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Multiplex Combs
Multiplex Combs LEWIS W.
TAYLOR
University of California, Berkeley, Calif. (Received for publication June 12, 1946)
A
to two rose-combed (heterozygous) Hamburg females used in the production of the original crossbred stock. From all the rose-combed dams, 23 rosecombed and 21 non-rose offspring were obtained. Of the rose combs, 14 showed defective bifid or trifid spikes instead of a single normal spike. From this, it would appear that the multiplex condition may be expressed weakly in a rose comb and more effectively in non-rose combs. Of the non-rose offspring from the mating of this male to his dam, 2 possessed sidesprigged single or duplex and 3 had duplex-triplex types of comb. The Hamburg dams produced 3 single, 6 sidesprigged single or duplex, 5 singletriplex, 14 duplex-triplex and 1 duplexquadruplex as non-rose types of combs. The triplex X triplex matings gave 1 single, 6 sidesprigged single or duplex, 8 singletriplex, 6 duplex-triplex and no rose combs. I t is apparent that the triplexcombed sire was genetically non-rose and gave the same proportion of non-rose offspring in matings with heterozygous rosecombed females as would be expected in single X heterozygous rose matings. PRODUCTION OF PURE-BREEDING MULTIPLEX STOCK Since 1941, matings have been designed each year to attempt to fix and intensify the more complicated multiplex comb types. In 1941 the first individual with duplex-quadruplex comb was produced; in 1944 and 1945 a few duplexquintuplex individuals, mostly males, were obtained. Since 1941 no rose-combed
610
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SERIES of peculiar comb types was observed in the offspring of a crossbred male L160 [Columbian Rock c? XFi 9 (Columbian Rock cfX Hamburg $)] produced in 1940. This male was mated to three females from Fief (Hamburg cfX Columbian Rock 9)XHamburg 9 9 matings, one F 2 9 (Hamburg c? X Columbian Rock 9 ) and one female from a Fid 1 (Hamburg cfXColumbian Rock 9 ) X Columbian Rock 9 mating. Male L160 possessed a true single comb without defects, but he was derived from a mating which produced two sidesprigged individuals in ten single-combed sibs. Of the females mated to L160, four were rosecombed (heterozygous) and one had a sidesprigged single comb. The unusual comb types in the offspring ranged from sidesprigged single combs, through duplex types resembling in best developed forms a small, poorly shaped Buttercup comb, to a triplex type which might easily have been mistaken for a pea comb on casual inspection. These unusual forms and more complex types produced later are termed multiplex combs. For greater accuracy in description individual multiplex combs are hereafter given hyphenated names in sequence of conditions of portions of the comb from front to rear, i.e. single-triplex = single anteriorly, triplex (three rows of serrations) posteriorly (see comb types illustrated in Figure 1). In 1941 a triplex-combed male was mated to: 1) his heterozygous rosecombed dam, 2) to one full-sister and two half-sisters, all with triplex combs, and 3)
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FIG. 1. Types of multiplex combs: 9T1669, duplex; 9T1673, single-triplex; 9T166S, duplex-triplex; D126 o" weakly developed single-triplex; D144 c? and V170 d1, duplex-quadruplex.
612
LEWIS W. TAYLOR
stock has been used in matings and no rose combs have been obtained in the offspring. This is further clear evidence that the multiplex combs are not modified rose combs. Table 1 gives the percentage of the various types of combs obtained from 1940 through 1945. In 1940 and 1941 data, the percentage of each type is
that its origin was associated with modified single combs. RECIPROCAL MULTIPLEXXSINGLE MATINGS
In 1944 the multiplex stock, which produced a generation of multiplex combs with no expression simpler than the triplex type, was mated to Single Comb
TABLE 1.—Frequency of multiplex comb types in offspring produced during six years of selection Comb Types—classified with regard to greatest complexity
1940* fall matings) 1940* (only matings producing multiplex) 1941* 1942 1943 1944 1945
Number of birds
Single
30 21
46.7 23.8
23.3 33.3
50 39 52 40 66
8.0 10.3 0.0 0.0 0.0
24.0 28.2 1.9 0.0 0.0
%
Sidesprigged Single or Duplex
Triplex
%
'
Quadruplex Quintuplex
%
%
66.0 48.7 42.3 32.5 22.7
2.0 12.8 55.8 60.0 74.3
30.0 42.9
0.0 0.0
%
0.0 0.0 0.0 0.0 0.0 7.5 3.0 •
* Based on total of non-rose offspring only.
