Effect of bovine serum albumin on motility and fecundity of turkey spermatozoa before and after storage.

Motility characteristics of turkey spermatozoa before and after storage for 24 h at 7 degrees C in diluent with and without bovine serum albumin (BSA; 1% final concentration) were measured by computer-assisted semen analysis. BSA significantly increased the percentage of motile spermatozoa and sperm velocity, linearity, lateral head displacement and beat frequency in each treatment, but BSA in fresh or stored semen in diluent did not augment hen fertility over 15 weeks of egg production. Fatty-acid-free BSA, globulin-free BSA and Fraction V BSA all significantly increased each sperm motility characteristic compared with semen in diluent alone. The lack of correlation between sperm motility and fecundity emphasizes the need to develop procedures for semen evaluation that accurately predict the fertilizing capacity of an aliquot of semen.

Research note: effects of agitation and temperature changes on turkey sperm viability after twenty-four hour storage.

The effects of agitation and temperature changes on turkey sperm viability were estimated before and after 24 h storage at 7 C using the ethidium bromide (EB) procedure and a sperm stress test. The stress test is identical to the EB procedure except the buffer is hypotonic. Labile sperm lyse and are then stained with the EB. Treatments consisted of semen diluted 1:1 and subjected to one of the following procedures: agitation (pipetting up and down 25 times, repeated 4 times at 15-min intervals); temperature changes (semen moved from 7 to 26 C and back to 7 C 3 times at 30-min intervals); or control semen procedures (diluted semen is placed on an orbital shaker at 7 C). Each semen treatment was evaluated within 3 h of dilution and after 24 h storage. Agitation and temperature changes did not affect viability of sperm. Regardless of treatment, the EB procedure revealed no differences in sperm viability before or after 24 h storage. In contrast, the same samples subjected to the stress test revealed significant increases in nonviable sperm after 24 h storage. However, there was no treatment by test interaction. These data indicate that mixing semen with diluent and mild changes in semen temperature associated with the transport of semen between the interval of semen collection to insemination, even up to 24 h storage, have minor effects on sperm viability.

Correlations of organ weights, hematocrit, and testosterone with sexual maturity of the male turkey.

A study was conducted with Large White breeder male turkeys to determine changes in blood constituents and organ weights associated with sexual maturity. Testicular samples from 8- to 32-wk-old turkeys were histologically examined and the changes in the seminiferous tubule epithelium associated with sexual maturity were correlated with changes in blood constituents and organ weights. Spermatozoa were first found in the lumina of the seminiferous tubules at 15 wk, and semen containing mature spermatozoa was first observed in the ductus (d.) deferens at 26 wk. Testes weights increased significantly between 20 and 22 wk and continued to increase until 30 wk of age. Testosterone concentration in the blood was .2 ng/mL at 16 wk, and steadily increased to 1.3 ng/mL at 34 wk. The increase in testosterone paralleled the increase in testes weights. The bursa of Fabricius weight reached a maximum at 16 wk, began to regress at 22 wk, and was completely regressed at 32 wk. Hematocrit values started to increase at 16 wk and reached a plateau at 22 wk. The association of the increase in hematocrit with the functional maturation of the testes suggests that the increase in hematocrit could be used to predict maturation of testicular spermatozoa in the male breeder turkey. However, semen production (semen accumulation in the d. deferens) did not start until 10 wk after mature spermatozoa were found in the testes.

Modification of the ethidium bromide exclusion procedure for evaluation of turkey semen.

The objective of the present study was to modify the ethidium bromide exclusion procedure in order to detect dead and labile turkey spermatozoa after 24 h storage at 7 C. In Experiment 1, fresh and stored spermatozoa were suspended in phosphate-buffered saline (PBS) ranging in osmolarity from 296 to 3 mOsm/kg H2O, each solution containing the same concentration of the nuclear fluorochrome ethidium bromide. In the 3 mOsm/kg H2O PBS, nearly all the fresh (98.3%) and stored (96.7%) spermatozoa were stained with ethidium bromide, indicating they were nonviable. Fresh spermatozoa revealed minor variation in the percentage of nonviable spermatozoa in the ethidium bromide exclusion procedure (ethidium bromide in PBS at 296 mOsm/kg H2O) (20.9%) and the remaining hypotonic PBS solutions (range 20.4 to 18.9%). In the stored semen samples a previously undetected subpopulation of more labile spermatozoa became apparent in hypotonic solutions with osmolarities of 122 and 56 mOsm/kg H2O. In Experiment 2, hen fertility was determined using fresh and stored semen. All hens were inseminated with 100 x 10(6) viable spermatozoa. Viability of stored semen was determined either by the original ethidium bromide exclusion procedure or using the sperm-stress test (ethidium bromide in PBS at 56 mOsm/kg H2O). The observations showed that adjusting the number of viable spermatozoa inseminated based on the percentage of viable sperm estimated from the sperm-stress test did not improve hen fertility over a 15-wk egg production period.

