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Two experiments were conducted to investigate the relationships among reproductive performance, serum gamma-globulin level, carbon clearance ability, and immune responses to phytohemagglutinin and SRBC in the Taiwan Country chicken. In Experiment 1, 480 pullets from 82 sires and 204 dams were used to evaluate the relationship between reproductive performance and immunity. In Experiment 2, 480 pullets, offspring from 55 sires and 173 dams expressing a high or low percentage of serum gamma-globulin and their reciprocal crosses, were used to examine if the level of serum gamma-globulin is associated with reproductive performance and immunity. Results of these experiments indicated that 1) the Taiwan Country chicken had relatively high serum gamma-globulin level compared with those in other reports, 2) serum gamma-globulin level in the Taiwan Country chicken is heritable with an estimate around 0.3 to 0.4, and 3) the high serum gamma-globulin level is genetically associated with low fertility.

Turkey hens were artificially inseminated at three times (0800, 1100, or 2200 hr) under conditions where high or low fertility would be expected. Four trials were conducted and the same two persons collected semen and inseminated the hens in all trials. Each hen was inseminated with .025 cc undiluted semen. There was no significant difference in fertility when hens were inseminated at different times of the day in the first three trials. In a fourth trial, where high fertility was expected, hens inseminated at 0800 hr had lower fertility than those inseminated at 2200 hr. There was no significant difference between inseminating at 0800 or 1100 hr and 1100 or 2200 hr. The results of this study indicate that late evening insemination is not necessary for high fertility.

MORE losses occur in duck eggs (Horton, 1932) than in chicken eggs (Hafez and Kamar, 1955), during the incubation period, either due to low fertility (Fronda, Zialcita and Dalisay, 1940; Pozo Lora, 1959), or low hatchability (Pritsker, 1941). Ducks, in general, have a restricted breeding season and lay relatively few eggs. Accordingly, it is important to reduce these losses to a minimum to use the reduced number of eggs to produce the highest number of ducklings possible. Seasonal variation occurs in fertility of Khaki Campbell duck eggs. An increase in atmospheric temperature causes the decrease in fertility, while an increase in normal day length causes a rise in fertility when the atmospheric temperature is relatively low (Pozo Lora, 1959). The normally low fertility in Khaki Campbell could be improved by supplemental artificial light summing up to 14 hours of light daily when the atmospheric temperature was relatively low (Pozo Lora …

INTRODUCTION SELECTING breeding males that have a high fertilizing capacity is a matter of considerable economic importance, as pointed out by Parker (1949), who estimated that about 10 to 15 percent of all chicken eggs incubated are infertile. Hays and Sanborn (1939) indicated that the male may be largely responsible for infertility since by rotating males in pens that were low in fertility, fertility was increased considerably. Lamoreux (1940) and Sampson and Warren (1936) observed that artificial insemination of infertile females increased the fertility of these birds. It has been shown by some investigators that the libido of the male is related to fertility. Wood-Gush and Osborne (1956) selected the five cockerels highest in sex drive from a group and noted that they fertilized more females than the five lowest males. Craig, Casida and Chapman (1954) observed a strain of rats with low fertility and attributed the low fertility to …

INTRODUCTION LOW fertility in eggs is a characteristic phenomenon commonly observed in summer hatches of fowl eggs in subtropic countries like Egypt (Hafez and Kamar, 1955). This may be due to a lot of factors, of which the most important one may be the male side when represented by semen production. This work was done in a trial to improve the characteristics of semen produced by the cocks by administering thyroprotein as a replacement for the decreased thyroidal activity that was observed to occur during hot weather (Winchester, 1940; and Reineke and Turner, 1945). This hot weather normally occurs during the summer in Egypt. Hyperthyroidism induced by feeding thyroprotein (0.02%) for a 16 week period to two year old Barred Rock males, did not affect semen volume or sperm concentration. However, there was some deterioration in methylene blue test, motility of spermatozoa and survival time at 4°C. and hence lowered …

AMONG the economic problems in turkey production are low fertility and hatchability. Friars et al. (1963) noted that for all turkey eggs set in the U.S. and Canada, the hatchability was in the range of 55 percent. Hale (1951) reported that infertility was due to low effectiveness of males in inseminating the females. The female's sex drive was reduced by incomplete copulation comparable to hens with which complete matings took place. Effectiveness ranged from 15 to 97% of the attempted copulations. The average interval between matings following complete copulation was 9 days (3–17) compared to incomplete copulation of 7 days (2–12). Smyth and Leighton (1953) reported total matings completed by 7 males showed a variation of 44.3 to 87.5% of matings completed with an average of 68.2%. Males with high efficiency possessed a good sense of balance, showed considerable patience and completed the matings with a minimum of . . .

