Department of Surgery and OBrtelrics, Facully of Veterinary Medicine, Uniuerdy of Cairo, Gixa
Morphology of epididymal spermatozoa in the ass (Equus asinus) and stallion (Equus caballus) By A.B. ELWISHY] Ms. received 3. 9. 1974
The morphological changes which take place in the sperm during their passage through the excurrent ducts have been studied in the bull (BRANTON and SALISBURY 1947; HANCOCK 1955; BAILYand SMITH1958; AMANNand ALMQUIST 1962; GUSTAFSSON and CRABO 1971 ; RAO1971) and boar (GUSTAFSSON, CRABO and EINARSSON 1970). Such knowledge is of major importance in understanding the origin and significance o f the different sperm abnormalties as well as providing the basis for proper appraisal of semen picture and devising useful spermiograms. The aim of the present work is to study the morphological changes in the sperm o f the ass and stallion during their passage through the epididymis.
Materials and methods Material used in the present study was obtained from 16 stallions and 11 asses of the same age (4-7 years old), with unknown breeding history, which were surgically castrated at the Department of Surgery and Obstetrics, Giza, Arab Republic of Egypt. The animals were clinically sound, the genital organs were normal. Epididyma1 sperm from the caput and corpus were obtained by incising the epididymis with a sharp scalpel at the levels indicated. After applying gentle pressure, epididymal fluid was aspirated with a pasteur pipette and nigrosin-eosin stained smears were prepared (ZEMJANIS 1970). Sperm from the cauda o f the epididymis and the proximal 10 cm of the ductus deferens were collected by aspirating the contents into a pasteur pipette through a small incision and nigrosin-eosin stained smears were prepared after dilution of one drop of the collected semen with two drops of buffered formol saline. Smears prepared from the right and left sides were marked accordingly. Spermatozoon motility at the different levels of the epididymis was assessed at 40" C in samples diluted with 2.9% sodium citrate and 5% glucose solutions. Two hundred sperm were counted in each smear at a magnification of 1000 x and the abnormalities were classified according to BLOM(1972).
1
Present address: Faculty of Veterinary Medicine, Makerere University, P. 0. Box 7062, Kampala, Uganda.
%. Tiienuchrg. Zuchrysbiol. 92 (1975) 67-72
01975 Verlag Paul Parey, Harnliurg und Berlin ISSN 004635811ASTM-Coden: ZTZBAS
68
A.B. ElWisby
Results AS there was no difference between the right and left sides within animals, the results were tabulated irrespective of the side. From the table it could be demonstrated that the ptoportion of sperm with proximal protoplasmic droplets decreased dramatically as the sperm pass from the caput to the corpus epididymides in both the ass and the stallion. In the mean time a clear increase in the incidence of sperm with distal protoplasmic droplets was observed. The transportation of the sperm from the corpus to the cauda, however, was not associated with any appreciable change in the incidence of sperm with distal cytoplasmic droplets, though the decrease in the incidence of sperm with proximal protoplasmic droplets was still obvious. The incidence of proximal and distal cytoplasmic droplets in the sperm collected from the ductus deferens was 3.03 and 41.64% for the ass and 2.62 and 55.19% for the stallion respectively. Although the percentage of live sperm is nearly the same at the different levels studied in both the ass and the stallion, the proportion of motile sperm varies considerably. In most of the samples studied from the caput and corpus epididymides no movement was observed, but occasionally oscillatory movement was noted. In samples collected from the cauda epididymides and ductus deferens the percentage of sperm exhibiting forward movement varies between 10-SO~Oin the ass and 10-40~o in the stallion. Except for free abnormal heads, which increased as the sperm pass through the epididymis, the overall incidence of major sperm abnormalities decreased steadily along the course of the epididymis in both the ass and the stallion. However, the pattern of decrement varies as regards the different types of abnormalities and the level in the epididymis. In the ass, the most prominent decrease in the incidence of sperm heads narrow at the base and small abnormal heads occurred as the sperm pass from the caput to the corpus epididymides. O n the other hand, the decrease in the incidence of pear shaped heads and heads with abnormal contour was more marked as the sperm pass from the body to the tail of the epididymis. For double heads and strongly coiled tails the most appreciable decrease was observed after the spermatozoa had passed from the tail of the epididymis to the ductus deferens. The incidence of souble, thick and swollen middle piece was nearly the same in the different segments of the epididymis as well as in the ductus deferens. In the stallion, the most marked change in the incidence of sperm heads narrow at the base, pear shaped heads, small abnormal heads and double, thickened and swollen middle piece as well as strongly coiled tails occurred as the sperm pass from the caput to the corpus epididymides. However, another prominent decrease in the incidence of sperm with double middle piece occurred as the sperm pass from the tail of the epididymis to the ductus deferens. The incidence of double heads was nearly the same at the different levels studied. As regards minor sperm defects in the ass, a steady increase in the incidence of free normal heads, abaxially implanted middle piece and simply bent or coiled tails was observed in the different segments of the epididymis. On the other hand a clear decrease in the incidence of narrow heads and small normal heads was noted as the sperm pass from the caput to the corpus epididymides. The incidence of giant heads was nearly the same in the different parts of the epididymis. In the stallion, though a steady increase in the incidence of free normal heads, abaxially implanted middle piece, and simply bent or coiled tails as the sperm pass through the epididymis, a steady decrease in the proportion of narrow, small normal and giant heads was observed.