Effect of the presence of hens on the semen production of male breeder turkeys.

Large White breeder male turkeys were raised in the absence of females. At 28 wk of age, the breeders were moved to a house with two separate wings. In one wing, four pens with five males per pen were alternated with 4 pens of breeder females; in the other wing, 4 pens with 5 males per pen were alternated with 4 empty pens. Vocalization by the females could not be heard in the wing without females. Semen was collected once a week from 33 to 49 wk of age. The ejaculate volume, concentration of spermatozoa in the ejaculate, and total number spermatozoa per ejaculate were determined for each male. An analysis of variance for each week showed few significant effects (P less than .05). Males with females in adjacent pens had higher ejaculate volumes and higher totals for spermatozoa per ejaculate for Weeks 36 and 41, higher spermatozoal concentrations for Week 39, and a lower spermatozoal concentration for Week 44 than males adjacent to empty pens. For Weeks 33 to 49 inclusive, the cumulative total ejaculate volume per male was 5.18 and 4.89 mL, and the cumulative total spermatozoa per male was 40.0 and 39.0 billion for males adjacent to females and males adjacent to empty pens, respectively. Therefore, the authors concluded that the presence of breeder hens had little effect on ejaculate volume, on concentration of spermatozoa in the ejaculate, or on total spermatozoa per ejaculate of breeder male turkeys.

Testosterone concentrations in blood and seminal plasma of turkeys classified as high or low semen producers.

The interrelationships between concentrations of testosterone in blood plasma, seminal plasma (SP) of ductus (d.) deferens semen, and SP of the ejaculate of mature breeder turkeys were compared. The concentration of testosterone in blood plasma was greater than, and positively correlated with (r = .75, P less than .01), the concentration of testosterone in the ejaculate SP and d. deferens SP. Differences between concentrations of testosterone in blood plasma, ejaculate SP, and d. deferens SP were not significantly different for turkeys classified as high (ejaculate volume greater than .38 mL) or low (ejaculate volume less than .26 mL) volume semen producers. Concentrations of testosterone in blood plasma and SP were not correlated with ejaculate spermatozoal concentration, total number of spermatozoa, d. deferens semen volume, or testicular weights.

Daily output of spermatozoa and extragonadal spermatozoal reserves in turkeys.

Daily spermatozoal output (DSO) was estimated by determining the total number of spermatozoa in ejaculates of male line breeder turkeys ejaculated daily for 15 days. The DSO was constant at 520 million spermatozoa after the first 6 days of semen collection. Testicular spermatozoal reserves (TSR) and extragonadal sperm reserves (EGR) were measured 24 h after the last semen collection from turkeys ejaculated 1 x/day for 15 consecutive days (ejaculated) and 21 days after the last semen collection from turkeys previously ejaculated 1 x/wk for 12 wk (rested). The TSR concentrations were similar (P greater than .05) for ejaculated and rested groups, respectively: 117 x 10(6) and 119 x 10(6)/g for right testis; 127 x 10(6) and 135 x 10(6)/g for left testis. The total TSR were also similar (P greater than .05): 3,308 x 10(6) (ejaculated) and 4,343 x 10(6) (rested). However, EGR for ejaculated and rested groups were significantly different, with the following values, respectively: ductus deferens, 3,160 x 10(6) and 10,320 x 10(6) (P = .0005); epididymis, 58 x 10(6) and 204 x 10(6) (P less than .004); total EGR, 3,248 x 10(6) and 10,524 x 10(6) (P less than .005). This study shows that although TSR was not affected by daily semen collection, EGR was depleted by 70% of the rested value (P less than .005) when the turkeys were ejaculated daily for 15 days.

