Printer Friendly

Testicular biopsy in psittacine birds (Psittaciformes): impact of endoscopy and biopsy on health, testicular morphology, and sperm parameters.

Abstract: Histologic examination of a testicular biopsy sample may be required to evaluate the reproductive status of male psittacine birds. The purpose of this study was to evaluate the viability of testicular sampling from live birds by assessing the impact on the birds' health, testicular integrity, and sperm quality. Testicular biopsy samples were obtained by endoscopy 4 times during 12 months from 9 cockatiels (Nymphicus hollandicus) and 7 rose-ringed parakeets (Psittacula krameri). Only 2 of 16 birds showed testicular cicatrization or divided testicular tissue after a single endoscopy. Further complications, such as damage to the air sacs or bleeding, predominantly occurred in subsequent endoscopies. In both species, endoscopy and testicular biopsy caused only minor or transient effects on sperm production and sperm quality. These results support that a single testicular biopsy is a viable method for evaluating the reproductive status of male psittacine birds.

Key words: testicular biopsy, endoscopy, sperm, avian, cockatiels, parakeets, Psittaciformes, Nymphicus hollandicus, Psittacula krameri

Introduction

One of the most threatened bird orders worldwide is Psittaciformes, the parrots. (1) Hence, intense research concerning reproductive physiology of these birds is required. Several approaches are available for assessing the reproductive status of male psittacine birds, predominantly sperm analysis (2-11) or endoscopic evaluation of testicular morphology. (12) However, results of part 1 of this study ("Testicular biopsy in psittacine birds [Psittaciformes]: Comparative evaluation of testicular reproductive status by endoscopic, histologic, and cytologic examination") revealed that macroscopic evaluation of the testicles in different psittacine birds is unreliable and that histologic investigation of a testicular biopsy sample is required. (13) Several studies have evaluated testicular histology in different psittacine birds but mainly via intravitam or postmortem removal of testicles. (14-18) The purpose of the present study was to evaluate the viability of testicular sampling from live birds by assessing the impact on the birds' health, testicular integrity, and sperm quality.

Materials and Methods

Birds

The study period was November 2006 through December 2007. During this time, 7 male rose-ringed parakeets (Psittacula krameri; 3-7 years old; mean age, 5 years) housed with 3 female parakeets and 9 male cockatiels (Nymphicus hollandicus; 2-5 years old, mean age, 4 years) housed with 2 females were kept in aviaries. Husbandry conditions were given in part 1 of this paper. (13) Briefly, the birds were kept in outdoor aviaries from April to October and in outdoor aviaries during the cold season.

Endoscopy and testicular sampling

A total of 4 endoscopic procedures were performed in each bird at 3-month intervals. Endoscopies were carried out in January, April, July, and October as previously describedy. (13) First, the appearance of the testicular surface and the air sac membranes were evaluated to document pathologic alterations arising from recent endoscopies. A biopsy sample was taken from the cranial part of the left testicle, away from the epididymis, by biopsy forceps measuring 1.7 mm (5 Fr, Karl Storz, Tuttlingen, Germany). When removing the biopsy forceps from the body cavity, counterpressure with the working channel was exerted on the testicle to avoid lacerating the testicular vessels. Any occurrence of apnea, hemorrhage, early termination of endoscopy, intraoperative or postoperative death, or prolonged recovery after anesthesia was documented.

Spermatologic examination

From late February 2007 until December 2007, desemination trials were performed in all males once a week. Semen collection was performed in the morning, according to the established method of cloacal massage in budgerigars (Melopsittacus undulatus). (4,7) Because rose-ringed parakeets and cockatiels are larger and more resolute than budgerigars, an assistant loosely restrained the bird in a half upright position. The cloaca was massaged with the index and middle finger of the right hand, until an active ejaculation occurred or sperm was collected passively due to cloacal pressure. The obtained seminal fluid was collected immediately in a calibrated microcapillary tube (Ringcaps 1-5 [micro]L, Hirschmann Laborgerate GmbH & Co KG, Eberstadt, Germany) held in the left hand of the examiner. Cloacal massage was discontinued in cases in which birds displayed defensive behavior, such as intense struggling or screaming, or if cloacal bleeding occurred. Generally, the massage was stopped after about 10 minutes if sexual excitation of the bird ceased.

