- Email: [email protected]
Effect of Tung Meal in Rations for Growing Chicks
Effect of Tung Meal in Rations for Growing Chicks GEORGE K. DAVIS AND N. R. M E H R H O F Nutrition and Poultry Laboratories, Animal Industry Department, Florida Agricultural Experiment Station AND R . S. M c K l N N E Y Agricultural Chemical Research Division, Bureau of Agricultural and Industrial Chemistry, United States Department of Agriculture (Received for publication, September 4, 1945)
passed through a 40 mesh screen to remove the larger particles of shell.
UNG meal or ground tung press cake is a by-product of the production of tung oil from tung nuts v The protein content of this product is such that if it could be rendered safe it might possibly serve as a protein supplement in livestock and poultry feeds. The toxicity of tung meal has been noted by Lewkowitsch (i°09), Newell (1924), Davis (1940), and Sanders, Emmel and Henley (1933), and the possibility that this toxic property might be removed rendering the tung meal suitable for chicken rations has been suggested by the work of Rusoff, Mehrhof and McKinney (1942) and by Anderson (1942). In reviewing the work of Rusoff, Mehrhof and McKinney (1942) where solvent extracted meal was used, one of the authors (McK.) felt that possibly the heat treatment incident to the removal of the solvent was responsible for the destruction of the toxic principle. Since heat treatment is a process which could be rather readily applied to the tung meal now commercially available, the present experiment was set up to test tung meal processed by heating without solvent extraction. In order to test the possibility that the shell particles were responsible for part or all of the irritation of the intestinal mucosa, as noted by Godden (1933), part of the tung meal was
EXPERIMENTAL PROCEDURES ,
The raw tung meal was obtained from American Tung Oil Mills, Inc., Brooker, Florida, and was from freshly prepared tung press cake. Heat treatment was carried out by the U.S.D.A. Tung Oil Laboratory, Gainesville. The treatment consisted of adjusting the moisture of tung meal to IS.5 percent and of heating in an autoclave at 1 1 | pounds pressure, 115.5°C., for 90 minutes. After drying, a portion of the heat treated tung meal was passed through a 40 mesh screen. The portion which had the coarser particles of shell removed in this manner (38.3%) was the heat treated sifted tung meal included in the rations of lots 4 and 5. Raw tung meal was included in the experiment to provide a check on the effectiveness of the heat treatment, and to provide specimens of typical tung meal poisoning. An analysis of the tung meals used is given in Table 1. Eight lots of 25 S. C. White Leghorn chicks each were placed on experiment in individual wire mesh bottom brooders at two days of age. The composition of the basal ration is shown in Table 2, and that of the experimental rations is shown in 74
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
T
75
TUNG MEAL IN RATIONS FOR GROWING CHICKS TABLE 1.—Analysis of tung meals used
Tung meal
Treatment
Moisture
Protein (Nitrogen X6.25)
Ether extract
Crude fiber
Ash
Raw Press Cake Heated Press Cake Heated & Sieved Press Cake Heated Press Cake
1 2 3 4
6.2 9.9 9.8 9.6
22.71 21.56 32.28 23.38
1.27 1.25 1.47 1.21
33.81 30.74 11.93 30.55
5.59 5.26 7.42 5.30
N. F. E. 30.42 31.29 37.10 29.96
Treatment 1. Not processed. 2. Heated in an autoclave, 1J hours at 115.5° C. (240° F.) and 11.5 lbs. per sq. in. pressure. 3. Heated (as No. 2) and sieved on 40 mesh sieve. The 38.3 percent passing the 40 mesh sieve was used as Feed No. 3. 4. Heated in autoclave 1J hours at 128° C. (262.4° F.) and 22 lbs. per sq. in. pressure. TABLE 2.—Basal ration Pounds 360 70 30 50 30 30 60 30 20 10 10 57 gms. 90 gms.
