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The Effect of Light on Body Weight and Feed Conversion of Broilers
1350
RESEARCH NOTES
1961b. Groundnut toxicity. Vet. Rec. 73: 865. Sargent, K., and J. O'Kelly, R. B. A. Carnaghan and R. Allcroft, 1961a. Letters to Editor. Vet. Rec. 73 : 428.
Sargent, K., A. Sheridan and J. O'Kelly, 1961c. Letters to Editor. Nature 192: 1096-1097. Siller, W. G., and D. C. Ostler, 1961. Letters to Editor. Vet. Rec. 73: 134.
THE EFFECT OF LIGHT ON BODY WEIGHT AND FEED CONVERSION OF BROILERS W.
L. BEANE, P. B. SIEGEL AND H.
S. SIEGEL
Virginia Agricultural Experiment Station, Blacksburg (Received for publication March 20, 1962)
1.5 linear inches per chick started to 3 weeks of age and 3.0 inches per bird thereafter. A commercial broiler mash was fed throughout. Individual body weights and feed consumptions by pen were obtained at 3, 6 and 9 weeks of age. In Trial 1, which was carried out during relatively warm weather (August-October), birds receiving continuous light were significantly heavier at all 3 weight periods than those under the other light regimes (Table 1); they also had the poorest feed conversion. Results of Trial 2, which was carried out during colder weather (November-January), indicated no significant body weight differences between those birds receiving continuous light and those receiving the 1 :2 treatment at 3 and 6 weeks of age. However, at 9 weeks of age the birds grown TABLE 1.—Means+S.D. of body weights and feed conversions1 Period (wks.)
Light Treatments (Consecutive Hours on:off) 24:0 8:16 1:2
1
0-3 0-6 0-9
Body Weights (grams) 323+ 39" 294+ 32b 300+ 37 b 950+106" 887+ 8<* 903 ± 99bb b 1,746±204" l,694±I72 l,684±177
2
0-3 0-6 0-9
322+ 33" 972+ 89" 1,770+145"
1
0-3 0-6 0-9
Feed Conversions (feed/gain) 1.70+ .05" 1.61+ .04 b 1.62+ .04 b 1.96+ .06" 1.94+ .03" 1.95+ .02" 2.32+ .04" 2.24+ .04 b 2.26+ .04 b
2
0-3 0-6 0-9
1.65+ .05" 1.99+ .05" 2.36+ .02"
283+ 32bb 885+102 1,661+163°
1.58+ .03 b 2.00± .04" 2.34+ .03"
327± 36" 959+102" 1,726+ 178b
1.54+ .04 b 1.94+ .04" 2.36+ .03"
1 Any 2 values on the same horizontal having the same superscript are not significantly different.
Downloaded from http://ps.oxfordjournals.org/ at Ritsumeikan University on June 14, 2015
The body weights of 7 to 9 month-old White Leghorn males were observed by Lamoreux (1943) to be significantly greater when light was restricted to less than 9 hours per day. Siegel et al. (1961) reported significantly heavier body weights and better feed conversion in White Leghorn pullets at 8 weeks of age when restricting light to 6 hours per day compared to 14 hours of light per day. In a study with broiler chickens, Moore (1957) found that faster growth was obtained up to 3 or 4 weeks of age with continuous light although feed efficiency was slightly better with less light throughout the growing period. A series of experiments reported by Shutze et al. (1960) indicated that birds exposed to continuous light were superior in body weight gain to those on the other light regimes with the exception of one experiment in which chick growth response to 2 hour light : 2 hours darkness was about equal to that with continuous light. In the study reported herein, the effect of continuous light, 8 hours light: 16 hours darkness, and 1 hour light: 2 hours darkness on broiler body weights and feed conversion was determined in two successive trials beginning August 21, 1961 and ending January 2, 1962. Four replicated pens of 120 commercial broiler male chicks were used in each treatment with a total of 1440 birds used in each of the two trials. Trough type feeders were used, allowing
RESEARCH NOTES
under continuous light were significantly heavier. Those birds receiving 8 hours light : 16 hours darkness weighed significantly less throughout. There were no differences between treatments for feed conversion in Trial 2 after the 3rd week. REFERENCES Lamoreux, W. F., 1943. The influence of different amounts of illumination upon body weight of birds. Ecology, 24: 79-84.
1351
Moore, C. H., 1957. The effect of light on growth of broiler chickens. Poultry Sci. 36: 1142-1143. Shutze, J. V., L. S. Jensen, J. S. Carver and W. E. Matson, 1960. Influence of various lighting regimes on the performance of growing chickens. Washington Agr. Exp. Sta. Tech. Bui. No. 36. Siegel, H. S., W. L. Beane and C. E. Howes, 1961. The influence of two light management systems on the growth and production of commercial layers. Virginia Agr. Expt. Sta. Res. Rpt. 54.