Effect of light intensity during the breeder period on semen production of low weight and normal weight breeder turkeys.

Semen production of low weight and normal weight breeder turkeys was compared when maintained on low or high light intensities during the breeder period. A flock of Large White male breeder turkeys was raised in two houses and received 12 hr of 54 lx incandescent light from 10 to 30 weeks of age. The average body weights of the 32-week-old males in the two houses were 12.6 (low weight) and 19.4 kg (normal weight), respectively. At 30 weeks of age the males were exposed to 15 hr of 6.5 lx (LL) or 100 lx (HL) incandescent light. The semen volume of the low weight males was less than that of the normal weight males during the first few weeks (Weeks 33, 34, 35, and 37), and during the last weeks of semen collection (Weeks 45 to 49, inclusive). Semen volumes of normal weight males were comparable for LL and HL, but semen volumes of low weight males were greater with HL than LL, particularly during Weeks 33 to 42. Body weight at 32 weeks of age or light treatment during the breeder period had no effect on sperm concentration, and, therefore, sperm per ejaculate paralleled semen volume. This study demonstrated that an increase in light intensity during the breeder period did not completely overcome the delay in the onset of semen production caused by low body weight gain during the adolescent period. However, because the overall total number of sperm in the ejaculate of low weight males on HL was greater than those on LL, increased light intensity may improve the sperm production of low weight males.

Embryonic development of the turkey male genitalia.

Embryonic development of male turkey genitalia was examined to define more clearly the origin of the structures comprising the Phallus nonprotrudens. At Day 7 of incubation, the knob-like genital (g.) eminence became evident just cranial to the tail fold. A raised caudal extension of the g. eminence, the g. crest, joined the tail fold medial to the paired g. swellings. Between Days 8 and 12 of incubation, the g. eminence differentiated into the g. tubercle (which by Day 18 formed the Phallus nonprotrudens), and the g. crest formed the ventral floor of the proctodeum. By Days 10 to 11 of incubation, the g. swellings had become confluent with the lateral extensions originating from the base of the g. tubercule forming both a collar-like structure around the vent and the dorsal wall of the proctodeum. By Day 23 of incubation, the urodeum and proctodeum had become patent and the overall anatomy of the genitalia resembled that of an immature male poult.

Volume, sperm concentration, and fertilizing capacity of turkey ejaculates obtained from successive cloacal strokes during semen collection.

Ejaculate fractions (EF), obtained as the ejaculate from each of four successive cloacal strokes (EF1, EF2, EF3, and EF4, respectively), were collected manually by abdominal massage from Large White breeder turkeys. Semen volume and sperm concentration were the greatest for EF 1 and decreased with each successive fraction. Ejaculate Fraction 1 and EF (1 + 2) represented 50 and 79% of the total sperm collected, respectively. Approximately 6, 9, 10, and 11 hens could each be inseminated with 200 X 10(6) sperm from semen collected from each male using EF1, EF (1 + 2), EF (1 + 2 + 3), and EF (1 + 2 + 3 + 4), respectively. There were no differences in duration of fertility, percentage fertility, or percentage hatchability of eggs from hens inseminated with semen from EF1, EF3, and pooled control semen samples.

Anatomy of the Corpus vasculare paracloacale of the male turkey.

The copulatory apparatus of the male turkey consists of two parts: the Phallus nonprotrudens, composed of the paired Corpora phallica lateralia and Plicae lymphaticae, and the paired Corpora vascularia paracloacalia. The Corpus vasculare paracloacale receives its vascular supply and drainage from the Arteria (A.) and Vena (V.) pudenda interna, respectively, and its innervation from the Nervus pudendus internus. During sexual stimulation lymph produced in the Corpora vascularia paracloacalia rapidly flows through the lymph sinuses into larger lymph channels located in the Phallus nonprotrudens producing tumescence. With detumescence, the lymph flows cranially from Phallus nonprotrudens into the Vasa lymphatica pudenda interna, which parallels the A. and V. pudenda interna.

Testicular weights, ductus deferens semen volumes, and sperm concentration of turkeys with high and low ejaculate volumes.