Yellow corn meal Ground wheat Bran (wheat) Ground oats Meat scrap Whey Alfalfa leaf meal Produlac Bone meal Shell (oyster) Salt (NaCl) Manganese sulphate (MnSCu) Delsterol
TABLE 3.—Experimental rations and average weight of chicks in grams
Lot
Level of tung meal* Percent
Basal ration Percent
S.B.O.M4 Percent
Initial weight
1 2 3 4 5 6 7 8
0 5 10 5 10 5 10 15
70.0 68.3 66.6 69.0 68.0 67.8 65.6 63.4
30.0 26.7 23.4 26.0 22.0 27.2 24.4 21.6
35.6 36.6 35.5 36.8 33.4 37.1 33.4 36.4
Lot 1 9
0 15 -
70.0 63.4
30.0 21.6
Final weight adj. for sex infiu.
Feed utilization gms. feed/gm. gain
365.0 273.3 248.3 232.7
1.91 2.72 3.60 3.41
281.3
t t
2.73
3 wks. weight
10 wks. weight
Utilization 3 to 10 wks. gms. feed/gm.
164.5 101.8
863.4 532.3
Final weight 5 wks. 365.7 280.2 240.1 213.8 155.5 281.3 193.4
t
t t
'
3.65 5.85
* Lots 2 and 3 received unsifted heat treated tung meal, lots 4 and 5 received sifted heat treated tung meal, lots 6, 7 and 8 received raw tung meal and lot 9 received unsifted tung meal heated at 22 pound steam pressure. t Weights for lots 5 and 7 were not adjusted and feed utilization was not calculated because of high mortality. All chicks in lot 8 were dead at 4 weeks. | Soybean oil meal.
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
Table 3. The ration fed lot 1 is the same as that fed to the growing chicks of the University flock and is known to give good results. Lots 2, 4, and 6 received 5 percent and lots 3, 5, and 7 received 10 percent of the heat treated, heat treated sifted, and raw tung meals respectively. Lot number 8 received 15 percent raw tung meal. The quantity of soybean oil meal was adjusted to provide rations containing as nearly as possible 20 percent protein.
76
GEORGE K. DAVIS, N. R. MEHRHOF AND R. S. MCKINNEY TABLE 4.—Mortality of chicks by weeks Number of Chicks Dead
Lot 1 2 3 4 5 6 7 8 9
Week 1 2 3 4 5 Total 6 7 8 9 10 Total 0 0 2 0 3 1 1 3
0 0 0 0 0 0 0 0 1 0 0 0 1 1 2 2 2 12 9 2 0 0 2 4 4 5 8 3 23 0 0 0 0 1 S 7 0 4 17 11 8 3 25 1 1 2 3 2*
1
9
* Moribund.
RESULTS
The immediate reaction to the,feeding of all the tung meal rations was a severe diarrhea in the chicks receiving these rations. The droppings were very wet and foul smelling. The chicks soon became very dirty and feathers, as they developed, possessed an unnatural waxy feel. The diarrhea soon resulted in caking of
Beak and legs discolored, blue; vent dry and clean, but blue; crop nearly empty; severe ascites; subcutaneous tissues jaundiced; large areas of necrosis apparent on surface of liver; adhesions on liver indicative of inflammation; intestines full, lungs normal, gizzard full of feed about 50 percent tung shell. Other tissues and organs normal. Figures 1 and 2 show liver damage. In the chicks from lots receiving the raw tung meal and unsifted heat treated tung meal a frequent finding was a gizzard and intestinal tract with practically no other feed than tung shell. Presumably the chicks had picked out the dark pieces of shell preferentially. However, no inflammation of the gastro-intestinal tract was discovered in any of the chicks. During the first 3 weeks that lot 9 was on the experimental ration, the chicks grew at a rate comparable to that of the lots receiving 5 percent tung meal. However, there developed a waxy feel to their
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
Feed and water were kept before the chicks at all times and feed consumption measured weekly. All chicks were weighed at one week intervals. The mortality which developed early in the experiment on the heat treated tung meal caused a reevaluation to be made of the treatment and a second batch of tung meal was autoclaved at a temperature of 128°C. and 22 pounds pressure. There had been 23 chicks kept on the basal ration alone for such a contingency and at the beginning of the fourth week of the experiment lot 9 was started on a ration comparable to that given lot 8, but containing 15 percent of the special heat treated tung meal. This tung meal heated at the higher temperature and pressure for If hours had a dark brown, partially scorched appearance. Post mortem examinations were made on all chicks which died during the experiment and on several killed at the end of the experiment for comparative observation.
