS ULTRAVIOLET IRRADIATION ON BROILER CHICKENS K. C. BARNETT
Comparative Ophthalmology Unit, Department of Veterinary Clinical Studies, University of Cambridge, Cambridge, England AND
Downloaded by [New York University] at 13:55 12 July 2015
A. P. LAURSEN-JONES BOCM Silcock Limited, Basing View, Basingstoke, Hampshire, England Received for publication 14th April 1975
1. Continuous ultraviolet irradiation (10.45 μW/cm2) did not affect the growth or food conversion efficiency of broilers. 2. The cornea of the eye was roughened by the treatment and there was a loss of the regular arrangement of the corneal cells: vision was not significantly affected after 49 d exposure. INTRODUCTION
Ultraviolet irradiation (UVI) has been recommended as a protective measure for chickens exposed to Newcastle disease virus (Perek and Heller, 1970). The authors also noted that the birds subjected to UVI grew at a greater rate in three out of four trials while the efficiency of food utilisation was significantly better than controls in all four trials. The objects of the present study, which consisted of two separate feeding trials, were to investigate the effects of UVI on performance in broilers and to note any adverse effects on the eye. The birds were not experimentally infected with Newcastle disease virus and on the basis of serological tests did not contract Newcastle disease during the course of the experiment.
MATERIALS AND METHODS
In each experiment, 3200 Ross broilers were reared in a controlled environment house which was subdivided into 24 pens each measuring 4 m x 2*5 m. Each pen was continuously illuminated with a 60-W bulb for the first five days and then with a 25-W bulb for 23 h in every 24 h. The pens were screened with black, light-proof paper which prevented the intrusion of UV light to the control pens. A commercial diet was fed ad libitum throughout the trial. A 30-W mercury vapour lamp, one metre in length, was suspended 2#2 m above 175
Downloaded by [New York University] at 13:55 12 July 2015
176
K. C. BARNETT AND A. P. LAURSEN-JONES
the floor in the centre of each of the 12 randomly selected pens. The irradiation levels ranged between 8-84 /iW/cm2 and 12-06 /xW/cm2 (mean, 10-45 ^W/cm2). Body weight, food consumption and mortality data were determined at 49 d and random samples of birds were examined for eye abnormalities at the end of both experiments. In the second experiment three birds were removed at 42 d from a pen irradiated with UV light and transferred to a control pen for the remaining 7d. The eyes of all birds were subjected to naked eye examination using a simple pen torch, a direct ophthalmoscope and a slit-lamp microscope. Immediately after death (intravenous barbiturate) of a random sample, eyes were enucleated and examined macroscopically and histologically following formol saline fixation and routine staining methods. The globe and periorbital region, the conjunctiva, cornea and anterior segment, lens and fundus were all examined. RESULTS AND DISCUSSION
Bird performance
Details of performance are given in Table 1. TABLE I Bird performancedata
Normal light Live-weight (g) Food intake (g) Food conversion (g food/g increase in body weight) Mortality (%)
Exp. 1 1713 3526 2-06
Exp. 2 2029 4204 2-07
3-46
5-00
UV light * Exp. 1 Exp.2 1701 2041 3575 4308 2-10 2-11 4-04
4-04
Least significant difference I[P = 0-05) 1
Exp. 1 45-9 70-67 0-04
Exp.2 41-9 64-6 0-04
...