based on the total of non-rose offspring only. The comb types in Table 1 are generally determined by the complexity of the posterior portion of the comb. Combs with one or more unilateral sidesprigs are combined with duplex combs possessing two definite ridges of serrations, since the two conditions possess confusing intergrading stages; similarly, bilateral sidesprigs intergrade through stages involving increase in number of serrations into a typical triplex structure and are therefore classed as triplex combs. From the results given in Table 1, it is clear that selection has been effective in the production of the more complex types of combs and in the elimination of single, sidesprigged single and duplex types. The 1943 matings were the last in which the multiplex stock gave any visible indication
White Leghorns from families in which no tendency for sidesprigging had been noted for several generations. Results of the matings are given in Table 2. The data indicate that multiple factors are involved in the production of the more complex types of multiplex combs. With the exception of two quadruplex individuals sired by the duplex-triplex male, all Fi individuals possessed combs of no greater complexity than their multiplex parent. The appearance of large numbers of single and sidesprigged single combs in the Fi proves that the multiplex stock was still not homozygous for all of the factors in which it differs from stocks with normal or sidesprigged single combs. BACKCROSS TO SINGLE COMBED STOCK I n 1945, Fi 9 9 representing nearly all
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Year
MULTIPLEX
613
COMBS
TABLE 2.—Comb types in offspring from reciprocal multiplexXSingle
Comb White Leghorn malings
Mating
Single
Duplex-quadruplex cfcfX single 9 Single-quadruplex
Sidesprigged single or duplex
Singletriplex
Duplextriplex
III
Combs in Fi individuals Duplexquadruplex
6 4 8
1
2
1
1
5
6 10 8 4 7
2
—
—
26
29
35
20
2
3
22.6
25.2
3 18 2
9 5 10
3
Total Percentage
47.8
4.4
TABLE 3.—Results of backcrossing F\ 9 9 possessing various comb
phenotypes to a Single Comb White Leghorn male Percentage
Combs in offspring Fi Dam's phenotype Single
Sidesprigged single or duplex
Singletriplex
Single
Triplex
5 2
85.7 59.1 50.0 46.7 57.7 41.2 36.8
2.9 27.3 33.3 26.7 23.1 35.3 31.6
Duplextriplex
Single Sidesprigged or Duplex Single-duplex-single-triplex Duplex-single-triplex Single-triplex Duplex-triplex Duplex-quadruplex
30 13 6 7 15 14 7
4 3 2 4 5 8 6
1 4 3 1 6 7 4
From all backcrosses
92
32
26
13
56.4
23.9
From all multiplex dams
62
28
25
13
48.4
29.7
From triplex and quadruplex dams
49
25
21
11
46.2
30.2
2 1 3
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types. I t is clear that the Fi dams possessing true single combs are genetically distinct from other Fi 9 9 . That these single-combed dams carried some factors involved in the production of multiplex comb types is evidenced by their production of one triplex and four sidesprigged single or duplex combs. Amongst the remaining Fi dam's phenotypes there is only a slight and non-significant trend for the more complexly combed groups to give higher ratios of multiplex combs in the backcross off-
phenotypic variations of comb types in that generation were mated to a Single Comb White Leghorn d" chosen from a line which had no recent history of sidesprigging. The results of this backcross mating are given in Table 3. The dam's comb phenotype is described in detail in this table in order to indicate every change in comb structure in an antero-posterior sequence. Of the various comb phenotypes tested by backcrossing, that of single gave results different from the other six pheno-
614
LEWIS W. TAYLOR
DISCUSSION AND SUMMARY