many of the vents and the first chicks to die showed apparent obstruction of the lower large intestine. Mortality records by weeks are shown in Table 4. It will be noted that the heaviest mortality was in the lots receiving the higher percentages of tung meal. After the first week the characteristic postmortem picture was one of liver damage and related pathology. Before death the legs and beak became bluish in color, indicative of cyanosis. In later instances, the skin over the abdomen frequently took on a bluish cast. Jaundice and ascites were usual findings after the second week on experiment. The gall bladder became greatly enlarged approaching the liver in size. Adhesions on the surface of the liver, indicating inflammation, were frequent and areas of massive necrosis within the liver were usual. A typical autopsy observation follows: (G-1551).
T U N G M E A L IN R A T I O N S FOR G R O W I N G C H I C K S
feathers and during the 3rd week on this ration and 6th of the experiment, mortality began to develop and by the 10th week of the experiment 7 of the 23 chicks were dead and 2 others moribund. On autopsy these chicks gave typical evidence of tung meal poisoning with gall bladder enlargement and characteristic damages to the body tissues associated with liver malfunction.
parent. At the 5 percent levels of tung meal, 2.72, 3.41 and 2.73 grams of feed were required to produce a gram of gain as compared to 1.91 grams of feed for lot 1 which received no tung meal. The inter-
FIG. 1. Liver from chick G1583 receiving IS percent raw tung meal. Note enlarged gall bladder and degenerated surface area.
ference with feed utilization is also evident in the results obtained with lot 9 as compared with lot 1. Although these chicks
FIG. 2. Livers from chick G1503 (left) on 10 percent heat treated and sieved tung meal and chick G1423 (right) on control ration. Note: These livers are in same relative position. While only the tip of the gall bladder shows below the liver of the control (just above the little finger), the gall bladder of the other chick is nearly one-half the size of the liver itself (just above the middle finger).
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
None of the tung meal lots gained as well as the control lot (#1). I n Table 3 the average weights at the beginning and a t the end of five weeks are shown for lots 1, 2, 3, 4, 5, 6 and 7. I n order to give a better comparison of lots 2, 4 and 6 receiving the 5 percent levels of tung meal the average weights were adjusted to take into account the fact t h a t lot 4 had a disproportionately large number of pullets. Table 3 also shows t h a t tung meal interfered with the utilization of the feed at the levels where toxicity was not so ap-
77
78
GEORGE K. DAVIS, N. R. MEHRHOF AND R. S. MCKINNEY
were thrifty and vigorous at three weeks of age they were considerably lighter in weight than the controls because of the low protein basal ration. The records show that lot 9 required 5.85 grams of feed compared to 3.65 grams for lot 1 to produce a gram of gain in the period from three to ten weeks of age. DISCUSSION
SUMMARY
1. Eight lots of 2 day old chicks were fed 0, 5, 10, and 15 percent levels of tung meal and one additional lot of 3 weeks old chicks was fed a 15 per cent level of tung meal to investigate its possible use as a source of protein in poultry rations. 2. The tung meal proved toxic whether raw, heated, or heated and sifted and caused heavy mortality at 10 and 15 percent levels. 3. At 5 percent and higher levels the tung meals interfered with feed utilization. 4. Tung meal, raw or autoclaved at 115.5°C. and 11.5 pounds pressure or at
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
The results of this experiment have demonstrated the toxicity of raw tung meal for chicks as has been noted by others. The tung meal which had been heated at 11.5 pounds pressure and 115.5°C. in the autoclave appeared to be as toxic as the raw tung meal. The relative toxicity of the heated tung meal which had been passed through a 40 mesh sieve was greater than either the raw or the heated unsifted tung meal. This finding would seem to indicate that the toxic principle of tung meal was more concentrated in the kernel. The tung shell did not cause obvious injury to the intestinal tract of the chicks, but the tendency of the chicks to pick out the shell to the exclusion of the other feed was an objectionable feature. At the 15 percent level of the raw tung meal the chicks were all dead at the end of four weeks except one which was killed in a moribund condition. At 5 weeks two chicks were left in lot 5 receiving the 10 percent sifted tung meal. One of these was moribund and extremely jaundiced. Those lots receiving 5 percent of the different tung meals did not suffer excessive mortality but the deleterious effect of its inclusion in the ration was evidenced by the lower rate of gain and by the poorer utilization of feed. All of these chicks had a waxy feel to the feathers which may have been indicative of some toxic reaction. From these results, it would appear
that the heat treatment used did not destroy the toxic principle of the tung meal. Furthermore the presence of tung meal in the rations at a level of 5 percent interfered with the utilization of the feed even though excess mortality was not encountered. Considering that the chicks in lot 9 were placed on the special heat treated tung meal at the age of 3 weeks, and therefore passed the period in which a heavy mortality occurred in some of the lots receiving this material and were presumably better able to resist toxic effects of the feed, it seems reasonable to assume that the tung meal, even though treated at the higher temperature, was relatively as toxic as the tung meal treated at the lower temperature. On the basis of results obtained in this experiment, it is apparent that heat treatment with a temperature as high as 262°F. and 22 pounds pressure is not sufficient to inactivate the toxic principle in tung meal. Because the higher temperature used caused a scorched product, it would seem very doubtful that tung meal can be rendered safe and suitable as a feed by heat treatment alone.
