The literature available on the agouti (Dasyprocta leporina) is very limited. The agouti is a Neotropical rodent found in Trinidad and Tobago, Central and South America. This study focuses on one of the many unexplored areas relating to the species, the male reproductive system. The results showed that the mean testicular length, diameter and weight was 3.67 +/- 0.12 cm, 1.67 +/- 0.04 cm and 5.03 +/- 0.52 g respectively. The paired testes and epididymis were found in contact with the abdominal muscles within scrotal pouches, which are evaginations of the caudoventral abdominal wall. The caput epididymis is enclosed by a fat body. The ductus deferens has a mean length and diameter of 10.98 +/- 0.40 cm and 0.14 +/- 0.01 cm respectively. At the urethral end of the ductus deferens the diameter of each duct expends to form the ampulla. The mean diameter of each of the ampulla was 0.25 cm. The accessory sex organs of the male agouti (D. leporina) include the vesicular glands, the coagulating glands, the prostate glands and the bulbourethral glands. The penis of the agouti is U-shaped with a mean length of 9.90 +/- 0.43 cm. The glans penis contains an os penis, a pair of lateral penile cartilages and paired ventral keratinaceous styles.

This study was a follow up to the study on the gross anatomy of the male agouti (Dasyprocta leporina) reproductive system. The seminal vesicles of the agouti are lobulated structures. The mean diameter of the large lumen is 883.6 +/- 76.83 microm. The mucosa (24.1 +/- 0.92 microm), which is lined by pseudo-stratified columnar epithelium is thrown into folds, which often branch. The lamina muscularis mucosa is thin and is made of loose connective tissue containing blood vessels. The mucosa of the leaf-like coagulating glands of the agouti is folded. The mean diameter of the lumen is 488.3 +/- 41.96 microm. The mucosa contains tubuloalveolar glands, which have a mean length of 199.5 +/- 28.83 microm. The thin epithelium, 15.0 +/- 1.25-microm wide, consists mostly of pseudo-stratified columnar cells. The epithelium also has surface modifications in the form of apical blebs and cilia. The epithelium of the agouti's lobulated prostate gland is also folded creating a large lumen with a mean diameter of 995.5 +/- 55.70 microm. The mucosa contains tubular and tubuloalveolar glands, each having a mean length of 134.4 +/- 13.59 microm. The epithelium (13.9 +/- 1.16 microm) consists of pseudo-stratified columnar cells. The pea-shaped bulbourethral gland (BG) of the agouti consists of convoluted tubular, mucous secretory units, which are irregularly shaped each with a mean length of 177.9 +/- 7.10 microm and a mean width of 63.5 +/- 3.97 microm. The BG of the agouti are ventro-lateral to the rectum and dorsally positioned to the pubic symphysis, and connected to the urethra by short ducts.

This study evaluated the effects of semen extension and storage on forward progressive motility % (FPM%) in agouti semen. Three extenders were used; sterilized whole cow's milk (UHT Milk), unpasteurized (CW) and pasteurized coconut water (PCW), and diluted to 50, 100, 150, and 200 × 106 spermatozoa/ml. Experiment 1: 200 ejaculates were extended for liquid storage at 5∘C and evaluated every day for 5 days to determine FPM% and its rate of deterioration. Experiment 2: 150 ejaculates were extended for storage as frozen pellets in liquid nitrogen at −195∘C, thawed at 30∘ to 70∘C for 20 to 50 seconds after 5 days and evaluated for FPM% and its rate of deterioration. Samples treated with UHT milk and storage at concentrations of 100 × 106 spermatozoa/ml produced the highest means for FPM% and the slowest rates of deterioration during Experiment 1. During Experiment 2 samples thawed at 30∘C for 20 seconds exhibited the highest means for FPM% (12.18 ± 1.33%), 85% rate of deterioration. However, samples were incompletely thawed. This was attributed to the diameter of the frozen pellets which was 1 cm. It was concluded that the liquid storage method was better for short term storage.

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This study tested various combinations of ketamine and xylazine with the objective to improve on the efficiency of the preliminary electroejaculation technique developed for semen collection from the agouti (Dasyprocta leporina). There were two experiments, which were each replicated. Experiment 1 had six treatments: treatment 1 (30 mg/kg ketamine and 10 mg/kg xylazine), treatment 2 (20 mg/kg ketamine and 10 mg/kg xylazine), treatment 3 (30 mg/kg ketamine and 5 mg/kg xylazine), treatment 4 (20 mg/kg xylazine), treatment 5 (30 mg/kg xylazine), and treatment 6 (40 mg/kg xylazine). Experiment 2 included five treatments: treatment 7 (40 mg/kg xylazine), treatment 8 (20 mg/kg ketamine and 40 mg/kg xylazine), treatment 9 (15 mg/kg ketamine and 40 mg/kg xylazine), treatment 10 (10 mg/kg ketamine and 40 mg/kg xylazine), and treatment 11 (5 mg/kg ketamine and 40 mg/ kg xylazine). Mean induction times were 3:27 +/- 0:31 and 4:59 +/- 0.49; mean immobilization times were 1:55 +/- 0.11 and 1:19:06 +/- 0:11.7 hr, respectively, for experiments 1 and 2. Treatment 4 produced the best ejaculation time and semen volume, 4.53 +/- 0.52 min and 0.41 +/- 0.07 ml, respectively. Spermatozoa were observed in 75% of ejaculate samples collected when treatments 6 and 7 were applied. The best treatments were 6 and 7 (P < 0.05); spermatozoa concentration (431 +/- 180 x 106/ml), motile cell % (47.17 +/- 8.78%) and forward progressive motility % (47.1 +/- 10.5%). Success rates for samples containing spermatozoa increased from 30% in previous experiments to 41.33%. It was concluded that weaker dosages of xylazine may require being administered in combination with ketamine to completely anaesthetize the male agouti for electroejaculation.