The collected semen samples were examined macroscopically and microscopically. Volume, color, consistency, impurities (blood, urine, feces), and pH of the semen samples, as well as motility of spermatozoa, sperm concentration and total sperm count, live-dead ratio, and pathologic changes of spermatozoal morphology, were assessed as described previously in budgerigars. (10)

Statistical analysis

To evaluate the influence of endoscopy on sperm parameters, the sperm parameters were assessed in intervals of approximately 4 weeks, representing monthly intervals. The postendoscopic interval was only 3 weeks because spermatogenesis in birds lasts up to 3 weeks, including time of passage through the epididymis and ductus deferens. (19,20) Sperm parameters from semen samples obtained within the postendoscopic interval were then compared with those from the samples obtained in the pre-endoscopic interval.

Statistical analysis was conducted by using SigmaPlot 11.0 (Systat Software GmbH, Erkrath, Germany). The Shapiro-Wilk test was used to test normal or non-normal distribution of all data. Significant differences were tested by using the t test (parametrically) or Mann-Whitney U test (nonparametrically). Results were considered significant at P < .05.

Results

Impact of anesthesia and surgery on the health status of the birds

No complications arising from anesthesia, such as apnea, occurred in 64 endoscopic procedures. Among these, 59 surgeries proceeded without complications, and the birds recovered from anesthesia within a few minutes. In the remaining 5 surgical procedures, internal hemorrhage occurred intraoperatively, leading to discontinuation of the endoscopy. Four of these birds recovered quickly and without complications from anesthesia. One rose-ringed parakeet died immediately after endoscopy. Internal bleeding occurred in April, July, and October during culmination in the cockatiels (n = 3) and during quiescence in the rose-ringed parakeets (n = 2).

Impact of testicular biopsy on testicular morphology

No pre-existing defects were seen on the testicles or air sacs during the first endoscopy. Three months later, more than 80% of the cockatiels (8/9) and rose-ringed parakeets (6/7) had no macroscopically visible sequelae resulting from the first endoscopy. Only 1 cockatiel displayed divided testicular tissue (fissured and gaping testicular tissue), and 1 rose-ringed parakeet had testicular cicatrization (scars) at this time. The number of birds with damaged testicles or air sacs, mainly in the form of testicular cicatrization, increased in the subsequent endoscopies (Fig 1). Further macroscopic changes were division of testicular tissue and thickened air sac membranes. In 1 cockatiel, the left testicle was absent at the fourth endoscopy. Above all, 3 of 9 cockatiels and 6 of 7 rose-ringed parakeets showed pathologic findings in the left testicle at the fourth endoscopy. The remaining birds either developed persistent air sac holes or showed no pathologic changes. In 1 case, evaluation was not possible due to early termination of the endoscopy arising from hemorrhage.

Impact of testicular biopsy on sperm production and quality

In the rose-ringed parakeets, semen collection was inconsistent. Only 9 sperm samples were collected from 3 birds. Semen collection was successful in March and in May but completely failed in April. Statistical evaluation of sperm parameters based on the impact of endoscopy was not performed due to the small number of semen samples.

By contrast, semen collection was consistently successful in the cockatiels. The number of semen samples collected each week increased in April and May (Fig 2) because the birds were kept in an outdoor aviary. However, the proportion of passive ejaculations increased predominantly, whereas active ejaculations decreased during the course of the year. Although sperm production of the cockatiels declined in September and October, there was a brief upward trend in November, after the birds were moved back into the indoor aviary. The impact of endoscopy was initially evaluated after the second endoscopy performed in April. This endoscopic procedure had no significant effects on sperm production (Fig 2) and sperm quality (Fig 3). In July, sperm concentration, total sperm count (P < .001), and live-dead ratio of spermatozoa (P < .02) were significantly lower after endoscopy than in the weeks before. Those values did not change in the following months but increased again in early October. Further sperm parameters displayed no alteration after endoscopy. The last endoscopic procedure was performed in late October. At this time, because the testicles were regressing in many cockatiels and sperm quality was low, the procedure had no effect on sperm production and sperm parameters.

Discussion

A single endoscopic testicular biopsy caused no complications in most of the examined cockatiels and rose-ringed parakeets, analogous to the results in budgerigars, (10) white-eyed parakeets (Aratinga leucophthalma), (21) and larger psittacine birds. (22) Sequelae were rarely observed, and testicular cicatrization and divided testicular tissue occurred most frequently. In subsequent endoscopies, pathologic findings on the left testicle and the air sacs increased. In 1 cockatiel, the left testicle was absent after repeated sampling, indicating loss of testicular tissue via sampling or testicular atrophy. However, this phenomenon would not be expected after a single biopsy. Furthermore, one rose-ringed parakeet died during the fourth endoscopy because of severe bleeding. Nevertheless, bleeding complications occurred to a much lesser extent than in budgerigars (10) and swift parrots (Lathamus discol or), (23) probably because of the body size of the birds. About one-third of the birds showed no macroscopic testicular alterations until the fourth endoscopy.