TUNG MEAL IN RATIONS FOR GROWING CHICKS
128°C. and 22 pounds pressure is not safe for use in chick feeds. BIBLIOGRAPHY
Anderson, E. M., 1942. Unpublished Work Poultry Laboratories, Animal Industry Dept. Univ. of Florida. Davis, H. J., 1940. Unpublished work. An. Industry Department, La. State University. Godden, W., 1933. The feeding value of tung-seed meal. Reprint. Bui. Imperial Institute 30: No. 3. Lewkowitsch, J. I., 1909. Chemical technology and
79
analysis of oils, fats and waxes. 4th edition McMillan and Company, London 2: p. 60. Newell, W., 1924. Preliminary report on experiments with the tung^oil tree in Florida. Florida Agr. Exp. Sta. Bui. 171. Sanders, D. A., M. W. Emmel and W. W. Henley, 1933. Unpublished work. An. Ind. Dept., Florida Agr. Exp. Station. Rusoff, L. L., N. R. Mehrhof and R. S. McKinney, 1942. Chick feeding experiments with solventextracted tung oil meal. Poultry Science 21:451454.
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
"J*
passed through a 40 mesh screen to remove the larger particles of shell.
UNG meal or ground tung press cake is a by-product of the production of tung oil from tung nuts v The protein content of this product is such that if it could be rendered safe it might possibly serve as a protein supplement in livestock and poultry feeds. The toxicity of tung meal has been noted by Lewkowitsch (i°09), Newell (1924), Davis (1940), and Sanders, Emmel and Henley (1933), and the possibility that this toxic property might be removed rendering the tung meal suitable for chicken rations has been suggested by the work of Rusoff, Mehrhof and McKinney (1942) and by Anderson (1942). In reviewing the work of Rusoff, Mehrhof and McKinney (1942) where solvent extracted meal was used, one of the authors (McK.) felt that possibly the heat treatment incident to the removal of the solvent was responsible for the destruction of the toxic principle. Since heat treatment is a process which could be rather readily applied to the tung meal now commercially available, the present experiment was set up to test tung meal processed by heating without solvent extraction. In order to test the possibility that the shell particles were responsible for part or all of the irritation of the intestinal mucosa, as noted by Godden (1933), part of the tung meal was
EXPERIMENTAL PROCEDURES ,
The raw tung meal was obtained from American Tung Oil Mills, Inc., Brooker, Florida, and was from freshly prepared tung press cake. Heat treatment was carried out by the U.S.D.A. Tung Oil Laboratory, Gainesville. The treatment consisted of adjusting the moisture of tung meal to IS.5 percent and of heating in an autoclave at 1 1 | pounds pressure, 115.5°C., for 90 minutes. After drying, a portion of the heat treated tung meal was passed through a 40 mesh screen. The portion which had the coarser particles of shell removed in this manner (38.3%) was the heat treated sifted tung meal included in the rations of lots 4 and 5. Raw tung meal was included in the experiment to provide a check on the effectiveness of the heat treatment, and to provide specimens of typical tung meal poisoning. An analysis of the tung meals used is given in Table 1. Eight lots of 25 S. C. White Leghorn chicks each were placed on experiment in individual wire mesh bottom brooders at two days of age. The composition of the basal ration is shown in Table 2, and that of the experimental rations is shown in 74