69
Morphology of epididymal sperniatoroa in the ass and Jtallion
Morphology of sperm in samples from epididymis and ductus deferens of the stallion and ass Stallron
Proximal prot. droplets '!(, Distal prot. droplets Live sperm
:(,
(I,)
Motility Major sperm defects
52.36 (12.33) 16.49 (5.34) 68.69 (6.55) Nil t o O.M.
12.26 (3.68) 51.66 (11.44) 75.21 (8.72) Nil t o O.M.
0.78 (1.12) 0.38 (0.35) 1.81 (1.93) 1.19 (0.66) 3.62 (3.11) 0.13 (0.21) 0.35 (0.36) 1.11 (0.86) 0.61 (0.56) 1.54 (1.67) 11.52 (7.21)
0.55 (0.94) 0.21 (0.26) 1.37 (0.96) 0.96 (0.49) 4.06 (3.08) 0.11 (0.19) 0.14 (0.21) 0.88 (0.74) 0.38 (0.41) 1.21 (1.55) 9.87 (5.22)
Ass
2.94 2.62 45.31 (1.44) (1.62) (10.63) 50.08 55.19 12.15 (10.56) (10.58) (8.12) 79.36 74.02 89.38 (9.44) (7.38) (5.64) 1040",, 2040",, Nil t o F.M. F.M. O.M.
8.92 (4.36) 42.11 (14.32) 78.62 (6.41) Nil t o O.M.
1.41 (1.06) 1.29 (1.16) 2.36 (1.41) 2.06 (1.61) 2.26 (2.33) 0.13 (0.31) 0.51 (0.36) 0.40 (0.28) 0.69 (0.56) 2.64 (1.31) 13.75 (6.22)
0.72 (0.47) 1.08 (1.55) 1.oo (0.91) 2.19 (1.88) 3.48 (2.17) 0.1 1 (0.19) 0.44 (0.45) 0.36 (0.25) 0.55 (0.43) 2.36 (0.81) 12.29 (5.49)
4.36 3.03 (3.46) (2.11) 45.21 41.64 (9.61) (11.13) 75.81 74.66 (6.73) (5.92) 10-50*',, 30-50°,, F.M. F.M.
')(,
Ileads narrow at the base Pear shaped heads Small normal heads Abnormal contour Free abnormal heads
Double forms head Middle piece Thick middle piece Swollen middle piece Strongly coiled tail Total major sperm defects
0.61 (0.69) 0.11 (0.19) 1.03 (1.16) 0.75 (0.66) 4.24 (3.91) 0.11 (0.13) 0.14 (0.26) 0.81 (0.69) 0.31 (0.23) 1.16 (0.98) 9.27 (5.66)
0.58 (0.55) 0.11 (0.21) 0.96 (0.84) 0.73 (0.49) 4.61 (3.66) 0.11 (0.21) 0.08 (0.19) 0.74 (0.32) 0.31 (0.28) 1.08 (0.95) 9.31 (4.98)
0.72 (0.58) 0.53 (0.41) 0.34 (0.26) 1.66 (0.98) 3.58 (2.68) 0.11 (0.21) 0.46 (0.38) 0.28 (0.25) 0.58 (0.39) 2.40 (0.98) 10.66 (5.64)
0.41 (0.24) 0.58 (0.64) 0.39 (0.21) 1.12 (0.96) 4.91 (1.43) 0.05 (0.15) 0.41 (0.38) 0.30 (0.25) 0.58 (0.42) 1.96 (0.86) 10.71 (4.81)
Minor sperm defects Narrow heads Small normal heads Giants heads Free normal heads Abaxial implantation Simply bent o r coiled tails
2.63 2.49 1.81 1.36 4.69) 2.58 1.66 1.09 (2.08) (1.17) (1.25) (1.32) (1.23) (0.92) (1.18) (0.91) 2.35 2.00 2.16 1.68 2.16 1.69 1.48 1.69 (2.01) (1.38) (1.66) (1.62) (1.17) (0.99) (0.96) (0.78) 0.18 0.33 0.36 0.31 0.77 0.31 0.18 0.32 (0.62) (0.28) (0.16) (0.21) (0.21) (0.20) (0.22) (0.24) 2.64 3.32 4.11 7.94 2.86 4.86 4.58 (1.79) (2.64) (3.91) (4.26) (1.63) (2.34) (3.52) 2.30 2.30 47.92 69.41 84.18 0.34 1.48 (0.28) (1.21) (2.11) (1.13) (8.30) (10.10) (9.40) 4.11 6.64 6.66 9.58 6.91 8.68 8.19 (2.14) (3.66) (4.32) (4.63) (4.23) (4.31) (7.36)
Figures in parentheses represent the standard deviation. F.M. = Forward movement.