Since the earliest forms of triplex combs obtained were associated with the production of sidesprigs in other members of the family, and since the Fi generation of multiplex X single and the backcross generation of single XFi again brought forth large numbers of sidesprigged individuals, it may be assumed that genes for sidesprigging play a part in the production of multiplex combs. Asmundson (1926) has shown that the complementary action of two genes is necessary to produce sidesprigs on single combs. There is also strong evidence of the complementary action of genes in the production of the multiplex comb types. It may well be that simple sidesprigs are the weak expression of certain genes, which by the supplementary action of other genetic modifying factors are able to produce the more complicated types of multiplex combs. While it has been possible to fix the production of multiplex combs in the selected stock to the point that no types simpler than the triplex condition are produced, very good evidence exists in the Fi generation of multiplex X single that
considerable heterozygosity for genes controlling the multiplex comb still exists in the selected lines and that the ultimate in complexity of the multiplex comb may not yet have been reached. All the evidence points to multiple factors as responsible for the production of multiplex combs. The possibility of considerable phenotypic variation in expression of combs produced by the same genotype finds support in data from the backcross generation. Alder (1941) reported in an abstract that selection in single-combed stock towards pea combs by mating sidesprigged birds resulted in more and larger sidesprigs, and eventually in combs " . . . with ridges on each side of the base of the single comb, each ridge with four to five points." This was interpreted as a change of single to pea comb by selection. The triplex types of combs here reported may easily be mistaken for pea combs. While the lateral ridges of the true pea comb are smaller and lower than the median ridge and the serrations on the lateral ridges fail to equal the height of the serrations of the middle ridge, all ridges of the triplex and more complicated types of multiplex comb tend to be on the same horizontal plane and the serrations of all ridges are of approximately equal height. The true pea comb also has been shown to be produced by a simple autosomal gene incompletely dominant to single comb and further that this gene interacts with the gene for rose comb to produce a walnut comb (Punnett, 1923). The mating of triplex c?X heterozygous rose comb 9 9 , however, produced no walnut-combed offspring. The triplex or other multiplex combs, therefore, are genetically distinct from pea combs. The fact that both Alder and the writer used substantially the same procedure in developing complex types of comb from sidesprigged single-combed stock may
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spring. It is indicated either that the phenotypic expression of identical genotypes of the multiplex condition is extremely variable or that the genetic basis for production of the multiplex comb is very complex. If the latter explanation is correct there is evidence in the backcross generation that the complementary action of some genes is involved in the production of more complex combs, such as triplex types, from dams with single, sidesprigged single or duplex combs. The possibility that the Single Comb White Leghorn sire may have contributed certain genes to such complementary action can not be excluded.
615
N E W S AND NOTES
cast doubt as to the accuracy of the interpretation that pea combs may be derived by selection from single-combed stock. In summary, it may be said that the development of a true-breeding strain of chickens having multiplex combs, fundamentally a modification of the single comb, has been demonstrated. The strain is not yet homozygous for all genes involved in the production of multiplex types of comb and considerable variation in complexity of phenotypic expression of the condition is still obtained. Multiple factors, some with complementary action
and apparently identical with genes producing sidesprigs, are involved in the production of multiplex combs. Although certain multiplex combs resemble pea combs, they are genetically distinct from the true pea comb. REFERENCES
Alder, H. E., 1941. Modification of comb characters in chickens. Poultry Sci. 20: 454. Asmundson, V. S., 1926. Inheritance of sidesprigs* Jour. Hered. 17: 280-284. Punnett, R. C , 1923. Heredity in Poultry. Macmillan & Co., London.
