Divergent Selection for Growth in Japanese Quail Under Split and Complete Nutritional Environments

Divergent Selection for Growth in Japanese Quail Under Split and Complete Nutritional Environments. 3. Influences of Selection for Growth on Heterotic Effects for Body Weight, Feed and Water Intake Patterns, Abdominal Fat, and Carcass Lipid Characteristics J. R. DARDEN1 Department of Poultry Science, University of Georgia Athens, Georgia 30602

USDA, Agricultural Research Service, Southeast Poultry Research Laboratory, University of Georgia, 107 Livestock-Poultry Building, Athens, Georgia 30602 (Received for publication January 19, 1988) ABSTRACT A study was conducted to investigate heterotic effects for body weight, water and feed intake, abdominal fat and carcass lipid levels, and feed efficiency in progeny produced from reciprocal crosses of high (H) and low (L) body weight lines of Japanese quail selected under split diet (SD) and complete diet (CD) environments. Birds under the SD environment could self select feed from high protein and high energy diets. Crossline progeny from the selected lines were evaluated within the respective SD and CD environments in Generation 13. Small egg size of the L dam resulted in a negative maternal effect on the body weight of the HL crossline progeny and the large egg size of the H dam produced a positive maternal influence on the weight of LH crossline progeny. Heterotic effects for water and feed consumption corresponded with the trends for heterosis in body weight. Heterotic effects for abdominal fat and carcass lipid levels were highly negative, and corresponded with trends for heterosis in feed efficiency. (Key words: heterosis, feed intake, feed efficiency, growth, body weight) 1989 Poultry Science 6 8 : 3 7 - 4 5 INTRODUCTION

Heterosis in domesticated and laboratory animals, insects, and plant species has been extensively reviewed (Hayes et al., 1955; Wright, 1977; Sheridan, 1981; Cunningham, 1982); it has been defined as the superiority of the performance of crossbred offspring over the average performance of the two parental lines. It is best exemplified in traits with low to average heritability, and is generally assumed to be the result of nonadditive (dominant, overdominant, and epistatic) gene action (Bell, 1982). Heterosis is known to be a result of the interaction between genetic and environmental stimuli (Lewis, 1954; McWilliam and Griffing, 1965;

r

Pr7s^taddress:ShowellFarms,Showeil,MD2l862. To whom correspondence should be addressed.

2

Pederson, 1968). Griffing and Zsiros (1971) indicated that if plant hybrids were to be used to their maximum potential, their nutritional status must be optimized. Progeny of crosses between lines of Japanese quail selected under adequate and inadequate nutritional environments were tested in four different (superior and inferior) nutritional environments and were found to exhibit minor positive (4 to 9%) heterosis for 4-wk BW in all environments; however, the greatest heterosis was exhibited in the stress or inadequate environments (Marks, 1973). Greater heterosis in stressful than nonstressful environments was also exhibited by cattle crosses in work by Barlow (1981). The relationship between heterosis for growth, water and feed intake and carcass characteristics in poultry is not clear. When given ad libitum feed and water, progeny from

37

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H. L. MARKS2

38

DARDEN AND MARKS MATERIALS AND METHODS

Four matings, two pureline (HH, LL) and two reciprocal crosses (HL and LH) were arranged in both the split diet (SD) and complete diet (CD) environments to produce the progeny for testing (Table 1). Progeny were produced by breeders that had undergone divergent selection for 4-wk BW under SD and CD environments for 12 generations (Darden and Marks, 1988a). A total of 240 chicks per environment was banded, weighed, and divided by cross into four replicates (15 quail/replicate per cross per environment) at day of hatch. Chicks were then placed in five-deck quail battery brooders with sexes combined and maintained in their respective environments through 4 wk of age. Chicks were identified at day of hatch with legbands, which were replaced by wingbands at 2 wk of age. The BW were obtained at weekly intervals. Water intake (corrected for evaporative loss), TFC, PDC, EDC (g consumed/bird), FE, and ratios of W:TFC, W:PDC, W:EDC, and EDQPDC and RGR data were obtained through 4 wk of age. Watentotal feed consumed ratio data per week were calculated by dividing mean W consumption by mean TFC for each pen/ cross/environment. Other ratio data were calculated by similar methods. Relative growth rate data were calculated as BW gain per week divided by final BW of the previous week, i.e., [(BW2 - BW1)/BW1] x 100. Abdominal fat (including gizzard fat) was removed from 10 quail/sex/cross/environment at 4 wk of age and then weighed. Fat was placed back into the carcasses, and carcasses were then stored frozen for later fat analysis. Carcasses were ground and thoroughly homogenized (feathers included), and percentage carcass lipid was determined by the method of Washburn and