-
0.M.
5.84 (2.71) 77.40 (7.31) 11.24 (5.81)
Oscillatory movement,
:
70
A.B. EWisby
Discussion The results reported herein showed that the percentage of live sperm is nearly the same in the different portions of the epididymis as well as in the ductus deferens which agreed with the findings of IGBOELI and FOOTE (1968) in bulls. Although IGBOELLI and FOOTE(1968) reported that spermatozoa collected from the caput epididymides of bulls were immotile, occasional motile sperm were seen in samples from two out of 40 caput epididymides examined by AMANN and ALMQUIST (1962). The latter finding supports the present observations of oscillatory movement displayed in some of the samples collected from the caput epididymides of the ass and the stallion. The low percentage of motile sperm in the corpus and cauda epididymides of the ass and stallion agreed with the findings of AMANN and ALMQUIST (1962) in bulls. In accordance with previous observation in bulls the proportion of sperm with proximal cytoplasmic droplets decreased as the sperm pass through epididymides of the ass and stallion. However, discrepancies in the relative distribution values for proximal and distal cytoplasmic droplets in the various segments of the epididymis in this study and those by BRANTON and SALISBURY (1947), BAILYand SMITH(1958), AMANN and ALMQUIST (1962), GUSTAFSSON and CRABO (1971) and RAO(1971) in bulls could be due to technique and sampling differences. SELIVANOVA (1937), GUSTAFSSON and CRABO(1971) and RAO (1971) found that in two different parts of the caput epididymides of the bull the relative distribution of sperm with proximal and distal cytoplasmic droplets varied. Also, CAMPBELL, HANCOCK and SHAW(1960) reported a significantly lower frequency of cytoplasmic droplets, both proximal and distal, in nigrosin-eosin stained smears than in fixed wet preparations. The incidence of sperm defects for stallions of normal reproductive capacity as reported in the relevant literature was widely different. The average values of 24, 16, 18.2 and 17-25 were given by BIELANSKI (1951), NISHIKAWA, WAIDEand ONUMA (1951a), SZUMOWSKI (1964) and HENDRIKES (1966) respectively. The incidence of sperm abnormalities in the semen of the ass averaged 14.3 (NISHIKAWA, WAIDEand ONUMA, 1951b). However, these figures are not directly comparable with the present results because of the nature of the material examined and the basis on which different abnormalities were sorted. In accordance with the results of AMANN and ALMQUIST (1962) and RAO(1971) in bulls the overall incidence of abnormal sperm heads in the ass and stallion, whether these were major or minor defects, decreased as the sperm pass down the epididymis. However, the pattern of decrease varied as regards the different abnormalities and zones of the epididymis. This could be due to regional differences in the morphology, physiology and metabolism of the epididymis as well as variation in the rate of resorption or dissolution of the different types of abnormalities (RAO 1971). The latter author stated that owing to weakly bound nuclear proteins certains types of abnormal forms undergo resorption or dissolution more readily than other types. The same phenomena might also apply to the decrease in the incidence of double and defective middle pieces in the stallion. Exceptional to sperm head abnormalities are tailless heads, both normal and pathological, which increased as the sperm pass through the epididymis. This agreed with the findings of GUSTAFSSON and CRABO (1971) in bulls. Activation and motility of the sperm as they pass from the caput to the other regions might advance an explanation. However, the significance of this findings as being indication of incipient sperm degeneration (GLOVER 1962) cannot be excluded.
Morphology of epididymal spermatoxoa in the ass and sfallion
71
The increase in the incidence of simply bent or coiled tails in the consequative segments of the epididymides, agreed with the findings o f GUSTAFSSON et al. (1970) in boars and GUSTAFSSON and CRABO (1971) in bulls. Although RAO(1971) stated that changes in the environment (osmotic pressure, ion concentration, metabolic changes) during passage through the genital tract, together with low vitality and resistance o f some sperm might be the possible causes of this phenomenon, GLOVER (1958) however, found that degeneration of the rabbit sperm was characterised by increased incidence of coiled tails. A striking observation in this study is the very high incidence of abaxially attached middle piece in the sperm of the ass. Although the same observation was previously reported for an infertile ass stallion (TRABALLESI, CAPURSO and AMENDOLA 1963), it was a consistant feature in all asses examined in the current study, for which no information is available as regards fertility and reproductive performance. The increase in the incidence of such deformity as the sperm pass through the epididymis in the ass and to a much less clear extent in the stallion, might verify its epididymal origin. Nevertheless, further and more detailed studies on this point are needed. Summary The morphology of epididymal sperm of 16 stallions and 11 asses was studied. The incidence of major sperm defects, except for tailless abnormal heads, decreased as the sperm pass through the epididymis. On the other hand minor sperm defects increased as the sperm pass down the epididymis. The most striking observation in this study was the high indidence of abaxially implanted middle piece in the ass. The incidence of this defect increases as the sperm pass through the epididymis.