Dr. Jesse E. Parker, formerly chairman of the Department of Poultry Husbandry, North Dakota Agricultural College, is now Head of the Poultry Husbandry Department at Oregon State College, Corvallis. Dr. R. M. Conrad has joined the Bureau of Applied Science and Engineering Research, at the University of Denver. Dr. Conrad was previously Agricultural Chemist at Kansas State College. Dr. Reece L. Bryant, formerly of the Poultry Department, Virginia Polytechnic Institute, is now Chairman of the Poultry Husbandry Department, North Dakota Agricultural College. Dr. R. E. Phillips is now Professor in charge of the Department of Poultry Husbandry, Iowa State College. J. R. Cavers, formerly in charge of the Department of Poultry Husbandry, University of Manitoba, has resigned to accept a position of Professor of Poultry Husbandry, Ontario Agricultural College.
J. R. Couch is on leave of absence from the Texas Agricultural Experiment Station and is taking advanced studies at the University of Wisconsin on a grant from the General Education Board, New York. On July IS Dr. Dean G. Jones (B.S., Purdue 1939; M.S., 1941, Ph.D., Cornell, 1946) joined the staff of the South Dakota State College as Assistant Professor of Poultry Husbandry, and Assistant Poultry Husbandman in the Experiment Station. P. A. Kondra is now Assistant Professor of Poultry Husbandry at the University of Manitoba. After a leave of absence for 18 months serving as Field Supervisor for the Southern States Eastern Shore Marketing Cooperative, W. H. Rice has returned to the University of Maryland to his former duties as Extension Poultry Husbandman. J. K. Bletner, formerly Assistant Extension Poultryman at West Virginia Uni-
(Conlinued on page 648)
Downloaded from http://ps.oxfordjournals.org/ by guest on April 8, 2015
News and Notes
TAYLOR
University of California, Berkeley, Calif. (Received for publication June 12, 1946)
A
to two rose-combed (heterozygous) Hamburg females used in the production of the original crossbred stock. From all the rose-combed dams, 23 rosecombed and 21 non-rose offspring were obtained. Of the rose combs, 14 showed defective bifid or trifid spikes instead of a single normal spike. From this, it would appear that the multiplex condition may be expressed weakly in a rose comb and more effectively in non-rose combs. Of the non-rose offspring from the mating of this male to his dam, 2 possessed sidesprigged single or duplex and 3 had duplex-triplex types of comb. The Hamburg dams produced 3 single, 6 sidesprigged single or duplex, 5 singletriplex, 14 duplex-triplex and 1 duplexquadruplex as non-rose types of combs. The triplex X triplex matings gave 1 single, 6 sidesprigged single or duplex, 8 singletriplex, 6 duplex-triplex and no rose combs. I t is apparent that the triplexcombed sire was genetically non-rose and gave the same proportion of non-rose offspring in matings with heterozygous rosecombed females as would be expected in single X heterozygous rose matings. PRODUCTION OF PURE-BREEDING MULTIPLEX STOCK Since 1941, matings have been designed each year to attempt to fix and intensify the more complicated multiplex comb types. In 1941 the first individual with duplex-quadruplex comb was produced; in 1944 and 1945 a few duplexquintuplex individuals, mostly males, were obtained. Since 1941 no rose-combed
610
Downloaded from http://ps.oxfordjournals.org/ by guest on April 8, 2015
SERIES of peculiar comb types was observed in the offspring of a crossbred male L160 [Columbian Rock c? XFi 9 (Columbian Rock cfX Hamburg $)] produced in 1940. This male was mated to three females from Fief (Hamburg cfX Columbian Rock 9)XHamburg 9 9 matings, one F 2 9 (Hamburg c? X Columbian Rock 9 ) and one female from a Fid 1 (Hamburg cfXColumbian Rock 9 ) X Columbian Rock 9 mating. Male L160 possessed a true single comb without defects, but he was derived from a mating which produced two sidesprigged individuals in ten single-combed sibs. Of the females mated to L160, four were rosecombed (heterozygous) and one had a sidesprigged single comb. The unusual comb types in the offspring ranged from sidesprigged single combs, through duplex types resembling in best developed forms a small, poorly shaped Buttercup comb, to a triplex type which might easily have been mistaken for a pea comb on casual inspection. These unusual forms and more complex types produced later are termed multiplex combs. For greater accuracy in description individual multiplex combs are hereafter given hyphenated names in sequence of conditions of portions of the comb from front to rear, i.e. single-triplex = single anteriorly, triplex (three rows of serrations) posteriorly (see comb types illustrated in Figure 1). In 1941 a triplex-combed male was mated to: 1) his heterozygous rosecombed dam, 2) to one full-sister and two half-sisters, all with triplex combs, and 3)
Downloaded from http://ps.oxfordjournals.org/ by guest on April 8, 2015
FIG. 1. Types of multiplex combs: 9T1669, duplex; 9T1673, single-triplex; 9T166S, duplex-triplex; D126 o" weakly developed single-triplex; D144 c? and V170 d1, duplex-quadruplex.