Although Perek and Heller (1970) were primarily interested in UVI as a protective measure for chickens exposed to Newcastle disease virus, improvements in food conversion were consistently noted. The results of both experiments reported here failed to confirm the findings of Perek and Heller (1970). It is possible that the considerably larger groups showing a generally better performance overall were factors in this failure. Eye abnormalities
The only ocular change detected involved the cornea. The corneal surface is normally perfectly smooth and glistening (Plate-Fig. 1) but in birds exposed to UVI the surface was roughened and dull (Plate-Fig. 2). This change was best seen when viewing the corneal light reflex (reflection of the ophthalmoscope beam on the cornea) with a + 20 dioptre lens. The dullness of the cornea caused the fundus to appear less sharp when compared with that of control birds. The corneal change had no effect on vision and surprisingly the birds showed no evidence of an ocular irritation, such as blepharospasm or discharge. The post-mortem appearance of enucleated eyes was normal, there being no
Downloaded by [New York University] at 13:55 12 July 2015
PLATE-FIG. 1.—Control bird showing normal corneal reflection
PLATE-FIG. 2.-Affected bird showing irregular corneal light reflex indicating roughened corneal epithelium
Downloaded by [New York University] at 13:55 12 July 2015
EFFECTS OF UV IRRADIATION
177
difference in size of eyeball or corneal curvature as in the turkey blindness syndrome (Barnett et al, 1971). Histopathological changes in affected birds occurred at the limbus (corneoscleral junction) and in the cornea. The surface epithelium was generally rougher and in places small erosions had occurred. The epithelium was thicker and more acidophilic in staining reaction than that of the control birds with cornification and loss of the regular arrangement of the cells. Perinuclear oedema and pyknotic nuclei were present in the deeper layers. No difficulty was experienced in distinguishing between the birds subjected to UVI and the control birds. The group of birds which had been exposed to UVI for 42 d and then transferred to a control pen for the final 7 d showed no definite opthalmoscopic corneal changes but histologically there was evidence of pathological change. It is concluded therefore that UVI damages the corneal surface and does not result in improved performance. REFERENCES BARNETT, K. C., ASHTON, W. L. G., HOLFORD, J., MACPHERSON, I. AND SIMM, P. D. (1971).
Chorio-
retinitis and buphthalmos in turkeys. Vet. Rec., 88: 620-627. PEREK, M. AND HELLER, E. D. (1970). Ultraviolet irradiation as a protective measure for chicks exposed to Newcastle disease virus. Poult. Sci., 49: 1742-1744.
17/2—D
British Poultry Science Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/cbps20
The effect of continuous ultraviolet irradiation on broiler chickens a
K. C. Barnett & A. P. Laursen‐Jones
b
a
Comparative Ophthalmology Unit, Department of Veterinary Clinical Studies , University of Cambridge , Cambridge, England b
BOCM Silcock Limited , Basing View, Basingstoke, Hampshire, England Published online: 08 Nov 2007.
To cite this article: K. C. Barnett & A. P. Laursen‐Jones (1976) The effect of continuous ultraviolet irradiation on broiler chickens, British Poultry Science, 17:2, 175-177, DOI: 10.1080/00071667608416263 To link to this article: http://dx.doi.org/10.1080/00071667608416263
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/ terms-and-conditions
Br. Poult. Sci., 17: 175-177.
THE
1976
Longman:
printed in Great Britain
EFFECT OF CONTINUOUS ULTRAVIOLET IRRADIATION ON BROILER CHICKENS K. C. BARNETT
Comparative Ophthalmology Unit, Department of Veterinary Clinical Studies, University of Cambridge, Cambridge, England AND
Downloaded by [New York University] at 13:55 12 July 2015
A. P. LAURSEN-JONES BOCM Silcock Limited, Basing View, Basingstoke, Hampshire, England Received for publication 14th April 1975
1. Continuous ultraviolet irradiation (10.45 μW/cm2) did not affect the growth or food conversion efficiency of broilers. 2. The cornea of the eye was roughened by the treatment and there was a loss of the regular arrangement of the corneal cells: vision was not significantly affected after 49 d exposure. INTRODUCTION
Ultraviolet irradiation (UVI) has been recommended as a protective measure for chickens exposed to Newcastle disease virus (Perek and Heller, 1970). The authors also noted that the birds subjected to UVI grew at a greater rate in three out of four trials while the efficiency of food utilisation was significantly better than controls in all four trials. The objects of the present study, which consisted of two separate feeding trials, were to investigate the effects of UVI on performance in broilers and to note any adverse effects on the eye. The birds were not experimentally infected with Newcastle disease virus and on the basis of serological tests did not contract Newcastle disease during the course of the experiment.