Zusammenfassung Morphologie der Nebenhodenspermien bei Ereln (Equus asinus) und Pfirdeti (Equus caballus) Die Morphologie der Nebenhodenspermien von 16 Pferde- und 11 Eselhengsten wurde untersucht. Das Auftreten der groReren Defekte, mit Ausnahme der schwanzlosen, abnormalen Kopfe, nahm nach der Passage durch den Nebenhodengang ab. Andererseits nahmcn geringere Spermiendefekte heim Durchgang durch die Epididymis zu. Die auffalligste Beobachtung dieser Untersuchung war das haufige Auftreten yon exzentrisch implantierten Mittelstticken beim Eselhengst. Die Haufigkeit dieser Erscheinung nimmt zu, wenn die Spermien durch den Nebenhodengang gewandert sind.
References AMANN, R.P.; ALMQUIST, J.O., 1962: Reproductive capacity of dairy bulls. VlII. Morphology of epididymal spermatozoa. J. Dairy Sci. 55, 1516. BAILY,G.; SMITH, V.R., 1958: Influence of seminal vesicular fluid on morphology of bull spermatozoa. J Dairy Sci. 41, 422. BEIIANSKI, W., 1951: Characteristics of the semen of stallions. Macro and microscopic investigations with estimation of fertility. Mem. Acad. Polon. Sci. Lettr., CI. Sci., math. nat. B, 59 pp. (Anim. h e e d . Abstr. 19, 429). BLOM,E., 1972: The ultrastructure of some characteristic sperm defects and a proposal for a new classification of the bull spermiogram. Atti. Del. VII Simposio Internazionale D I Zootecnia pp. 125. BRANTON, C.; SALISBURY, G.W., 1947: Morphology of spermatozoa from different levels of the reproductive tract of the bull. J. Anim. Sci. 6, 154. CAMPBELL, R.C.; HANCOCK, J.L.; SHAW,I.G., 1960: Cytological characteristics and fertilizing capacity of bull spermatozoa. J. Agtic. Sci., Camb. 55, 91. GLOVER, T.D., 1958: Experimental Induction of Seminal Degeneration in rabbits. Proc. SOC.Study Fertility 10, 80. -1962: The response of rabbit spermatozoa to artificial cryptorchidism and ligation of the epididymis. J. Endocrinology 23, 317. GUSTAFSSON, B. ; CRABO, B., 1971: Some morphological characteristics o f bull spermatozoa at different levels of the epididymis Nord. Vet. Med. 23, 114. -- EINARSSON, S., 1970: Morphology of the spermatozoa and composition of the plasma in the boar epididymis. Proc. 11th Nordisk Vet. Congress, pp. 241. HANCOCK, J.L., 1955: The disintegration of bull spermatozoa. Vet. Rec. 67, 825.
72
A . B . EIWisby
HENDRIKES, J., 1966: The semen of stallion of normal fertility. Tijdschr. Diergeneesk. 91,300 (Anim. Breed. Abstr. 34,326). IGBOELI, G.; FOOTE, R.H., 1968: Maturation changes in bull epididymal spermatozoa, J. Dairy Sci. 51, 1703. NISHIKAWA, Y.; WAIDE,Y.; ONKJMA, H., 1951a: Studies on artificial insemination in the horse. VI Morphological studies on horse spermatozoa. Bull Nat. Inst. Agric. Sci. (Chiba), Ser. G, No. 1, 29 (Anim. Breed. Abstr. 20, 15). - _ _ 1951 b : Studies on reproduction in asses. VI1 Morphological studies of semen. Bull Nat. Inst. Agric. Sci. (Chiba), Srn. G., No. 1, 47 (Anim. Breed. Abstr. 20, 15). RAO,A.R., 1971: Changes in the morphology of sperm during their passage through the genital tract in bulls with normal and impaired spermatogenesis. Thesis, Stockholm. SELIVANOVA, 0.A., 1937: The movement and disappearance of the Kinoplasmic droplet in spermatozoa of farm animals. A contribution to the question of maturity of spermatozoa. Usp. Zooteh. Nauk. 4, 67 (Anim. Breed. Abstr. 7, 180). SZUMOWSKI, P., 1964: Testing the reproductive faculties of the stallion. C.R. Acad. Agric. Fr. 50, 697 (Anim. Breed. Abstr. 33, 193). TRABALLESI, B.; CAPURSO, A.; AMENDOLA, G., 1963: Sperm malfarmation causing sterility in the ass stallion. Atti SOC.Ital. Sci. Vet. 16, 196 (Anim. Breed. Abstr. 32, 140). ZEMJANIS, R., 1970: Diagnostic and Therapeutic Techniques in Animal Reproduction. Baltimore: The Williams and Wilkins Co., pp. 155, 188. Author's address: Dr. A.B. ELWISHY, Department of Surgery and Obstetrics, Faculty of Veterinary Medicine, University of Cairo, Giza, Egypt
Morphology of epididymal spermatozoa in the ass (Equus asinus) and stallion (Equus caballus) By A.B. ELWISHY] Ms. received 3. 9. 1974
The morphological changes which take place in the sperm during their passage through the excurrent ducts have been studied in the bull (BRANTON and SALISBURY 1947; HANCOCK 1955; BAILYand SMITH1958; AMANNand ALMQUIST 1962; GUSTAFSSON and CRABO 1971 ; RAO1971) and boar (GUSTAFSSON, CRABO and EINARSSON 1970). Such knowledge is of major importance in understanding the origin and significance o f the different sperm abnormalties as well as providing the basis for proper appraisal of semen picture and devising useful spermiograms. The aim of the present work is to study the morphological changes in the sperm o f the ass and stallion during their passage through the epididymis.