THE problem of fertility in chickens has been studied by many investigators who have contributed much valuable information. During recent years, however, under improved methods of breeding more information has accumulated to indicate that low fertility is still an important problem of the poultry breeder. Even at the present time there is disagreement regarding the role that heredity may play here. There would therefore seem to be ample justification for further study of the inheritance phase of the problem in a closed flock. LITERATURE REVIEW Pearl and Surface (1909) found no evidence that fertility was inherited. Jull (1935) reported the correlation between the fertility of dams and the fertility of their daughters to be .19±.05 which was probably significant but far from intimate. Hays and Sanborn (1939) calculated the simple correlation between 466 mothers and 1452 daughters in fertility and obtained a value closely approaching zero. Incompatibility was first emphasized . . .

DURING the course of some investigations on the effect of male to female ratios on fertility in flock matings of chickens, it was observe d that when Dar k Cornish cockerels were mated to New Hampshire pullets, fertility appeared to be lower than when either Delaware or New Hampshire cockerels were used (Parker, 1958a). Increasing the relative numbers of Cornish males in the flocks from four to as many as eleven per 100 females did not increase fertility. The purposes of the following investigations were to compare the fertilizing capacity of Dark Cornish males with that of New Hampshire, Delaware, and Cornish × New Hampshire crossbred males in controlled experiments and to attempt to determine the factor or factors contributing to the differences in fertility. FERTILITY IN FLOCK MATINGS To compare the fertilizing capacity of Cornish cockerels with that of New Hampshire and Delaware cockerels three pens of approximately 100…

SINCE Salmonella pullorum has been frequently incriminated as a cause of low fertility and hatchability of eggs, it has been considered possible that other microorganisms which have been isolated from eggs or oviducts might have a similar injurious effect upon hatchability of eggs. Experiments at the Illinois Agricultural Experiment Station have, therefore, been conducted to determine the effect of inoculating eggs with suspensions of the following microorganisms: Salmonella pullorum, Salmonella aertrycke, Salmonella gallinarum, Pasteurella avicida, two strains of staphylococci isolated from eggs of apparently healthy hens and three strains of streptococci isolated from eggs of apparently healthy hens. TECHNIC EMPLOYED All eggs 1 used in these studies were purchased from a flock that had been pullorum tested over a period of several years, but it is not assumed that all eggs were free from S. pullorum. Each setting of eggs was divided into either three or five groups. When the three-group . . .

THE low fertility characteristic of White Wyandottes is associated with rose comb and is expressed only by males homozygous (RR) for that comb type (Crawford and Merritt, 1963; Crawford and Smyth, 1964a). Presence of the gene for rose comb in the sperm cell does not decrease fertility of that cell; instead, the low fertility is caused by some deleterious effect of the RR male host body acting on the spermatozoa (Crawford and Smyth, 1964b). To determine whether this effect might be identified in the semen, several experiments have been conducted to compare qualities of semen and seminal plasma of males of RR, Rr, and rr comb genotypes. A possible reason for the low fertility of RR males is that some inadequacy might exist in their seminal fluids. One or more of the essential components may be absent or present in insufficient amounts preventing normal fertility from being expressed. Maw (1954) has described a condition of this nature, regulated…

Low fertility in turkeys is a major problem. Since poults are produced throughout the year in some localities, high fertility during the fall and winter months has become increasingly important. Concern about comparative productiveness of individual males during the “out-of-season” period prompted this study. REVIEW OF LITERATURE Hays (1950) after 10 year's research with Rhode Island Reds concluded that sex-linked genes may regulate fertility, Blow et al. (1951) reported that fertility in turkeys was only slightly heritable. Carson and Lorenz (1953) found that Broad Breasted Bronze males usually began producing semen when from 213 to 225 days old. Semen production increased gradually until late the following summer when it decreased gradually. Carson et al. (1955a), working with 187 Broad Breasted Bronze males which were neither housed nor kept in artificially lighted areas for 2 years, found males began producing motile sperm at 132 to 291 days of age. Semen production…

LOW fertility has been a problem of economic importance to the poultry industry for many years. It is a conservative estimate that 10 to 15 percent of all eggs set are infertile. This represents a large monetary loss to poultrymen each year. There are at least three ways to solve this problem: (1) find a method to detect infertile eggs before they are set, there being no practical method at present; (2) increase the fertility of eggs set by genetic means; or (3) increase the fertility of eggs set by providing optimum environmental conditions for the expression of this character. The results herein reported provide further information on environmental factors affecting fertility. The objectives of these experiments were: (1) to study the effect of dubbing males on their mating activity and fertility; (2) to study the effect of environmental temperature on mating activity and fertility; (3) to study the relationship . . .