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
T
75
TUNG MEAL IN RATIONS FOR GROWING CHICKS TABLE 1.—Analysis of tung meals used
Tung meal
Treatment
Moisture
Protein (Nitrogen X6.25)
Ether extract
Crude fiber
Ash
Raw Press Cake Heated Press Cake Heated & Sieved Press Cake Heated Press Cake
1 2 3 4
6.2 9.9 9.8 9.6
22.71 21.56 32.28 23.38
1.27 1.25 1.47 1.21
33.81 30.74 11.93 30.55
5.59 5.26 7.42 5.30
N. F. E. 30.42 31.29 37.10 29.96
Treatment 1. Not processed. 2. Heated in an autoclave, 1J hours at 115.5° C. (240° F.) and 11.5 lbs. per sq. in. pressure. 3. Heated (as No. 2) and sieved on 40 mesh sieve. The 38.3 percent passing the 40 mesh sieve was used as Feed No. 3. 4. Heated in autoclave 1J hours at 128° C. (262.4° F.) and 22 lbs. per sq. in. pressure. TABLE 2.—Basal ration Pounds 360 70 30 50 30 30 60 30 20 10 10 57 gms. 90 gms.
Yellow corn meal Ground wheat Bran (wheat) Ground oats Meat scrap Whey Alfalfa leaf meal Produlac Bone meal Shell (oyster) Salt (NaCl) Manganese sulphate (MnSCu) Delsterol
TABLE 3.—Experimental rations and average weight of chicks in grams
Lot
Level of tung meal* Percent
Basal ration Percent
S.B.O.M4 Percent
Initial weight
1 2 3 4 5 6 7 8
0 5 10 5 10 5 10 15
70.0 68.3 66.6 69.0 68.0 67.8 65.6 63.4
30.0 26.7 23.4 26.0 22.0 27.2 24.4 21.6
35.6 36.6 35.5 36.8 33.4 37.1 33.4 36.4
Lot 1 9
0 15 -
70.0 63.4
30.0 21.6
Final weight adj. for sex infiu.
Feed utilization gms. feed/gm. gain
365.0 273.3 248.3 232.7
1.91 2.72 3.60 3.41
281.3
t t
2.73
3 wks. weight
10 wks. weight
Utilization 3 to 10 wks. gms. feed/gm.
164.5 101.8
863.4 532.3
Final weight 5 wks. 365.7 280.2 240.1 213.8 155.5 281.3 193.4
t
t t
'
3.65 5.85
* Lots 2 and 3 received unsifted heat treated tung meal, lots 4 and 5 received sifted heat treated tung meal, lots 6, 7 and 8 received raw tung meal and lot 9 received unsifted tung meal heated at 22 pound steam pressure. t Weights for lots 5 and 7 were not adjusted and feed utilization was not calculated because of high mortality. All chicks in lot 8 were dead at 4 weeks. | Soybean oil meal.
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
Table 3. The ration fed lot 1 is the same as that fed to the growing chicks of the University flock and is known to give good results. Lots 2, 4, and 6 received 5 percent and lots 3, 5, and 7 received 10 percent of the heat treated, heat treated sifted, and raw tung meals respectively. Lot number 8 received 15 percent raw tung meal. The quantity of soybean oil meal was adjusted to provide rations containing as nearly as possible 20 percent protein.
76
GEORGE K. DAVIS, N. R. MEHRHOF AND R. S. MCKINNEY TABLE 4.—Mortality of chicks by weeks Number of Chicks Dead
Lot 1 2 3 4 5 6 7 8 9
Week 1 2 3 4 5 Total 6 7 8 9 10 Total 0 0 2 0 3 1 1 3
0 0 0 0 0 0 0 0 1 0 0 0 1 1 2 2 2 12 9 2 0 0 2 4 4 5 8 3 23 0 0 0 0 1 S 7 0 4 17 11 8 3 25 1 1 2 3 2*
1
9
* Moribund.