Materials and methods Material used in the present study was obtained from 16 stallions and 11 asses of the same age (4-7 years old), with unknown breeding history, which were surgically castrated at the Department of Surgery and Obstetrics, Giza, Arab Republic of Egypt. The animals were clinically sound, the genital organs were normal. Epididyma1 sperm from the caput and corpus were obtained by incising the epididymis with a sharp scalpel at the levels indicated. After applying gentle pressure, epididymal fluid was aspirated with a pasteur pipette and nigrosin-eosin stained smears were prepared (ZEMJANIS 1970). Sperm from the cauda o f the epididymis and the proximal 10 cm of the ductus deferens were collected by aspirating the contents into a pasteur pipette through a small incision and nigrosin-eosin stained smears were prepared after dilution of one drop of the collected semen with two drops of buffered formol saline. Smears prepared from the right and left sides were marked accordingly. Spermatozoon motility at the different levels of the epididymis was assessed at 40" C in samples diluted with 2.9% sodium citrate and 5% glucose solutions. Two hundred sperm were counted in each smear at a magnification of 1000 x and the abnormalities were classified according to BLOM(1972).
1
Present address: Faculty of Veterinary Medicine, Makerere University, P. 0. Box 7062, Kampala, Uganda.
%. Tiienuchrg. Zuchrysbiol. 92 (1975) 67-72
01975 Verlag Paul Parey, Harnliurg und Berlin ISSN 004635811ASTM-Coden: ZTZBAS
68
A.B. ElWisby
Results AS there was no difference between the right and left sides within animals, the results were tabulated irrespective of the side. From the table it could be demonstrated that the ptoportion of sperm with proximal protoplasmic droplets decreased dramatically as the sperm pass from the caput to the corpus epididymides in both the ass and the stallion. In the mean time a clear increase in the incidence of sperm with distal protoplasmic droplets was observed. The transportation of the sperm from the corpus to the cauda, however, was not associated with any appreciable change in the incidence of sperm with distal cytoplasmic droplets, though the decrease in the incidence of sperm with proximal protoplasmic droplets was still obvious. The incidence of proximal and distal cytoplasmic droplets in the sperm collected from the ductus deferens was 3.03 and 41.64% for the ass and 2.62 and 55.19% for the stallion respectively. Although the percentage of live sperm is nearly the same at the different levels studied in both the ass and the stallion, the proportion of motile sperm varies considerably. In most of the samples studied from the caput and corpus epididymides no movement was observed, but occasionally oscillatory movement was noted. In samples collected from the cauda epididymides and ductus deferens the percentage of sperm exhibiting forward movement varies between 10-SO~Oin the ass and 10-40~o in the stallion. Except for free abnormal heads, which increased as the sperm pass through the epididymis, the overall incidence of major sperm abnormalities decreased steadily along the course of the epididymis in both the ass and the stallion. However, the pattern of decrement varies as regards the different types of abnormalities and the level in the epididymis. In the ass, the most prominent decrease in the incidence of sperm heads narrow at the base and small abnormal heads occurred as the sperm pass from the caput to the corpus epididymides. O n the other hand, the decrease in the incidence of pear shaped heads and heads with abnormal contour was more marked as the sperm pass from the body to the tail of the epididymis. For double heads and strongly coiled tails the most appreciable decrease was observed after the spermatozoa had passed from the tail of the epididymis to the ductus deferens. The incidence of souble, thick and swollen middle piece was nearly the same in the different segments of the epididymis as well as in the ductus deferens. In the stallion, the most marked change in the incidence of sperm heads narrow at the base, pear shaped heads, small abnormal heads and double, thickened and swollen middle piece as well as strongly coiled tails occurred as the sperm pass from the caput to the corpus epididymides. However, another prominent decrease in the incidence of sperm with double middle piece occurred as the sperm pass from the tail of the epididymis to the ductus deferens. The incidence of double heads was nearly the same at the different levels studied. As regards minor sperm defects in the ass, a steady increase in the incidence of free normal heads, abaxially implanted middle piece and simply bent or coiled tails was observed in the different segments of the epididymis. On the other hand a clear decrease in the incidence of narrow heads and small normal heads was noted as the sperm pass from the caput to the corpus epididymides. The incidence of giant heads was nearly the same in the different parts of the epididymis. In the stallion, though a steady increase in the incidence of free normal heads, abaxially implanted middle piece, and simply bent or coiled tails as the sperm pass through the epididymis, a steady decrease in the proportion of narrow, small normal and giant heads was observed.