MATERIALS AND METHODS
In each experiment, 3200 Ross broilers were reared in a controlled environment house which was subdivided into 24 pens each measuring 4 m x 2*5 m. Each pen was continuously illuminated with a 60-W bulb for the first five days and then with a 25-W bulb for 23 h in every 24 h. The pens were screened with black, light-proof paper which prevented the intrusion of UV light to the control pens. A commercial diet was fed ad libitum throughout the trial. A 30-W mercury vapour lamp, one metre in length, was suspended 2#2 m above 175
Downloaded by [New York University] at 13:55 12 July 2015
176
K. C. BARNETT AND A. P. LAURSEN-JONES
the floor in the centre of each of the 12 randomly selected pens. The irradiation levels ranged between 8-84 /iW/cm2 and 12-06 /xW/cm2 (mean, 10-45 ^W/cm2). Body weight, food consumption and mortality data were determined at 49 d and random samples of birds were examined for eye abnormalities at the end of both experiments. In the second experiment three birds were removed at 42 d from a pen irradiated with UV light and transferred to a control pen for the remaining 7d. The eyes of all birds were subjected to naked eye examination using a simple pen torch, a direct ophthalmoscope and a slit-lamp microscope. Immediately after death (intravenous barbiturate) of a random sample, eyes were enucleated and examined macroscopically and histologically following formol saline fixation and routine staining methods. The globe and periorbital region, the conjunctiva, cornea and anterior segment, lens and fundus were all examined. RESULTS AND DISCUSSION
Bird performance
Details of performance are given in Table 1. TABLE I Bird performancedata
Normal light Live-weight (g) Food intake (g) Food conversion (g food/g increase in body weight) Mortality (%)
Exp. 1 1713 3526 2-06
Exp. 2 2029 4204 2-07
3-46
5-00
UV light * Exp. 1 Exp.2 1701 2041 3575 4308 2-10 2-11 4-04
4-04
Least significant difference I[P = 0-05) 1
Exp. 1 45-9 70-67 0-04
Exp.2 41-9 64-6 0-04
...
Although Perek and Heller (1970) were primarily interested in UVI as a protective measure for chickens exposed to Newcastle disease virus, improvements in food conversion were consistently noted. The results of both experiments reported here failed to confirm the findings of Perek and Heller (1970). It is possible that the considerably larger groups showing a generally better performance overall were factors in this failure. Eye abnormalities
The only ocular change detected involved the cornea. The corneal surface is normally perfectly smooth and glistening (Plate-Fig. 1) but in birds exposed to UVI the surface was roughened and dull (Plate-Fig. 2). This change was best seen when viewing the corneal light reflex (reflection of the ophthalmoscope beam on the cornea) with a + 20 dioptre lens. The dullness of the cornea caused the fundus to appear less sharp when compared with that of control birds. The corneal change had no effect on vision and surprisingly the birds showed no evidence of an ocular irritation, such as blepharospasm or discharge. The post-mortem appearance of enucleated eyes was normal, there being no
Downloaded by [New York University] at 13:55 12 July 2015
PLATE-FIG. 1.—Control bird showing normal corneal reflection
PLATE-FIG. 2.-Affected bird showing irregular corneal light reflex indicating roughened corneal epithelium
Downloaded by [New York University] at 13:55 12 July 2015
EFFECTS OF UV IRRADIATION
177
difference in size of eyeball or corneal curvature as in the turkey blindness syndrome (Barnett et al, 1971). Histopathological changes in affected birds occurred at the limbus (corneoscleral junction) and in the cornea. The surface epithelium was generally rougher and in places small erosions had occurred. The epithelium was thicker and more acidophilic in staining reaction than that of the control birds with cornification and loss of the regular arrangement of the cells. Perinuclear oedema and pyknotic nuclei were present in the deeper layers. No difficulty was experienced in distinguishing between the birds subjected to UVI and the control birds. The group of birds which had been exposed to UVI for 42 d and then transferred to a control pen for the final 7 d showed no definite opthalmoscopic corneal changes but histologically there was evidence of pathological change. It is concluded therefore that UVI damages the corneal surface and does not result in improved performance. REFERENCES BARNETT, K. C., ASHTON, W. L. G., HOLFORD, J., MACPHERSON, I. AND SIMM, P. D. (1971).
Chorio-
retinitis and buphthalmos in turkeys. Vet. Rec., 88: 620-627. PEREK, M. AND HELLER, E. D. (1970). Ultraviolet irradiation as a protective measure for chicks exposed to Newcastle disease virus. Poult. Sci., 49: 1742-1744.
17/2—D