612
LEWIS W. TAYLOR
stock has been used in matings and no rose combs have been obtained in the offspring. This is further clear evidence that the multiplex combs are not modified rose combs. Table 1 gives the percentage of the various types of combs obtained from 1940 through 1945. In 1940 and 1941 data, the percentage of each type is
that its origin was associated with modified single combs. RECIPROCAL MULTIPLEXXSINGLE MATINGS
In 1944 the multiplex stock, which produced a generation of multiplex combs with no expression simpler than the triplex type, was mated to Single Comb
TABLE 1.—Frequency of multiplex comb types in offspring produced during six years of selection Comb Types—classified with regard to greatest complexity
1940* fall matings) 1940* (only matings producing multiplex) 1941* 1942 1943 1944 1945
Number of birds
Single
30 21
46.7 23.8
23.3 33.3
50 39 52 40 66
8.0 10.3 0.0 0.0 0.0
24.0 28.2 1.9 0.0 0.0
%
Sidesprigged Single or Duplex
Triplex
%
'
Quadruplex Quintuplex
%
%
66.0 48.7 42.3 32.5 22.7
2.0 12.8 55.8 60.0 74.3
30.0 42.9
0.0 0.0
%
0.0 0.0 0.0 0.0 0.0 7.5 3.0 •
* Based on total of non-rose offspring only.
based on the total of non-rose offspring only. The comb types in Table 1 are generally determined by the complexity of the posterior portion of the comb. Combs with one or more unilateral sidesprigs are combined with duplex combs possessing two definite ridges of serrations, since the two conditions possess confusing intergrading stages; similarly, bilateral sidesprigs intergrade through stages involving increase in number of serrations into a typical triplex structure and are therefore classed as triplex combs. From the results given in Table 1, it is clear that selection has been effective in the production of the more complex types of combs and in the elimination of single, sidesprigged single and duplex types. The 1943 matings were the last in which the multiplex stock gave any visible indication
White Leghorns from families in which no tendency for sidesprigging had been noted for several generations. Results of the matings are given in Table 2. The data indicate that multiple factors are involved in the production of the more complex types of multiplex combs. With the exception of two quadruplex individuals sired by the duplex-triplex male, all Fi individuals possessed combs of no greater complexity than their multiplex parent. The appearance of large numbers of single and sidesprigged single combs in the Fi proves that the multiplex stock was still not homozygous for all of the factors in which it differs from stocks with normal or sidesprigged single combs. BACKCROSS TO SINGLE COMBED STOCK I n 1945, Fi 9 9 representing nearly all
Downloaded from http://ps.oxfordjournals.org/ by guest on April 8, 2015
Year
MULTIPLEX
613
COMBS
TABLE 2.—Comb types in offspring from reciprocal multiplexXSingle
Comb White Leghorn malings
Mating
Single
Duplex-quadruplex cfcfX single 9 Single-quadruplex
Sidesprigged single or duplex
Singletriplex
Duplextriplex
III
Combs in Fi individuals Duplexquadruplex
6 4 8
1
2
1
1
5
6 10 8 4 7
2
—
—
26
29
35
20
2
3
22.6
25.2
3 18 2
9 5 10
3
Total Percentage
47.8
4.4
TABLE 3.—Results of backcrossing F\ 9 9 possessing various comb
phenotypes to a Single Comb White Leghorn male Percentage
Combs in offspring Fi Dam's phenotype Single
Sidesprigged single or duplex
Singletriplex
Single
Triplex
5 2
85.7 59.1 50.0 46.7 57.7 41.2 36.8
2.9 27.3 33.3 26.7 23.1 35.3 31.6
Duplextriplex
Single Sidesprigged or Duplex Single-duplex-single-triplex Duplex-single-triplex Single-triplex Duplex-triplex Duplex-quadruplex
30 13 6 7 15 14 7
4 3 2 4 5 8 6
1 4 3 1 6 7 4
From all backcrosses
92
32
26
13
56.4
23.9
From all multiplex dams
62
28
25
13
48.4
29.7
From triplex and quadruplex dams
49
25
21