69
Morphology of epididymal sperniatoroa in the ass and Jtallion
Morphology of sperm in samples from epididymis and ductus deferens of the stallion and ass Stallron
Proximal prot. droplets '!(, Distal prot. droplets Live sperm
:(,
(I,)
Motility Major sperm defects
52.36 (12.33) 16.49 (5.34) 68.69 (6.55) Nil t o O.M.
12.26 (3.68) 51.66 (11.44) 75.21 (8.72) Nil t o O.M.
0.78 (1.12) 0.38 (0.35) 1.81 (1.93) 1.19 (0.66) 3.62 (3.11) 0.13 (0.21) 0.35 (0.36) 1.11 (0.86) 0.61 (0.56) 1.54 (1.67) 11.52 (7.21)
0.55 (0.94) 0.21 (0.26) 1.37 (0.96) 0.96 (0.49) 4.06 (3.08) 0.11 (0.19) 0.14 (0.21) 0.88 (0.74) 0.38 (0.41) 1.21 (1.55) 9.87 (5.22)
Ass
2.94 2.62 45.31 (1.44) (1.62) (10.63) 50.08 55.19 12.15 (10.56) (10.58) (8.12) 79.36 74.02 89.38 (9.44) (7.38) (5.64) 1040",, 2040",, Nil t o F.M. F.M. O.M.
8.92 (4.36) 42.11 (14.32) 78.62 (6.41) Nil t o O.M.
1.41 (1.06) 1.29 (1.16) 2.36 (1.41) 2.06 (1.61) 2.26 (2.33) 0.13 (0.31) 0.51 (0.36) 0.40 (0.28) 0.69 (0.56) 2.64 (1.31) 13.75 (6.22)
0.72 (0.47) 1.08 (1.55) 1.oo (0.91) 2.19 (1.88) 3.48 (2.17) 0.1 1 (0.19) 0.44 (0.45) 0.36 (0.25) 0.55 (0.43) 2.36 (0.81) 12.29 (5.49)
4.36 3.03 (3.46) (2.11) 45.21 41.64 (9.61) (11.13) 75.81 74.66 (6.73) (5.92) 10-50*',, 30-50°,, F.M. F.M.
')(,
Ileads narrow at the base Pear shaped heads Small normal heads Abnormal contour Free abnormal heads
Double forms head Middle piece Thick middle piece Swollen middle piece Strongly coiled tail Total major sperm defects
0.61 (0.69) 0.11 (0.19) 1.03 (1.16) 0.75 (0.66) 4.24 (3.91) 0.11 (0.13) 0.14 (0.26) 0.81 (0.69) 0.31 (0.23) 1.16 (0.98) 9.27 (5.66)
0.58 (0.55) 0.11 (0.21) 0.96 (0.84) 0.73 (0.49) 4.61 (3.66) 0.11 (0.21) 0.08 (0.19) 0.74 (0.32) 0.31 (0.28) 1.08 (0.95) 9.31 (4.98)
0.72 (0.58) 0.53 (0.41) 0.34 (0.26) 1.66 (0.98) 3.58 (2.68) 0.11 (0.21) 0.46 (0.38) 0.28 (0.25) 0.58 (0.39) 2.40 (0.98) 10.66 (5.64)
0.41 (0.24) 0.58 (0.64) 0.39 (0.21) 1.12 (0.96) 4.91 (1.43) 0.05 (0.15) 0.41 (0.38) 0.30 (0.25) 0.58 (0.42) 1.96 (0.86) 10.71 (4.81)
Minor sperm defects Narrow heads Small normal heads Giants heads Free normal heads Abaxial implantation Simply bent o r coiled tails
2.63 2.49 1.81 1.36 4.69) 2.58 1.66 1.09 (2.08) (1.17) (1.25) (1.32) (1.23) (0.92) (1.18) (0.91) 2.35 2.00 2.16 1.68 2.16 1.69 1.48 1.69 (2.01) (1.38) (1.66) (1.62) (1.17) (0.99) (0.96) (0.78) 0.18 0.33 0.36 0.31 0.77 0.31 0.18 0.32 (0.62) (0.28) (0.16) (0.21) (0.21) (0.20) (0.22) (0.24) 2.64 3.32 4.11 7.94 2.86 4.86 4.58 (1.79) (2.64) (3.91) (4.26) (1.63) (2.34) (3.52) 2.30 2.30 47.92 69.41 84.18 0.34 1.48 (0.28) (1.21) (2.11) (1.13) (8.30) (10.10) (9.40) 4.11 6.64 6.66 9.58 6.91 8.68 8.19 (2.14) (3.66) (4.32) (4.63) (4.23) (4.31) (7.36)
Figures in parentheses represent the standard deviation. F.M. = Forward movement.