Studies were conducted to determine if high and low ejaculate volumes were associated with differences in testicular weight and ductus (d.) deferens semen volumes. Mature male breeder turkeys were classified as low (less than or equal to .22 ml) or high (greater than .30 ml) semen producers. One week after or immediately after the last semen collection the turkeys were killed, testes weighed, and d. deferens and ejaculate semen volumes and sperm concentrations determined. Comparisons of low (LSP) and high (HSP) semen producers showed no differences in testes weights and sperm concentration in d. deferens. However, LSP turkeys had a lower volume of semen in the d. deferens and ejaculated a lower percentage of that volume than did HSP turkeys (P less than .05). Although the sperm concentrations of HSP and LSP were the same, the total number of sperm in the ejaculate of LSP was less than the HSP and was also less when calculated as a percentage of the sperm in the ejaculate plus d. deferens. These studies indicate that both a decreased reservoir of semen in the d. deferens and a lower efficiency of removal of semen from the d. deferens contribute to the decreased ejaculate volume of LSP.

Effect of dietary protein and light restriction on body weight and semen production of breeder male turkeys.

The relationships of dietary protein, body weight gain, prebreeder light restriction, age at the start of semen production, and semen volume were studied. Large White breeder male turkeys were fed corn-soybean meal diets containing the following percentages of protein at different age intervals: Treatment A, 26% (8 to 12 weeks), 19% (13 to 18 weeks), 15% (19 to 52 weeks); Treatment B, 26% (8 to 12 weeks), 19% (13 to 18 weeks), 8% (19 to 52 weeks); Treatment C, 17% (8 to 28 weeks), 8% (29 to 52 weeks); Treatment D, 17% (8 to 18 weeks), 8% (19 to 52 weeks). Body weights at 18, 28, and 52 weeks of age were: Treatment A, 11.8, 20.8, and 21.7 kg; Treatment B, 11.4, 15.1, and 17.8 kg; Treatment C, 9.2, 20.0, and 20.7 kg; Treatment D, 9.1, 11.8, and 15.0 kg. The effects of 6 hr light: 18 hr dark (restricted light) were compared with 12 hr light: 12 hr dark (full light) during the prebreeder period (18 to 28 weeks of age). All turkeys received 14 hr light: 10 hr dark from 29 to 52 weeks of age. With full light, 50% of the turkeys were producing semen at 29 weeks and 100% at 32 weeks. With restricted light, 50% of the turkeys were producing semen at 32 weeks and 100% at 34 weeks. Turkeys fed Treatments A, B, C, and D reached 50% production at 28, 30, 29, and 32 weeks, respectively, and all turkeys were producing semen at 35 weeks. The average semen volume per ejaculate for weeks 34 to 52 were: .35, .34, .34, and .25 ml for Treatments A, B, C, and D, respectively; and .34 and .31 ml for full and restricted light, respectively. Treatments B and D reduced body weight gain after 18 weeks of age. However, Treatment B had better semen production than Treatment D. There was no advantage to restricted light during the prebreeder period.

Gross appearance of turkey cloacae before and after single or multiple manual semen collections.

The gross appearance of the turkey cloaca was examined before and after single or multiple semen collections. All cloacae exhibited some degree of hemorrhage formation, the extent of which was dependent upon 1) frequency of semen collection, 2) number of cloacal strokes, and 3) individual differences in semen collectors' techniques. Cloacae of males subjected to multiple semen collections of more than four cloacal strokes per semen collection were the most severely injured. Cloacae examined three days after the last semen collection were nearly normal in appearance. It is suggested that cloacal hemorrhages resulting from semen collection can be minimized by 1) reducing the number of cloacal strokes per semen collection to one or two and 2) using the correct hand placement and pressure on the cloaca during the cloacal strokes.

Histology of turkey papillae after manual semen collection.

Papillae from mature turkey males were removed before and after semen collection and examined by light microscopy. The surface mucosa consisted of deeply folded columnar epithelial cells and a discontinuous layer of basal cuboidal cells. Underlying this layer was a lamina propia of loose connective tissue containing fibroblasts, fibrous elements, and to a lesser extent, plasma cells, lymphocytes, and macrophages. A pseudostratified columnar epithelium consisting of nonsecretory cells lined the lumen of the papillae. The accompanying lamina propria was thin but highly vascular and included fibroblasts and macrophages. Occupying most of the space between the two mucosae was a smooth muscle layer. Immediately after semen collection capillaries throughout the papillae were dilated and congested with red blood cells (RBCs). Scattered throughout the papillae were extravascular RBCs, suggestive of extensive primary hemorrhage. Although heterophils and macrophages were observed throughout the papillae 24 hr after semen collection, only macrophages were involved in the phagocytosis of extravascular RBCs. Macrophage phagocytic activity was evident at 48 hr and occasionally 72 hr after semen collection. By 72 hr few extravascular RBCs were observed.