TABLE 1. Matings to produce cross and pureline offspring within the split and complete diet selection environments Parent;i No. pairs

Male

Female

Progeny code

15 15 15 15

H-line H-line L-line L-line

H-line L-line H-line L-line

HH HL LH LL

1

H = High BW; L = low BW.

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a cross between a high and a low line of chickens that had undergone 22 generations of divergent selection for 8-wk BW exhibited negative heterosis for BW through 2 wk of age, accompanied by strong positive heterosis for feed efficiency to 4 wk of age, strong negative heterosis for 4-wk abdominal fat pad weight and minor negative heterosis for 4-wk breast weight (Barbato et al., 1983). Wyatt et at. (1982) found that minor negative heterosis for BW and breast weight and percentage breast weight were accompanied by strong negative heterotic effects for weight, size and number of adipocytes in the abdominal fat depots, weight of the sartorial fat depot, and percentage of fat in progeny from crosses of Japanese quail lines that had undergone 20 generations of divergent selection for mating frequency. These authors hypothesized that heterosis in feed efficiency is reflected by negative heterosis for fat deposition which explains why hybrids utilize their feed more efficiently than birds from the parental lines. Darden and Marks (1988a) developed high (H) and low (L) lines of Japanese quail divergently selected for 4-wk BW under split (inadequate) and complete (adequate) nutritional environments. These high and low lines were evaluated in their selection and foreign environments and were found to be different in BW, relative growth rate, water, feed protein diet and energy diet consumption, feed efficiency, and abdominal fat and carcass lipid levels (Darden and Marks, 1988b). The first objective of this study was to simultaneously test reciprocal cross and pureline chicks from the H and L quail lines developed by Darden and Marks (1988a) under their respective selection diet environments. Traits measured included BW, relative growth rate (RGR), water consumption (W), total feed consumption (TFC), protein diet consumption (PDC), energy diet consumption (EDC), feed efficiency (FE), abdominal fat weight (AF), and carcass lipid levels (CLL). Heterotic effects were determined for these parameters. The second objective was to observe pureline performance of the H and L lines, which had been selected under the SD and CD environments, when tested under their home environments in order to assess whether or not the selection for 4-wk BW under the two environments had resulted in differences in performance of the sublines. The same set of parameters mentioned in objective one were measured.

HETEROSIS IN GROWTH-SELECTED QUAIL

Yijk = (t + L; + Sj + LS y + eijk

[1]

where |j, is the common mean; L; is the effect of the ith line; Sj is the effect of the j t h sex; LSy is the interaction of the ith line with the j " 1 sex; ejjk is random error. As the sex effect was observed not to be significant (P<.05) in any of these analyses, data for these traits (BW, AF, and CLL) as well as data for W, TFC, PDC, EDC, FE, W:TFC, W:PDC, W:EDC, EDC:PDC, and RGR were analyzed within environment and week with the following model: Yy = U | L + Li + ey