-
0.M.
5.84 (2.71) 77.40 (7.31) 11.24 (5.81)
Oscillatory movement,
:
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Discussion The results reported herein showed that the percentage of live sperm is nearly the same in the different portions of the epididymis as well as in the ductus deferens which agreed with the findings of IGBOELI and FOOTE (1968) in bulls. Although IGBOELLI and FOOTE(1968) reported that spermatozoa collected from the caput epididymides of bulls were immotile, occasional motile sperm were seen in samples from two out of 40 caput epididymides examined by AMANN and ALMQUIST (1962). The latter finding supports the present observations of oscillatory movement displayed in some of the samples collected from the caput epididymides of the ass and the stallion. The low percentage of motile sperm in the corpus and cauda epididymides of the ass and stallion agreed with the findings of AMANN and ALMQUIST (1962) in bulls. In accordance with previous observation in bulls the proportion of sperm with proximal cytoplasmic droplets decreased as the sperm pass through epididymides of the ass and stallion. However, discrepancies in the relative distribution values for proximal and distal cytoplasmic droplets in the various segments of the epididymis in this study and those by BRANTON and SALISBURY (1947), BAILYand SMITH(1958), AMANN and ALMQUIST (1962), GUSTAFSSON and CRABO (1971) and RAO(1971) in bulls could be due to technique and sampling differences. SELIVANOVA (1937), GUSTAFSSON and CRABO(1971) and RAO (1971) found that in two different parts of the caput epididymides of the bull the relative distribution of sperm with proximal and distal cytoplasmic droplets varied. Also, CAMPBELL, HANCOCK and SHAW(1960) reported a significantly lower frequency of cytoplasmic droplets, both proximal and distal, in nigrosin-eosin stained smears than in fixed wet preparations. The incidence of sperm defects for stallions of normal reproductive capacity as reported in the relevant literature was widely different. The average values of 24, 16, 18.2 and 17-25 were given by BIELANSKI (1951), NISHIKAWA, WAIDEand ONUMA (1951a), SZUMOWSKI (1964) and HENDRIKES (1966) respectively. The incidence of sperm abnormalities in the semen of the ass averaged 14.3 (NISHIKAWA, WAIDEand ONUMA, 1951b). However, these figures are not directly comparable with the present results because of the nature of the material examined and the basis on which different abnormalities were sorted. In accordance with the results of AMANN and ALMQUIST (1962) and RAO(1971) in bulls the overall incidence of abnormal sperm heads in the ass and stallion, whether these were major or minor defects, decreased as the sperm pass down the epididymis. However, the pattern of decrease varied as regards the different abnormalities and zones of the epididymis. This could be due to regional differences in the morphology, physiology and metabolism of the epididymis as well as variation in the rate of resorption or dissolution of the different types of abnormalities (RAO 1971). The latter author stated that owing to weakly bound nuclear proteins certains types of abnormal forms undergo resorption or dissolution more readily than other types. The same phenomena might also apply to the decrease in the incidence of double and defective middle pieces in the stallion. Exceptional to sperm head abnormalities are tailless heads, both normal and pathological, which increased as the sperm pass through the epididymis. This agreed with the findings of GUSTAFSSON and CRABO (1971) in bulls. Activation and motility of the sperm as they pass from the caput to the other regions might advance an explanation. However, the significance of this findings as being indication of incipient sperm degeneration (GLOVER 1962) cannot be excluded.
Morphology of epididymal spermatoxoa in the ass and sfallion
71
The increase in the incidence of simply bent or coiled tails in the consequative segments of the epididymides, agreed with the findings o f GUSTAFSSON et al. (1970) in boars and GUSTAFSSON and CRABO (1971) in bulls. Although RAO(1971) stated that changes in the environment (osmotic pressure, ion concentration, metabolic changes) during passage through the genital tract, together with low vitality and resistance o f some sperm might be the possible causes of this phenomenon, GLOVER (1958) however, found that degeneration of the rabbit sperm was characterised by increased incidence of coiled tails. A striking observation in this study is the very high incidence of abaxially attached middle piece in the sperm of the ass. Although the same observation was previously reported for an infertile ass stallion (TRABALLESI, CAPURSO and AMENDOLA 1963), it was a consistant feature in all asses examined in the current study, for which no information is available as regards fertility and reproductive performance. The increase in the incidence of such deformity as the sperm pass through the epididymis in the ass and to a much less clear extent in the stallion, might verify its epididymal origin. Nevertheless, further and more detailed studies on this point are needed. Summary The morphology of epididymal sperm of 16 stallions and 11 asses was studied. The incidence of major sperm defects, except for tailless abnormal heads, decreased as the sperm pass through the epididymis. On the other hand minor sperm defects increased as the sperm pass down the epididymis. The most striking observation in this study was the high indidence of abaxially implanted middle piece in the ass. The incidence of this defect increases as the sperm pass through the epididymis.