Effects of frequency of semen collection on reproductive performance of male turkeys fed low protein diets during the breeder period.

Eight-week-old Large White male turkeys were fed ad libitum a 17% protein corn-soybean meal diet until 28 weeks old. At 28 weeks the average body weight was 14.2 kg and 75% of the males were producing semen. The turkeys were fed diets containing 8, 11, 13, or 17% protein from 28 to 53 weeks. At 53 weeks the average body weights were 17.6, 18.9, 19.0, and 19.2 kg for birds fed 8, 11, 13 and 17% protein, respectively. The turkeys consumed less of the 8 and 11% protein diets: .88 and .92 of the amount of the 17% protein diet consumed during weeks 28 to 53. Semen was collected one time (1x) (Tuesday) and 3x (Monday-Wednesday-Friday) per week from 20 turkeys in each dietary treatment. Semen volume averaged .29 and .21 ml per ejaculate for the 1x/week and 3x/week semen collections, respectively, with no effect of dietary treatment. Sperm concentration (8.28 x 10(9) sperm/ml) was consistent in all groups throughout the experiment. Fertility of eggs set and hatchability of fertile eggs was high (+91%) for hens inseminated with semen collected 1x/week from males fed 8, 11, 13, and 17% protein diets, respectively. However, fertility of semen from the 3x/week semen collection was 79% after the 1st insemination and increased to 92% after the 2nd weekly insemination. Overall fertility for the 10 weeks was 94 and 92% for the 1x/week and 3x/week semen collections, respectively.

Effects of branched and straight chain amines and azasteroids on blood and egg cholesterol of White Leghorn chickens.

Six branched and straight chain secondary or tertiary amines with chain lengths of 12 to 18 carbons and two azasteroids, 25-aza-5 alpha-cholestane and 25-azacoprostane, were fed to mature White Leghorn hens, and their effectiveness was compared with 20,25-diazacholesterol dihydrochloride (SC-12937), an azasteroid known to lower egg cholesterol. Feed consumption, body weight, egg production, egg and plasma cholesterol and desmosterol, and plasma total lipid were measured. The 6 amines were fed at 200 ppm, and only the C12 branched chain amine N,N,3,711-pentamethyldodecanamine reduced plasma and egg cholesterol with a concomitant increase in desmosterol. After 4 weeks, plasma desmosterol was 0, 13, 60, and 75% of total sterol for control, 200 ppm C12 branched chain amine, 5 ppm diazacholesterol, and 5 ppm azacholestane, respectively. Egg production was severely reduced to 6 and 0% by feeding 5 ppm azacholestane for 2 and 4 weeks, respectively, and to 69 and 36% by feeding 5 ppm diazacholesterol. After 4 weeks egg cholesterol was 79 and 36% of the total sterol for the 200 ppm C12 branched chain amine and 5 ppm diazacholesterol, respectively. Concomitant increases in desmosterol accompanied all reductions in cholesterol. The depletion and repletion rates of egg cholesterol were measured in a subsequent experiment. After 2-1/2 weeks of feeding the test substances, egg cholesterol was reduced with concomitant increases in desmosterol. Egg cholesterol was 100, 71, and 50% of the total egg sterol for control, 200 ppm, and 400 ppm C12 branched chain amine, respectively: 58, 13, and 3% for .1, .5, and 1.0 ppm azacholestane; 28, 29, and 18% for 1, 2.5, and 5 ppm azacholesterol; and 23% for 1 ppm azacoprostane. The experimental diets were then withdrawn, and egg cholesterol repletion was studied biweekly. Egg cholesterol was repleted to 100% of the total sterol after withdrawal times of 2 weeks for C12 branched chain amine, 8 weeks for azacoprpostane, 14 to 16 weeks for diazacholesterol, 10 to 16 weeks for the lower levels of azacholestane, and longer than 16 weeks for 1 ppm azacholestane. The increase in desmosterol accompaning the demonstrated reduction in egg cholesterol, particularly with azasteroids, causes one to question the usefulness of this approach to lower cholesterol.