Analogous to the results obtained in budgerigars, (10) testicular biopsies had only minor effects on sperm parameters. Sperm production stopped transiently around the second endoscopy in the rose-ringed parakeets, and sperm quality decreased after the third endoscopy in the cockatiels. Although testicular biopsy may be causative for these alterations, other factors must be considered. In the rose-ringed parakeets, the period of aspermia in April had begun already before the endoscopic procedure. Again, other factors must be considered, such as stress due to conflicts among the parakeets or the transfer to the outdoor aviaries. In the cockatiels, the affected sperm parameters remained low in the subsequent months but increased again after relocating the birds into the indoor aviaries. Thus, physiologic regression due to climatic changes may also be causative for decreasing sperm quality in July. In budgerigars, only minor effects of testicular biopsy on sperm quality were detected as well. (9) Nevertheless, studies in mammals reveal the occurrence of antisperm antibodies (ASA) after testicular biopsy. (24) The ASA are described to reduce sperm quality in men (25) and in stallions (26) but not in bulls (27) and dogs. (24) Whether ASA occur in psittacines is not known.

Our results show that taking a single biopsy sample from the testicle is a low-risk method for the evaluating the reproductive status of male parrots. Nevertheless, an impact on testicular integrity or on sperm quality cannot completely be ruled out, which is of special significance for endangered species. If taking a testicular biopsy is not required, endoscopic fine-needle aspiration for testicular cytologic examination, which has been described in swift parrots, (23) should be considered as a less invasive alternative.

Acknowledgments: We thank K. Steinbach-Sobiraj and Dr. A. Hahn for their collaboration. This project was supported by the Deutsche Forschungsgemeinschaft, Ei 333/12-2 and Kr 1732/5-1 and licensed by the responsible regional authority (Regierungsprasidium Leipzig, TVV 25/06).

References

(1.) IUCN. The IUCN Red List of Threatened Species Web site. http://www.iucnredlist.org/apps/redlist/ search [Psittaciformes]. Accessed December 28, 2011.

(2.) Harrison GJ. First psittacine produced by artificial insemination. Watchbird. 1982;9(3):36.

(3.) Hargrove TL. Cryogenic preservation of budgerigar, Melopsittacus undulatus, semen [master's thesis]. Boca Raton, FL: Florida Atlantic University; 1986.

(4.) Samour JH, Smith CA, Moore HDM, Markham JA. Semen collection and spermatozoa characteristics in budgerigars (Melopsittacus undulatus). Vet Rec. 1986;118(14):397-399.

(5.) Brock MK. Semen collection and artificial insemination in the Hispaniolan parrot (Amazona ventralis). J Zoo Wildl Med. 1991;22(1):107-114.

(6.) Anderson SJ, Bird DM, Hagen MD. Semen characteristics of the quaker parakeet (Myiopsitta monachus). Zoo Biol. 2002;21(5):502-512.

(7.) Behncke H. Spermagewinnung und -untersuchung sowie endoskopische Beurteilung des Geschlechtsapparats in Abhdngigkeit von der Spermaproduktion bei Psittaziden am Beispiel des Wellensittiehs (Melopsittacus undulatus) [dissertation]. Leipzig, Germany: Universitat Leipzig; 2002.

(8.) Behncke H, Stelzer G. Case report: semen collection, analysis and first attempt of artificial insemination (AI) in red-tailed cockatoos (Calyptorhynchus magnificus). Proc 7th Conf Euro Assoc Avian Vet, Teneriffa. 2003:367-369.

(9.) Stelzer G. Spermagewinnung, -untersuchung undfluissigkonservierung bei verschiedenen Papageienvogeln (Psittaciformes) [dissertation]. Leipzig, Germany: Universitat Leipzig; 2005.

(10.) Hanse M, Schmidt V, Schneider S, et al. Comparative examination of testicular biopsy samples and influence on semen characteristics in budgerigars (Melopsittacus undulatus). J Avian Med Surg. 2008;22(4):300-309.

(11.) DellaVolpe A, Schmidt V, Krautwald-Junghanns ME. Attempted semen collection using the massage technique in blue-fronted Amazon parrots (Amazo na aestiva aestiva). J Avian Med Surg. 2011;25(1): 1-7.

(12.) Taylor M. Endoscopic examination and biopsy techniques. In: Ritchie BW, Harrison G J, Harrison LR, eds. Avian Medicine: Principles and Application. Lake Worth, FL: Wingers Publishing Inc; 1994:327-354.