Zusammenfassung Morphologie der Nebenhodenspermien bei Ereln (Equus asinus) und Pfirdeti (Equus caballus) Die Morphologie der Nebenhodenspermien von 16 Pferde- und 11 Eselhengsten wurde untersucht. Das Auftreten der groReren Defekte, mit Ausnahme der schwanzlosen, abnormalen Kopfe, nahm nach der Passage durch den Nebenhodengang ab. Andererseits nahmcn geringere Spermiendefekte heim Durchgang durch die Epididymis zu. Die auffalligste Beobachtung dieser Untersuchung war das haufige Auftreten yon exzentrisch implantierten Mittelstticken beim Eselhengst. Die Haufigkeit dieser Erscheinung nimmt zu, wenn die Spermien durch den Nebenhodengang gewandert sind.
References AMANN, R.P.; ALMQUIST, J.O., 1962: Reproductive capacity of dairy bulls. VlII. Morphology of epididymal spermatozoa. J. Dairy Sci. 55, 1516. BAILY,G.; SMITH, V.R., 1958: Influence of seminal vesicular fluid on morphology of bull spermatozoa. J Dairy Sci. 41, 422. BEIIANSKI, W., 1951: Characteristics of the semen of stallions. Macro and microscopic investigations with estimation of fertility. Mem. Acad. Polon. Sci. Lettr., CI. Sci., math. nat. B, 59 pp. (Anim. h e e d . Abstr. 19, 429). BLOM,E., 1972: The ultrastructure of some characteristic sperm defects and a proposal for a new classification of the bull spermiogram. Atti. Del. VII Simposio Internazionale D I Zootecnia pp. 125. BRANTON, C.; SALISBURY, G.W., 1947: Morphology of spermatozoa from different levels of the reproductive tract of the bull. J. Anim. Sci. 6, 154. CAMPBELL, R.C.; HANCOCK, J.L.; SHAW,I.G., 1960: Cytological characteristics and fertilizing capacity of bull spermatozoa. J. Agtic. Sci., Camb. 55, 91. GLOVER, T.D., 1958: Experimental Induction of Seminal Degeneration in rabbits. Proc. SOC.Study Fertility 10, 80. -1962: The response of rabbit spermatozoa to artificial cryptorchidism and ligation of the epididymis. J. Endocrinology 23, 317. GUSTAFSSON, B. ; CRABO, B., 1971: Some morphological characteristics o f bull spermatozoa at different levels of the epididymis Nord. Vet. Med. 23, 114. -- EINARSSON, S., 1970: Morphology of the spermatozoa and composition of the plasma in the boar epididymis. Proc. 11th Nordisk Vet. Congress, pp. 241. HANCOCK, J.L., 1955: The disintegration of bull spermatozoa. Vet. Rec. 67, 825.
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HENDRIKES, J., 1966: The semen of stallion of normal fertility. Tijdschr. Diergeneesk. 91,300 (Anim. Breed. Abstr. 34,326). IGBOELI, G.; FOOTE, R.H., 1968: Maturation changes in bull epididymal spermatozoa, J. Dairy Sci. 51, 1703. NISHIKAWA, Y.; WAIDE,Y.; ONKJMA, H., 1951a: Studies on artificial insemination in the horse. VI Morphological studies on horse spermatozoa. Bull Nat. Inst. Agric. Sci. (Chiba), Ser. G, No. 1, 29 (Anim. Breed. Abstr. 20, 15). - _ _ 1951 b : Studies on reproduction in asses. VI1 Morphological studies of semen. Bull Nat. Inst. Agric. Sci. (Chiba), Srn. G., No. 1, 47 (Anim. Breed. Abstr. 20, 15). RAO,A.R., 1971: Changes in the morphology of sperm during their passage through the genital tract in bulls with normal and impaired spermatogenesis. Thesis, Stockholm. SELIVANOVA, 0.A., 1937: The movement and disappearance of the Kinoplasmic droplet in spermatozoa of farm animals. A contribution to the question of maturity of spermatozoa. Usp. Zooteh. Nauk. 4, 67 (Anim. Breed. Abstr. 7, 180). SZUMOWSKI, P., 1964: Testing the reproductive faculties of the stallion. C.R. Acad. Agric. Fr. 50, 697 (Anim. Breed. Abstr. 33, 193). TRABALLESI, B.; CAPURSO, A.; AMENDOLA, G., 1963: Sperm malfarmation causing sterility in the ass stallion. Atti SOC.Ital. Sci. Vet. 16, 196 (Anim. Breed. Abstr. 32, 140). ZEMJANIS, R., 1970: Diagnostic and Therapeutic Techniques in Animal Reproduction. Baltimore: The Williams and Wilkins Co., pp. 155, 188. Author's address: Dr. A.B. ELWISHY, Department of Surgery and Obstetrics, Faculty of Veterinary Medicine, University of Cairo, Giza, Egypt