FERTILITY has been shown to be highly correlated with certain semen measurements in chickens under conditions of artificial insemination (Cooper and Rowell, 1958). Their results indicate that fertility of individual cocks may be predicted relatively well from the semen measurements of motility, percentage of dead spermatozoa, and reduction time. Reduction time is a measure of metabolic activity and is accomplished by the mixing of a given amount of semen with a resazurin solution and recording the time required to reach a pink end point. The technique is described by Cooper and Rowell (1958). Density of live spermatozoa also was significantly correlated with fertility but it had less predictive value. Other studies (Parker et al, 1942; Shaffner and Andrews, 1948; Allen and Champion, 1955; and McDaniel and Craig, 1959) support various aspects of these general results. The present investigation supplies further evidence on the relative magnitude of correlations of resazurin reduction …

BREEDERS in recent years have made remarkable improvement in mature body weight, growth rate and conformation of turkeys. It is well known that the commercial strains which rank highest in the characters mentioned above suffer almost without exception from low fertility. This has been attributed by some to incompatibility of body shape and size to the natural act of mating. It is probably true that a small turkey resembling the “wild” type is less awkward and, therefore, more efficient in performing the mating act than a large broad breasted turkey. Some large turkey males of excellent meat type have been observed to mate efficiently, however, so that the possibility suggests itself that defective mating behavior and/or low fertility is a result of lack of selection for these factors on the part of breeders. Much of the improvement which has been made in the highly heritable traits such as size and …

Three experiments were conducted to study the effects of blood sera and uterine fluids, from turkey hens immunized against turkey semen, on the fertilizing ability of sperm cells. Sperm cells were incubated in the test materials (blood sera, uterine fluids or control diluents) and then inseminated into recipient hens. Pooled sera from immunized hens significantly reduced the fertilizing ability of the sperm cells, while sera from non-immunized hens did not. Uterine fluid from all groups severely reduced the fertilizing ability of spermatozoa. Virgin hen uterine fluid was slightly, but not significantly, less harmful to spermatozoa than uterine fluid from birds exposed to spermatozoa (either by artificial insemination of AI preceded by immunization). Sera from individual immunized and non-immunized hens was tested for anti-fertility effects. Sera from 3 immunized hens with histories of low fertility severely depressed the fertilizing ability of spermatozoa. Sera from 2 immunized hens with histories of high fertility had no effect on the fertilizing ability of sperm cells, while sera from one of these hens depressed it. Virgin hen sera had no significant effect on the spermatozoa. Uterine fluids from high and low fertility immunized hens were dialyzed against a buffer. Aliquots of the dialyzed material from high and low fertility birds were heated to destroy antibodies. These fluids were used as semen diluents. The unheated fluid from low fertility hens significantly depressed fertilizing ability of sperm cells.

THE incidence of low fertility in turkey breeding flocks has created a serious problem for the turkey industry. At the present time relatively little is known about the factors contributing to infertility in the turkey. The fact that our knowledge of fertility in the chicken following forty years of investigation of this subject remains incomplete indicates that the problem of avian fertility is not a simple one. In the past few years a number of studies have provided information concerning some of the factors which appear to contribute to apparent infertility. Wilcke (1939) and Milby and Thompson (1945) reported that preferential mating was frequently responsible for low fertility in single male matings. It was also noted by Milby and Thompson (1945) that some hens remained infertile after rotation of the toms. However, Hale (1951) observed that although the differential fertility of female turkeys typically fitted the criterion of preferential mating, …

Semen samples from groups of males chosen for high or low freezability of semen were frozen by two different methods, one using glycerol as the cryoprotectant and the other using DMSO. Fertilizing capacity was highest from semen collected from males of the high group and frozen in the presence of DMSO. Neither semen source nor method of freezing had any influence on the hatch of fertile eggs.

MOST comparisons of Bronze or Broad Breasted Bronze with smaller breeds show that hatchability of all eggs set is lower for the larger variety (Sampson and Wilson, 1944; Walter and Hoffman, 1947; Marsden and Olsen, 1950). Somewhat poorer results from hatch of all eggs were reported from larger than from smaller Bronze hens by Funk (1950) although Parker and Harper (1950) found no convincing evidence of such differences among somewhat smaller Bronze hens. Fertility is at times a factor in the low hatchability of turkey eggs and when such low fertility occurs in healthy flocks it can be improved by artificial insemination (Stotts and Darrow, 1955). The experiment reported here was designed to compare fertility and hatchability of hen and tom turkeys of different weights in a commercial flock of Broad Breasted Bronze turkeys under conditions of supplemental insemination. EXPERIMENTAL PROCEDURE The Broad Breasted Bronze hens were divided into six …