[2]

where |x is the common mean; L; is the effect of the ith line; ey is random error. Orthogonal linear contrast was used to compare progeny from the various mating combinations. Contrasts showing the sire first and the dam line second were: 1) (HH + LL)-(HL + LH), 2) HHLL, and 3) HL-LH. Contrast 1 evaluates differences between purelines and crosslines (heterosis), Contrast 2 measures the differences between the divergently selected high and low lines, and Contrast 3 measures reciprocal effects between crosses HL and LH (maternal and sexlinked effects). RESULTS AND DISCUSSION

BW and Relative Growth Rate. Quail from HH lines were significantly (P<.0001) larger in BW than quail from LL lines within both SD and CD environments (Table 2). These differences in BW between lines within environment were consistent with those of earlier generations

reported by Darden and Marks (1988a,b). At day of hatch, HL quail were similar in BW to LL quail and LH quail were similar in BW to HH quail within both SD and CD environments. As eggs laid by LL breeders were significantly smaller than eggs laid by HH breeders (Darden and Marks, 1988a), egg size apparently influenced chick weight at day of hatch as has been shown with numerous studies with chickens. Significant (P<.01) positive heterosis (8%) for BW at day of hatch was found for LH and HL quail within the SD environment, whereas there was an apparent lack of heterosis at this age in the CD environment (Table 3). There was also no evidence of heterosis for 1-wk-old BW in either the SD or CD environments (Table 3). The LH quail were significantly larger than HL quail from 1 to 4 wk of age within both SD and CD environments (Table 2). The apparent maternal influence of egg size on BW was prevalent through 4 wk of age for HL quail. Significant (P<.01) negative heterosis of 6.7 to 11.1 % for B W of 2 to 4-wk-old quail was found in the crosses (Table 3). Barbato et al. (1983) found a maternal influence on body weight through 2 wk of age in cross (HL) progeny from chicken lines that had undergone 22 generations of divergent selection for 8-wk-old BW. In reciprocal crosses between inbred lines of White Leghorns, there was evidence for both maternal and sex-linked effects on adult size, with maternal and sex-linked effects exerting their influences on size and conformation, respectively (Cock and Morton, 1963). Maternal effects from the influence of egg weight on BW were also suggested by Proudfoot and Hulan (1981) and Washburn (1983). Important sex-linked effects were reported by Bernon and Chambers (1985). Sefton and Siegel (1974) and Wyatt et al. (1982) found no evidence of a maternal influence on BW by 8 wk of age in Japanese quail hybrid progeny. Quail from HH lines had significantly (P< .004) higher RGR (data not shown) through 2 wk of age than quail from LL-lines within both the SD and CD environments. Darden and Marks (1988b) reported similar within-environment differences between HH and LL lines for RGR in Generations 6 and 10. The HL and LH quail within environments were intermediate in RGR through 2 wk of age to the parent lines; however, there was no evidence of heterosis for RGR in either environment. The maternal effect of egg size on BW was not demonstrated in RGR data.

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Nix (1974), which was a modification of the method of Folch et al. (1957). Percentage AF was obtained by dividing the AF weight by live 4-wk BW. Carcass lipid level was expressed as grams of lipid liberated per gram homogenized carcass. Heterosis for traits within each environment was expressed as the percentage deviation of HL and LH line averages from the midparent mean of HH and LL lines. Data from the SD and CD environments were analyzed within environment using the GLM procedure of SAS (1985). The contrast option of this procedure was used to make specific comparisons. Statements of significance are (P<.01) unless otherwise indicated. Within environment, BW (by wk), percentage AF, and CLL data were analyzed with the following model:

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41

TABLE 3. Percentage heterosis in Japanese quail for crossline progeny within selection

environment1

Environment Trait

Age

Split

Complete

(wk)

0 1 2 3 4

8.2** 0 -11.1** -9.3** -9.0**

0 0 -7.5** -7.6** -6.7**

Percentage abdominal fat

-30.6**

-38.9**

Percentage carcass lipid

-17.0**

-24.0**

Feed efficiency, gain:feed

-8.1 -12.5* -9.1* 0

Body weight, g

-1.9 -2.6

Water consumption, g/bird/day

-1.7 2.0 6.7 0

-10.7 4.4 -8.2 -2.0 -1.0 -4.0

Feed consumption, g/bird/day

11.1 5.3 9.9* -4.8

0 -1.3 3.8 -5.6

Protein-diet consumption, g/bird/day

4.4 -8.3 2.6 -27.0**

Energy-diet consumption, g/bird/day

14.3 18.0** 15.3* 2.2

1 Percentage deviation of crossline (HL and LH) mean from pureline (HH and LL) mean. H = High BW; L : low BW.

*P<.05. **P<.01.