R. D. CREEK AND VALERIA VASAITIS Poultry Department, The University of Maryland, College Park (Received for publication March 22, 1962)
R
ECENT work from this station has • demonstrated that raw wheat germ is detrimental to growth of young chicks, and markedly interferes with the absorption of fat (Creek et al., 1961a, b). These effects are reversed by autoclaving. The behavior of the raw wheat germ is very similar to that of raw soybeans which contain an antitrypsin factor (Brambila et al., 1961). In view of this similarity it was decided to test wheat germ for the presence of factors which inhibit proteolytic enzymes. EXPERIMENTAL AND RESULTS
The two samples of wheat germ used in this work were obtained from different commercial companies, and intended for feed grade use. The extraction and assay procedures used were identical to those of Bowman (1944) except for digestion time. Preliminary work indicated that the water extract of wheat germ contained a factor which inhibited the enzymatic di1 Scientific Article No. A97o Contribution No. 3351 of the Maryland Agricultural Experiment Station (Department of Poultry Husbandry).
gestion of casein and the water soluble protein in the extract. The possibility that indigestibility of wheat germ protein within the extract could account for the differences noted was eliminated by digestion in the absence of casein. Typical results obtained are found in Table 1 and show clearly that the wheat germ extract inhibits proteolysis. Its inhibitory effect was destroyed by autoclaving.
TABLE 1.—Percent protein digested by pancreatin at various time intervals1-*
1
Treatment
30 Min.
Control Wheat germ extract (raw) 3 Wheat germ extract (autoclaved) 4
53.10
74 Min. 111 Min. 73.74
74.70
27.61
52.46
58.59
45.62
64.66
70.80
Control Wheat germ extract (raw)s Wheat germ extract (autoclaved) 4
43.32
72.83
76.70
25.60
51.19
59.52
43.52
68.52
72.84
Pancreatin was obtained from Nutritional Biochemicals Corporation, Cleveland, Ohio. 8 Vitamin free casein (Nutritional Biochemicals Corporation) was the protein substrate. 3 Extract was made by diluting 1 gram of wheat germ to 100 ml. with distilled water. Ten ml. of the extract was used in each assay. 4 Extract was obtained as in footnote 3, then autoclaved for 45 minutes at 15 psi and 121° centigrade.
Downloaded from http://ps.oxfordjournals.org/ at Ritsumeikan University on June 14, 2015
DETECTION OF AN ANTI-PROTEOLYTIC SUBSTANCE IN RAW WHEAT GERM 1
RESEARCH NOTES
1961b. Groundnut toxicity. Vet. Rec. 73: 865. Sargent, K., and J. O'Kelly, R. B. A. Carnaghan and R. Allcroft, 1961a. Letters to Editor. Vet. Rec. 73 : 428.
Sargent, K., A. Sheridan and J. O'Kelly, 1961c. Letters to Editor. Nature 192: 1096-1097. Siller, W. G., and D. C. Ostler, 1961. Letters to Editor. Vet. Rec. 73: 134.
THE EFFECT OF LIGHT ON BODY WEIGHT AND FEED CONVERSION OF BROILERS W.
L. BEANE, P. B. SIEGEL AND H.
S. SIEGEL
Virginia Agricultural Experiment Station, Blacksburg (Received for publication March 20, 1962)
1.5 linear inches per chick started to 3 weeks of age and 3.0 inches per bird thereafter. A commercial broiler mash was fed throughout. Individual body weights and feed consumptions by pen were obtained at 3, 6 and 9 weeks of age. In Trial 1, which was carried out during relatively warm weather (August-October), birds receiving continuous light were significantly heavier at all 3 weight periods than those under the other light regimes (Table 1); they also had the poorest feed conversion. Results of Trial 2, which was carried out during colder weather (November-January), indicated no significant body weight differences between those birds receiving continuous light and those receiving the 1 :2 treatment at 3 and 6 weeks of age. However, at 9 weeks of age the birds grown TABLE 1.—Means+S.D. of body weights and feed conversions1 Period (wks.)
Light Treatments (Consecutive Hours on:off) 24:0 8:16 1:2
1
0-3 0-6 0-9
Body Weights (grams) 323+ 39" 294+ 32b 300+ 37 b 950+106" 887+ 8<* 903 ± 99bb b 1,746±204" l,694±I72 l,684±177
2
0-3 0-6 0-9
322+ 33" 972+ 89" 1,770+145"
1
0-3 0-6 0-9
Feed Conversions (feed/gain) 1.70+ .05" 1.61+ .04 b 1.62+ .04 b 1.96+ .06" 1.94+ .03" 1.95+ .02" 2.32+ .04" 2.24+ .04 b 2.26+ .04 b
2
0-3 0-6 0-9
1.65+ .05" 1.99+ .05" 2.36+ .02"
283+ 32bb 885+102 1,661+163°
1.58+ .03 b 2.00± .04" 2.34+ .03"
327± 36" 959+102" 1,726+ 178b
1.54+ .04 b 1.94+ .04" 2.36+ .03"