RESULTS
The immediate reaction to the,feeding of all the tung meal rations was a severe diarrhea in the chicks receiving these rations. The droppings were very wet and foul smelling. The chicks soon became very dirty and feathers, as they developed, possessed an unnatural waxy feel. The diarrhea soon resulted in caking of
Beak and legs discolored, blue; vent dry and clean, but blue; crop nearly empty; severe ascites; subcutaneous tissues jaundiced; large areas of necrosis apparent on surface of liver; adhesions on liver indicative of inflammation; intestines full, lungs normal, gizzard full of feed about 50 percent tung shell. Other tissues and organs normal. Figures 1 and 2 show liver damage. In the chicks from lots receiving the raw tung meal and unsifted heat treated tung meal a frequent finding was a gizzard and intestinal tract with practically no other feed than tung shell. Presumably the chicks had picked out the dark pieces of shell preferentially. However, no inflammation of the gastro-intestinal tract was discovered in any of the chicks. During the first 3 weeks that lot 9 was on the experimental ration, the chicks grew at a rate comparable to that of the lots receiving 5 percent tung meal. However, there developed a waxy feel to their
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
Feed and water were kept before the chicks at all times and feed consumption measured weekly. All chicks were weighed at one week intervals. The mortality which developed early in the experiment on the heat treated tung meal caused a reevaluation to be made of the treatment and a second batch of tung meal was autoclaved at a temperature of 128°C. and 22 pounds pressure. There had been 23 chicks kept on the basal ration alone for such a contingency and at the beginning of the fourth week of the experiment lot 9 was started on a ration comparable to that given lot 8, but containing 15 percent of the special heat treated tung meal. This tung meal heated at the higher temperature and pressure for If hours had a dark brown, partially scorched appearance. Post mortem examinations were made on all chicks which died during the experiment and on several killed at the end of the experiment for comparative observation.
many of the vents and the first chicks to die showed apparent obstruction of the lower large intestine. Mortality records by weeks are shown in Table 4. It will be noted that the heaviest mortality was in the lots receiving the higher percentages of tung meal. After the first week the characteristic postmortem picture was one of liver damage and related pathology. Before death the legs and beak became bluish in color, indicative of cyanosis. In later instances, the skin over the abdomen frequently took on a bluish cast. Jaundice and ascites were usual findings after the second week on experiment. The gall bladder became greatly enlarged approaching the liver in size. Adhesions on the surface of the liver, indicating inflammation, were frequent and areas of massive necrosis within the liver were usual. A typical autopsy observation follows: (G-1551).
T U N G M E A L IN R A T I O N S FOR G R O W I N G C H I C K S
feathers and during the 3rd week on this ration and 6th of the experiment, mortality began to develop and by the 10th week of the experiment 7 of the 23 chicks were dead and 2 others moribund. On autopsy these chicks gave typical evidence of tung meal poisoning with gall bladder enlargement and characteristic damages to the body tissues associated with liver malfunction.
parent. At the 5 percent levels of tung meal, 2.72, 3.41 and 2.73 grams of feed were required to produce a gram of gain as compared to 1.91 grams of feed for lot 1 which received no tung meal. The inter-
FIG. 1. Liver from chick G1583 receiving IS percent raw tung meal. Note enlarged gall bladder and degenerated surface area.
ference with feed utilization is also evident in the results obtained with lot 9 as compared with lot 1. Although these chicks
FIG. 2. Livers from chick G1503 (left) on 10 percent heat treated and sieved tung meal and chick G1423 (right) on control ration. Note: These livers are in same relative position. While only the tip of the gall bladder shows below the liver of the control (just above the little finger), the gall bladder of the other chick is nearly one-half the size of the liver itself (just above the middle finger).