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both SD and CD environments (Table 3). Strong negative heterosis for progeny from HH and LL crosses of Japanese quail (Wyatt et al., 1982) and chickens (Barbato et ah, 1983) was found for abdominal fat and fat and lipid-related parameters. In contrast, strong positive heterosis for adult body fat was found in progeny from crosses of inbred strains of White Leghorns selected for high egg production (Abplanalp et al., 1984). Also, positive (25 day) and negative (61 day) heterosis for abdominal fat was found in progeny from high weight male x low weight female crosses of White Plymouth Rock lines by Cherry et al. (1987). These authors also found similar responses in heterosis for abdominal fat in hybrid progeny from crosses of the

Abdominal Fat and Carcass Lipids. Quail from HH lines had significantly higher percentage AF than quail from LL lines at 4 wk of age in the SD and CD environments (Table 2). These data are in agreement with differences between HH and LL quail in AF and CLL within SD and CD environments in earlier generations (Darden and Marks, 1988b). The HL and LH quail within SD and CD environments did not differ in percentage AF and CLL at 4 wk of age (Table 2). In the SD environment, HL and LH quail were intermediate to the parent lines in AF, although they were not greatly different from LL quail (Table 2). There was significant (P<.01) negative heterosis for AF (31 to 39%) and CLL (17 to 24%) in HL and LH quail in

42

DARDEN AND MARKS

LL lines in both SD and CD environments (Table 4). Darden and Marks (1988b) found similar within-environment differences between HH and LL lines for TFC data in earlier generations. Quail crosses (HL and LH) were intermediate in TFC to values of parent lines. The LH quail had higher TFC than HL quail, with a significant difference only during Week 1 in the CD environment. Negative and positive trends for heterosis corresponded to trends for heterosis in W intake and BW in these lines (Table 3). In the SD environment, W:TFC ratios (data not shown) were significantly higher in HH than LL quail at 1 wk of age. Quail from the HH lines were lower in W:TFC ratios than LL quail from 2 to 4 wk of age; differences were significant in the 3 and 4-wk data. In the CD environment, W:TFC ratios for HH quail were significantly greater than those for LL quail through 4 wk of age. The HL and LH quail in both SD and CD environments were usually intermediate in W:TFC ratios to those of HH and LL quail. In SD and CD environments, there were both positive and negative patterns for heterosis of W:TFC ratio data through 3 wk of age. Protein Diet Consumption. In the SD environment, PDC for HH quail was significantly higher than for LL quail (Table 5). Protein diet consumption peaked at Week 3 and declined thereafter. The PDC data of this study were consistent with data reported for SD environment quail in earlier generations (Darden and Marks, 1988b). The HL and LH quail were similar in PDC and intermediate in PDC to values of parent lines. There was a significant (P<.01) heterosis effect for PDC detected in HL and LH quail in Week 4. Energy Diet Consumption. In the SD environment, EDC for HH quail was higher than that for LL quail, with significant differences after 1 wk of age (Table 5). The differences between EDC in HH and LL lines agree with the EDC data reported for quail in earlier generations (Darden and Marks, 1988b). The HL quail were intermediate to parent lines in EDC whereas LH quail had slightly higher EDC than either parent line through 2 wk of age. Heterosis for EDC was positive and significant (P<.01) during Week 2. Heterosis for total feed consumption in the SD environment, however, appeared to be influenced more by EDC than PDC. This was in agreement with the EDC:PDC ratio data of Darden and Marks (1988b). These authors found quail from the LL line in the SD environ-