Level of damage caused by freezing and thawing to four spermatozoal organelles (individual mitochondrion, midpiece, nucleus, and perforatorium) and the relationships of the integrity of these organelles in fresh and frozen-thawed semen with fertility were examined. Semen sample from 10th generation males of a line of chickens selected for increased duration of fertility of frozen-thawed semen and the corresponding randombred control line were used. In both the selected and control lines, the freeze-thaw process caused significant (P less than .05) detrimental damage to the ultrastructure of the mitochondria, midpiece, and perforatorium but not to the nucleus. Types of damage were identical in both lines. Granulated nuclei were observed in both frozen-thawed and freshly ejaculated spermatozoa and were referred to as a nuclear defect. This nuclear defect was associated with reduced fertility, the effect being more severe with frozen-thawed semen. Where the incidence of the nuclear defect was greater than 2% in frozen-thawed semen, fertility was found to be very low or nil regardless of the degree of structural integrity of the mitochondria, midpiece and perforatorium. Highly significant (P less than .01) positive correlation coefficients were observed for percentage fertility 2 to 8 days postinsemination and duration of fertility in days with percentages of normal mitochondria (.80 and .92), midpiece (.79 and .87), nucleus (.86 and .94), and perforatorium (.84 and .97) for fresh semen. With frozen-thawed semen, the positive correlation coefficients were significant (P less than .05) for midpiece (.64 and .69) and nucleus (.63 and .71) and nonsignificant for mitochondria (.52 and .50) and perforatium (.20 and .30).(ABSTRACT TRUNCATED AT 250 WORDS)

LOW fertility is still a serious problem in producing turkey hatching eggs even though most turkeys are artificially inseminated. Generally, the fertility of turkey eggs is relatively high at the beginning of the breeding season and then declines as the season progresses. Several factors may be responsible for the seasonal decline in fertility. Among these are faulty insemination techniques, as shown by Ogasawara and Rooney (1966), and mechanical spread of infectious organisms from hen to hen by the insemination technique. Many turkey breeders and turkey hatching egg producers are now using a disposable plastic tube for insemination in order to prevent spread of vaginal infection. Although the use of the tube method of insemination has become an established practice commercially, there has been little experimental evidence to show that it is a superior method. In a preliminary report of the present work, Nestor and Brown (1966) observed that the tube . . .

EXTENSIVE studies have been conducted on the effects of the autosomal dominant gene for rose comb (R) on reproductive ability in domestic fowl. Crawford and Smyth (1964a) have shown that reproduction is faulty only in RR males, heterozygotes and homozygous recessive single-combed (rr) males being normal; females of all three genotypes reproduce equally well. The defect in RR males is expressed mainly as a reduction in fertility and in duration of fertility (Crawford and Smyth, 1964a, b). Petitjean and Cochez (1966) found that motility of sperm from RR males was decreased following in vitro storage. Reduced fumarase activity in sperm from RR males was subsequently demonstrated by Buckland et al. (1969), which may account for the observed low fertility. Nearly all of the reported studies have utilized the rose comb gene as obtained directly or indirectly from the Wyandotte breed. It has been of interest to consider whether the gene…

RECENTLY there has been rather wide-spread interest among commercial breeders in the use of artificial breeding to improve the reproductive efficiency of many low-fertility strains of turkeys. In order to make artificial breeding as efficient as possible for commercial application, it is important to be able to provide sound recommendations concerning the frequency of mating by artificial insemination with various levels of semen. Generally, it is recommended that poult producers inseminate their breeders with either 0.05 or 0.025 ml. of undiluted semen at intervals of either two or three weeks. Therefore, the present study was undertaken to relate frequency of mating and semen dosage to reproductive performance. McCartney (1952) has previously reviewed the literature concerning the relationship between frequency of mating by artificial insemination and semen dosage and resultant fertility in turkeys. He also reported results from mating turkeys with successive insemination of 0.05 ml. of semen at intervals of …

Low fertility and low hatchability are common faults of certain strains of Broad Breasted Bronze turkeys. The ultimate solution of this problem probably depends on additional emphasis on hatchability as part of a long-term breeding program. There is need however, for an interim solution of the problem. The following evidence indicates that crossbreeding may be a suitable technique for the immediate improvement of fertility and hatchability. Byerly, Knox, and Jull (1934), concluded that crossbreeding in chickens is likely to increase hatchability if breeds of low hatchability are crossed but not if the parental stock averaged above 80 percent in hatchability. Clark, Runnels, and Livesay (1944), reported a singificant increase in hatchability but not infertility when reciprocal crosses were made between Broad Breasted Bronze and Bronze, Bourbon Red, and Black varieties of turkeys. There was evidence, however, that matings of B.B. Bronze toms with hens of the medium sized varieties resulted . . .