1 Any 2 values on the same horizontal having the same superscript are not significantly different.
Downloaded from http://ps.oxfordjournals.org/ at Ritsumeikan University on June 14, 2015
The body weights of 7 to 9 month-old White Leghorn males were observed by Lamoreux (1943) to be significantly greater when light was restricted to less than 9 hours per day. Siegel et al. (1961) reported significantly heavier body weights and better feed conversion in White Leghorn pullets at 8 weeks of age when restricting light to 6 hours per day compared to 14 hours of light per day. In a study with broiler chickens, Moore (1957) found that faster growth was obtained up to 3 or 4 weeks of age with continuous light although feed efficiency was slightly better with less light throughout the growing period. A series of experiments reported by Shutze et al. (1960) indicated that birds exposed to continuous light were superior in body weight gain to those on the other light regimes with the exception of one experiment in which chick growth response to 2 hour light : 2 hours darkness was about equal to that with continuous light. In the study reported herein, the effect of continuous light, 8 hours light: 16 hours darkness, and 1 hour light: 2 hours darkness on broiler body weights and feed conversion was determined in two successive trials beginning August 21, 1961 and ending January 2, 1962. Four replicated pens of 120 commercial broiler male chicks were used in each treatment with a total of 1440 birds used in each of the two trials. Trough type feeders were used, allowing
RESEARCH NOTES
under continuous light were significantly heavier. Those birds receiving 8 hours light : 16 hours darkness weighed significantly less throughout. There were no differences between treatments for feed conversion in Trial 2 after the 3rd week. REFERENCES Lamoreux, W. F., 1943. The influence of different amounts of illumination upon body weight of birds. Ecology, 24: 79-84.
1351
Moore, C. H., 1957. The effect of light on growth of broiler chickens. Poultry Sci. 36: 1142-1143. Shutze, J. V., L. S. Jensen, J. S. Carver and W. E. Matson, 1960. Influence of various lighting regimes on the performance of growing chickens. Washington Agr. Exp. Sta. Tech. Bui. No. 36. Siegel, H. S., W. L. Beane and C. E. Howes, 1961. The influence of two light management systems on the growth and production of commercial layers. Virginia Agr. Expt. Sta. Res. Rpt. 54.
R. D. CREEK AND VALERIA VASAITIS Poultry Department, The University of Maryland, College Park (Received for publication March 22, 1962)
R
ECENT work from this station has • demonstrated that raw wheat germ is detrimental to growth of young chicks, and markedly interferes with the absorption of fat (Creek et al., 1961a, b). These effects are reversed by autoclaving. The behavior of the raw wheat germ is very similar to that of raw soybeans which contain an antitrypsin factor (Brambila et al., 1961). In view of this similarity it was decided to test wheat germ for the presence of factors which inhibit proteolytic enzymes. EXPERIMENTAL AND RESULTS
The two samples of wheat germ used in this work were obtained from different commercial companies, and intended for feed grade use. The extraction and assay procedures used were identical to those of Bowman (1944) except for digestion time. Preliminary work indicated that the water extract of wheat germ contained a factor which inhibited the enzymatic di1 Scientific Article No. A97o Contribution No. 3351 of the Maryland Agricultural Experiment Station (Department of Poultry Husbandry).
gestion of casein and the water soluble protein in the extract. The possibility that indigestibility of wheat germ protein within the extract could account for the differences noted was eliminated by digestion in the absence of casein. Typical results obtained are found in Table 1 and show clearly that the wheat germ extract inhibits proteolysis. Its inhibitory effect was destroyed by autoclaving.
TABLE 1.—Percent protein digested by pancreatin at various time intervals1-*
1
Treatment
30 Min.
Control Wheat germ extract (raw) 3 Wheat germ extract (autoclaved) 4
53.10
74 Min. 111 Min. 73.74
74.70
27.61
52.46
58.59
45.62
64.66
70.80
Control Wheat germ extract (raw)s Wheat germ extract (autoclaved) 4
43.32
72.83
76.70
25.60
51.19
59.52
43.52
68.52
72.84
Pancreatin was obtained from Nutritional Biochemicals Corporation, Cleveland, Ohio. 8 Vitamin free casein (Nutritional Biochemicals Corporation) was the protein substrate. 3 Extract was made by diluting 1 gram of wheat germ to 100 ml. with distilled water. Ten ml. of the extract was used in each assay. 4 Extract was obtained as in footnote 3, then autoclaved for 45 minutes at 15 psi and 121° centigrade.
Downloaded from http://ps.oxfordjournals.org/ at Ritsumeikan University on June 14, 2015
DETECTION OF AN ANTI-PROTEOLYTIC SUBSTANCE IN RAW WHEAT GERM 1