11
46.2
30.2
2 1 3
Downloaded from http://ps.oxfordjournals.org/ by guest on April 8, 2015
types. I t is clear that the Fi dams possessing true single combs are genetically distinct from other Fi 9 9 . That these single-combed dams carried some factors involved in the production of multiplex comb types is evidenced by their production of one triplex and four sidesprigged single or duplex combs. Amongst the remaining Fi dam's phenotypes there is only a slight and non-significant trend for the more complexly combed groups to give higher ratios of multiplex combs in the backcross off-
phenotypic variations of comb types in that generation were mated to a Single Comb White Leghorn d" chosen from a line which had no recent history of sidesprigging. The results of this backcross mating are given in Table 3. The dam's comb phenotype is described in detail in this table in order to indicate every change in comb structure in an antero-posterior sequence. Of the various comb phenotypes tested by backcrossing, that of single gave results different from the other six pheno-
614
LEWIS W. TAYLOR
DISCUSSION AND SUMMARY
Since the earliest forms of triplex combs obtained were associated with the production of sidesprigs in other members of the family, and since the Fi generation of multiplex X single and the backcross generation of single XFi again brought forth large numbers of sidesprigged individuals, it may be assumed that genes for sidesprigging play a part in the production of multiplex combs. Asmundson (1926) has shown that the complementary action of two genes is necessary to produce sidesprigs on single combs. There is also strong evidence of the complementary action of genes in the production of the multiplex comb types. It may well be that simple sidesprigs are the weak expression of certain genes, which by the supplementary action of other genetic modifying factors are able to produce the more complicated types of multiplex combs. While it has been possible to fix the production of multiplex combs in the selected stock to the point that no types simpler than the triplex condition are produced, very good evidence exists in the Fi generation of multiplex X single that
considerable heterozygosity for genes controlling the multiplex comb still exists in the selected lines and that the ultimate in complexity of the multiplex comb may not yet have been reached. All the evidence points to multiple factors as responsible for the production of multiplex combs. The possibility of considerable phenotypic variation in expression of combs produced by the same genotype finds support in data from the backcross generation. Alder (1941) reported in an abstract that selection in single-combed stock towards pea combs by mating sidesprigged birds resulted in more and larger sidesprigs, and eventually in combs " . . . with ridges on each side of the base of the single comb, each ridge with four to five points." This was interpreted as a change of single to pea comb by selection. The triplex types of combs here reported may easily be mistaken for pea combs. While the lateral ridges of the true pea comb are smaller and lower than the median ridge and the serrations on the lateral ridges fail to equal the height of the serrations of the middle ridge, all ridges of the triplex and more complicated types of multiplex comb tend to be on the same horizontal plane and the serrations of all ridges are of approximately equal height. The true pea comb also has been shown to be produced by a simple autosomal gene incompletely dominant to single comb and further that this gene interacts with the gene for rose comb to produce a walnut comb (Punnett, 1923). The mating of triplex c?X heterozygous rose comb 9 9 , however, produced no walnut-combed offspring. The triplex or other multiplex combs, therefore, are genetically distinct from pea combs. The fact that both Alder and the writer used substantially the same procedure in developing complex types of comb from sidesprigged single-combed stock may