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high weight White Plymouth Rock line males with Single Comb White Leghorn females selected for low antibody response to sheep erythrocytes. Similarly, physiologically immature and mature hybrid progeny from normal high and low weight line reciprocal crosses exhibited minor negative and positive heterosis for percent abdominal fat and carcass lipids (Zelenkaef al., 1987). Feed Efficiency. Feed efficiency for HH quail was significantly higher than for LL quail through 4 wk of age in both SD and CD environments (Table 2). These differences between lines within environment for feed efficiency agree with FE data of earlier generations (Darden and Marks, 1988b). Quail crosses (HL and LH) were intermediate in FE to values for parental lines within both SD and CD environments. Although in both the SD and CD environments differences between FE of the HL and LH lines were not significant, early FE (Weeks 1 and 2) were higher in LH quail. Although heterosis for FE was predominantly negative (Table 3), the magnitude (0 to 12%) was not as great as the negative heterosis for AF and CLL (17 to 39%). These data appear in conflict with those of Barbato et al. (1983); strong positive heterosis for feed efficiency was associated with negative heterosis for BW of birds through 2 wk of age. Also, these data were not consistent with reports of Wyatt et al. (1982), who proposed that the heterosis in feed utilization was reflected by heterosis for fat deposition. Water Consumption. Quail from HH lines consumed significantly more W than quail from LL lines within both SD and CD environments (Table 4). Differences between W consumption of lines within environments were consistent with those found in earlier generations (Darden and Marks, 1988b). The HL and LH quail were intermediate to parent lines in W consumption in both SD and CD environments. In the SD environment, LH quail consumed significantly more W than HL quail from 0 to 3 wk of age. However, in the CD environment, LH quail consumed significantly more W than HL quail only during Week 1. There were no consistent trends for heterosis (-8.2 to 6.7%) for W consumption in crossline quail (Table 3). The positive and negative trends in LH and HL quail for heterosis in W consumption were also observed for heterosis in BW. Feed Consumption. Quail from HH lines exhibited significantly greater TFC than quail from

43

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TABLE 5. Protein and energy diet consumption for pure (HH and LL) and cross (HL and LH) Japanese quail aged I to 4 weeks old in the split diet environment1 Protein diet

Energy diet

Line

1 wk

2 wk

3 wk

4 wk

1 wk

2 wk

3 wk

4 wk

Pureline

HH LL

2.9 A 1.6B 2.3X

5.3 A 1.9B 3.6 X

5.9 A 1.9B 3.9 X

6.0 A 3.7 Y

1.5 A 1.3 A 1.4X

4.7A 3.0 B 3.9 Y

9.2 A 5.1 B 7.2 X

11.4 A 6.5B 9.0 X

A

2.2 2.7 A 2.4 X

A

3.2 3.4 A 3.3 X

4.1A 3.9 A 4.0 X

2.5A 2.9 A 2.7 X

1.5 A 1.7A 1.6X

4.3A 4.8A 4.6X

7.8 A 8.7 A 8.3 X

9.1A 9.3A 9.2 X

.15

.33

.40

.45

.05

.21

.44

.46

X

Crossline

SEM

HL LH x"

A,B Means within diet and mating type with different superscripts are significantly different (P<.01). Means (x purelines vs. x crosslines) within diet with different superscripts are significantly different (P<.01). 1 H = High BW; L = low BW.