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
None of the tung meal lots gained as well as the control lot (#1). I n Table 3 the average weights at the beginning and a t the end of five weeks are shown for lots 1, 2, 3, 4, 5, 6 and 7. I n order to give a better comparison of lots 2, 4 and 6 receiving the 5 percent levels of tung meal the average weights were adjusted to take into account the fact t h a t lot 4 had a disproportionately large number of pullets. Table 3 also shows t h a t tung meal interfered with the utilization of the feed at the levels where toxicity was not so ap-
77
78
GEORGE K. DAVIS, N. R. MEHRHOF AND R. S. MCKINNEY
were thrifty and vigorous at three weeks of age they were considerably lighter in weight than the controls because of the low protein basal ration. The records show that lot 9 required 5.85 grams of feed compared to 3.65 grams for lot 1 to produce a gram of gain in the period from three to ten weeks of age. DISCUSSION
SUMMARY
1. Eight lots of 2 day old chicks were fed 0, 5, 10, and 15 percent levels of tung meal and one additional lot of 3 weeks old chicks was fed a 15 per cent level of tung meal to investigate its possible use as a source of protein in poultry rations. 2. The tung meal proved toxic whether raw, heated, or heated and sifted and caused heavy mortality at 10 and 15 percent levels. 3. At 5 percent and higher levels the tung meals interfered with feed utilization. 4. Tung meal, raw or autoclaved at 115.5°C. and 11.5 pounds pressure or at
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
The results of this experiment have demonstrated the toxicity of raw tung meal for chicks as has been noted by others. The tung meal which had been heated at 11.5 pounds pressure and 115.5°C. in the autoclave appeared to be as toxic as the raw tung meal. The relative toxicity of the heated tung meal which had been passed through a 40 mesh sieve was greater than either the raw or the heated unsifted tung meal. This finding would seem to indicate that the toxic principle of tung meal was more concentrated in the kernel. The tung shell did not cause obvious injury to the intestinal tract of the chicks, but the tendency of the chicks to pick out the shell to the exclusion of the other feed was an objectionable feature. At the 15 percent level of the raw tung meal the chicks were all dead at the end of four weeks except one which was killed in a moribund condition. At 5 weeks two chicks were left in lot 5 receiving the 10 percent sifted tung meal. One of these was moribund and extremely jaundiced. Those lots receiving 5 percent of the different tung meals did not suffer excessive mortality but the deleterious effect of its inclusion in the ration was evidenced by the lower rate of gain and by the poorer utilization of feed. All of these chicks had a waxy feel to the feathers which may have been indicative of some toxic reaction. From these results, it would appear
that the heat treatment used did not destroy the toxic principle of the tung meal. Furthermore the presence of tung meal in the rations at a level of 5 percent interfered with the utilization of the feed even though excess mortality was not encountered. Considering that the chicks in lot 9 were placed on the special heat treated tung meal at the age of 3 weeks, and therefore passed the period in which a heavy mortality occurred in some of the lots receiving this material and were presumably better able to resist toxic effects of the feed, it seems reasonable to assume that the tung meal, even though treated at the higher temperature, was relatively as toxic as the tung meal treated at the lower temperature. On the basis of results obtained in this experiment, it is apparent that heat treatment with a temperature as high as 262°F. and 22 pounds pressure is not sufficient to inactivate the toxic principle in tung meal. Because the higher temperature used caused a scorched product, it would seem very doubtful that tung meal can be rendered safe and suitable as a feed by heat treatment alone.
TUNG MEAL IN RATIONS FOR GROWING CHICKS
128°C. and 22 pounds pressure is not safe for use in chick feeds. BIBLIOGRAPHY
Anderson, E. M., 1942. Unpublished Work Poultry Laboratories, Animal Industry Dept. Univ. of Florida. Davis, H. J., 1940. Unpublished work. An. Industry Department, La. State University. Godden, W., 1933. The feeding value of tung-seed meal. Reprint. Bui. Imperial Institute 30: No. 3. Lewkowitsch, J. I., 1909. Chemical technology and
79
analysis of oils, fats and waxes. 4th edition McMillan and Company, London 2: p. 60. Newell, W., 1924. Preliminary report on experiments with the tung^oil tree in Florida. Florida Agr. Exp. Sta. Bui. 171. Sanders, D. A., M. W. Emmel and W. W. Henley, 1933. Unpublished work. An. Ind. Dept., Florida Agr. Exp. Station. Rusoff, L. L., N. R. Mehrhof and R. S. McKinney, 1942. Chick feeding experiments with solventextracted tung oil meal. Poultry Science 21:451454.
Downloaded from http://ps.oxfordjournals.org/ by guest on May 6, 2015
"J*