(13.) Hanse M, Krautwald-Junghanns ME, Reitemeier S, et al. Testicular biopsy in psittacine birds (Psittaciformes): comparative evaluation of testicular reproductive status by endoscopic, histologic, and cytologic examination. J Avian Med Surg. 2013; 27(4):247-257.

(14.) Pohl-Apel G, Sossinka R, Wyndham E. Gonadal cycles of wild budgerigars, Melopsittacus undulatus (Psittaciformes: Platycercidae). Aust J Zool. 1982; 30(5):791-797.

(15.) Krishnaprasadan TN, Kotak VC, Sharp P J, et al. Environmental and hormonal factors in seasonal breeding in free-living male Indian rose-ringed parakeets (Psittacula krameri). Horm Behav. 1988;22(4):488-496.

(16.) Maitra SK, Dey M. Importance of photoperiods in determining temporal pattern of annual testicular events in rose-ringed parakeets (Psittacula krameri). J Biol Rhythms. 1992;7(1):13-25.

(17.) Reitemeier S, Hanse M, Hahn A, et al. Evaluating the reproductive status of the male budgerigar (Melopsittacus undulatus). Gen Comp Endocrinol. 2011;171(3):350-358.

(18.) Samour JH, Moore HDM, Bailey IT, Watson PF. Annual testicular cycle in captive budgerigars (Melopsittacus undulatus). J Zool Lond. 1987;212(3): 465-473.

(19.) Kirby JD, Froman DP. Reproduction in male birds. In: Whittow GC, ed. Avian Physiology. 5th ed. New York, NY: Springer Verlag; 2000:597-615.

(20.) Birkhead TR. Male reproductive system, birds. In: Knobil E, Neill JD, eds. Encyclopedia of Reproduction. Vol 3. San Diego, CA: Academic Press; 1999:15-19.

(21.) Peixoto JV, Paula TAR, Balarini MK, et al. Morphofunctional evaluation of the testicle and the spermatogenic process of adult white-eyed parakeets (Aratinga leucophthalma Muller, 1776) during the different seasons of the year. Anat Histol Embryol. 2012;41(4):248-255.

(22.) Crosta L, Gerlach H, Burkle M, Timossi L. Endoscopic testicular biopsy technique in Psittaciformes. J Avian Med Surg. 2002;16(2):106-110.

(23.) Gartrell BD. Assessment of the reproductive state in male swift parrots (Lathamus discolor) by testicular aspiration and cytology. J Avian Med Surg. 2002;16(3):211-217.

(24.) Attia KA, Zaki AA, Eilts BE, et al. Anti-sperm antibodies and seminal characteristics after testicular biopsy or epididymal aspiration in dogs. Theriogenology. 2000;53(6): 1355-1363.

(25.) Mandelbaum SL, Diamond MP, DeCherney AH. The impact of antisperm antibodies on human infertility. J Urol. 1987;138(1):1-8.

(26.) Zhang J, Ricketts SW, Tanner SJ. Antisperm antibodies in the semen of a stallion following testicular trauma. Equine Vet J. 1990;22(2): 138-141.

(27.) Purswell B J, Dawe DL, Caudle AB, et al. Spermagglutinins in serum and seminal fluids of bulls and their relationship to fertility classification. Theriogenology. 1983;20(4):375 381.

Maria Hanse, MedVet, Maria-Elisabeth Krautwald-Junghanns, Prof Dr MedVet, Dipl ECZM (Avian), Susanne Reitemeier, MedVet, Almuth Einspanier, Prof Dr MedVet, and Volker Schmidt, Dr MedVet, Dipl ECZM (Avian)

From the Clinic for Birds and Reptiles (Hense, Krautwald-Junghanns, Schmidt) and Institute of Physiological Chemistry (Reitemeier, Einspanier), Veterinary Faculty, University of Leipzig, An den Tierkliniken 17, 04103 Leipzig, Germany.
COPYRIGHT 2013 Association of Avian Veterinarians
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2013 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Hanse, Maria; Krautwald-Junghanns, Maria-Elisabeth; Reitemeier, Susanne; Einspanier, Almuth; Schmidt
Publication:Journal of Avian Medicine and Surgery
Article Type:Report
Date:Dec 1, 2013
Words:2618
Previous Article:Testicular biopsy in psittacine birds (psittaciformes): comparative evaluation of testicular reproductive status by endoscopic, histologic, and...
Next Article:Comparison of osmolality and refractometric readings of Hispaniolan Amazon parrot (Amazona ventralis) urine.
Topics:

Terms of use | Privacy policy | Copyright © 2019 Farlex, Inc. | Feedback | For webmasters