merit to consume significantly more energy diet per volume of protein diet than quail from the H line. Differences between HH and LL lines within SD and CD environments for BW, RGR, AF, CLL, W, TFC, and FE were similar to the differences between these lines within their respective environments in earlier generations (Darden and Marks, 1988b). Negative heterotic effects in crossline progeny for BW after Week 1 were similar to negative effects for FE. Heterotic effects for W and TFC were both positive and negative and nonsignificant. Heterotic effects for AFand CLL, however, were highly negative and corresponded to negative trends for heterosis in feed efficiency. Using strains or strain crosses of poultry that exhibit the greatest amount of negative heterosis for AF and CLL may be one method to circumvent the problem of excess abdominal fat. REFERENCES Abplanalp, H., C. Tai, and D. Napolitano, 1984. Differences in body fat of six inbred lines of White Leghorns derived from a common base population. Poultry Sci. 63:418-424. Barbato, G. F., P. B. Siegel, and J. A. Cherry, 1983. Selection for body weight at eight weeks of age. 16. Restriction of feed and water. Poultry Sci. 62:19441948. Barlow, R., 1981. Experimental evidence for interaction between heterosis and environment in animals. Anim. Breed. Abstr. 49:715-737. Bell, A. E., 1982. Selection for heterosis-results with laboratory and domestic animals. Proc. 2nd World Congr.

Genet. Appl. Livest. Prod. 6:206-227. Bernon, D. E., and J. R. Chambers, 1985. Maternal and sex-linked effects in broiler parent stocks. Poultry Sci. 64:29-38. Cherry, J. A., I. Nir, D. E. Jones, E. A. Dunnington, Z. Nitsan, and P. B. Siegel, 1987. Growth-associated traits in parental and F, populations of chickens under different feeding programs. 1. Ad libitum feeding. Poultry Sci. 66:1-9. Cock, A. G., and J. R. Morton, 1963. Maternal and sexlinked effects on size and conformation in domestic fowl. Heredity 18:337-350. Cunningham, E. P., 1982. The genetic basis of heterosis. Proc. 2nd World Congr. Genet. Appl. Livest. Prod. 6:190-205. Darden, J. R., and H. L. Marks, 1988a. Divergent selection for growth in Japanese quail under split and complete nutritional environments. 1. Genetic and correlated responses to selection. Poultry Sci. 67:519-529. Darden, J. R., and H. L. Marks, 1988b. Divergent selection for growth in Japanese quail under split and complete nutritional environments. 2. Influence of selection for growth on water and feed intake patterns, abdominal fat and carcass lipid characteristics. Poultry Sci. 67:1111-1122. Folch, J., M. Lees, and G. H. Sloane-Stanley, 1957. A simple method for the isolation and purification of total lipids from animal tissues. J. Biol. Chem. 226:497-509. Griffing, B., and E. Zsiros, 1971. Heterosis associated with genotype-environment interactions. Genetics 68:443455. Hayes, H. K., F. R. Immer, and D. C. Smith, 1955. Heterosis. Pages 52-65 in: Methods of Plant Breeding. 2nd ed. McGraw-Hill Book Co., Inc., New York, NY. Lewis, D., 1954. Gene-environment interaction: A relationship between dominance, heterosis, phenotypic stability and variability. Heredity 8:333-356. Marks, H. L., 1973. Performance of crosses of quail selected under different environments. Heredity 64:73-76.

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Mating

HETEROSIS IN GROWTH-SELECTED QUAIL

standard females on performance of broilers. Poultry Sci. 62:1521-1522. (Abstr.) Washburn, K. W., and D. F. Nix, 1974. A rapid technique for extraction of yolk cholesterol. Poultry Sci. 53:1118-1122. Wright, S., 1977. Evolution and the Genetics of Populations. Vol. 3. Experimental Results and Evolutionary Deductions. The Univ. Chicago Press, Chicago, IL. Wyatt, J.M.F., P. B. Siegel, and J. A. Cherry, 1982. Genetics of lipid deposition in Japanese quail. Theor. Appl. Genet. 61:257-262. Zelenka, D. J., D. E. Jones, E. A. Dunnington, and P. B. Siegel, 1987. Selection for body weight at eight weeks of age. 18. Comparison between mature and immature pullets at the same live weight and age. Poultry Sci. 66:41-^16.

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