Downloaded from http://ps.oxfordjournals.org/ by guest on April 8, 2015
spring. It is indicated either that the phenotypic expression of identical genotypes of the multiplex condition is extremely variable or that the genetic basis for production of the multiplex comb is very complex. If the latter explanation is correct there is evidence in the backcross generation that the complementary action of some genes is involved in the production of more complex combs, such as triplex types, from dams with single, sidesprigged single or duplex combs. The possibility that the Single Comb White Leghorn sire may have contributed certain genes to such complementary action can not be excluded.
615
N E W S AND NOTES
cast doubt as to the accuracy of the interpretation that pea combs may be derived by selection from single-combed stock. In summary, it may be said that the development of a true-breeding strain of chickens having multiplex combs, fundamentally a modification of the single comb, has been demonstrated. The strain is not yet homozygous for all genes involved in the production of multiplex types of comb and considerable variation in complexity of phenotypic expression of the condition is still obtained. Multiple factors, some with complementary action
and apparently identical with genes producing sidesprigs, are involved in the production of multiplex combs. Although certain multiplex combs resemble pea combs, they are genetically distinct from the true pea comb. REFERENCES
Alder, H. E., 1941. Modification of comb characters in chickens. Poultry Sci. 20: 454. Asmundson, V. S., 1926. Inheritance of sidesprigs* Jour. Hered. 17: 280-284. Punnett, R. C , 1923. Heredity in Poultry. Macmillan & Co., London.
Dr. Jesse E. Parker, formerly chairman of the Department of Poultry Husbandry, North Dakota Agricultural College, is now Head of the Poultry Husbandry Department at Oregon State College, Corvallis. Dr. R. M. Conrad has joined the Bureau of Applied Science and Engineering Research, at the University of Denver. Dr. Conrad was previously Agricultural Chemist at Kansas State College. Dr. Reece L. Bryant, formerly of the Poultry Department, Virginia Polytechnic Institute, is now Chairman of the Poultry Husbandry Department, North Dakota Agricultural College. Dr. R. E. Phillips is now Professor in charge of the Department of Poultry Husbandry, Iowa State College. J. R. Cavers, formerly in charge of the Department of Poultry Husbandry, University of Manitoba, has resigned to accept a position of Professor of Poultry Husbandry, Ontario Agricultural College.
J. R. Couch is on leave of absence from the Texas Agricultural Experiment Station and is taking advanced studies at the University of Wisconsin on a grant from the General Education Board, New York. On July IS Dr. Dean G. Jones (B.S., Purdue 1939; M.S., 1941, Ph.D., Cornell, 1946) joined the staff of the South Dakota State College as Assistant Professor of Poultry Husbandry, and Assistant Poultry Husbandman in the Experiment Station. P. A. Kondra is now Assistant Professor of Poultry Husbandry at the University of Manitoba. After a leave of absence for 18 months serving as Field Supervisor for the Southern States Eastern Shore Marketing Cooperative, W. H. Rice has returned to the University of Maryland to his former duties as Extension Poultry Husbandman. J. K. Bletner, formerly Assistant Extension Poultryman at West Virginia Uni-
(Conlinued on page 648)
Downloaded from http://ps.oxfordjournals.org/ by guest on April 8, 2015
News and Notes