Correlation between the presence of a cecal appendix and reduced diarrhea severity in primates: new insights into the presumed function of the appendix.

Increased severity or recurrence risk of some specific infectious diarrhea, such a salmonellosis or Clostridium difficile colitis, have been reported after an appendectomy in human patients. While several other mammals also possess an appendix, the suspected protective function against diarrhea conferred by this structure is known only in humans. From a retrospective collection of veterinary records of 1251 primates attributed to 45 species, including 13 species with an appendix and 32 without, we identified 2855 episodes of diarrhea, 13% of which were classified as severe diarrhea requiring a therapeutic medication or associated with a fatal issue. We identified a lower risk of severe diarrhea among primate species with an appendix, especially in the early part of life when the risk of diarrhea is maximal. Moreover, we observed a delayed onset of diarrhea and of severe diarrhea in species possessing an appendix. Interestingly, none of the primates with an appendix were diagnosed, treated or died of an acute appendicitis during the 20 years of veterinarian follow-up. These results clarify the function of the appendix among primates, as protection against diarrhea. This supports its presumed function in humans and is congruent with the existence of a selective advantage conferred by this structure.

Intestinal Protists in Captive Non-human Primates and Their Handlers in Six European Zoological Gardens. Molecular Evidence of Zoonotic Transmission.

We assessed the occurrence, genetic diversity, and zoonotic potential of four protozoan (Cryptosporidium spp., Entamoeba histolytica, Entamoeba dispar, Giardia duodenalis), one stramenopile (Blastocystis sp.), one microsporidia (Enterocytozoon bieneusi), and two ciliate (Balantioides coli, Troglodytella abrassarti) intestinal parasite or commensal protist species in captive non-human primates (NHP) and their zookeepers from six European zoological gardens in France (n = 1), Germany (n = 1), and Spain (n = 4). Faecal samples from NHP (n = 454) belonging to 63 species within 35 genera and humans (n = 70) were collected at two sampling periods in each participating institution between October 2018-August 2021. Detection and species identification was accomplished by PCR and Sanger sequencing of the ssu rRNA and/or ITS genes. Sub-genotyping analyses using specific markers were conducted on isolates positive for G. duodenalis (gdh, bg, tpi) and Cryptosporidium spp. (gp60). Overall, 41.0% (186/454) and 30.0% (21/70) of the faecal samples of NHP and human origin tested positive for at least one intestinal protist species, respectively. In NHP, Blastocystis sp. was the most prevalent protist species found (20.3%), followed by G. duodenalis (18.1%), E. dispar (7.9%), B. coli and T. abrassarti (1.5% each), and Cryptosporidium spp. and E. bieneusi (0.9% each). Occurrence rates varied largely among NHP host species, sampling periods, and zoological institutions. The predominant protist species found in humans was Blastocystis sp. (25.7%), followed by Cryptosporidium spp. (2.9%), E. dispar (1.4%), and G. duodenalis (1.4%). Sequencing of PCR-positive amplicons in human and/or NHP confirmed the presence of Cryptosporidium in six isolates (C. hominis: 66.7%, C. parvum: 33.3%), G. duodenalis in 18 isolates (assemblage A: 16.7%, assemblage B: 83.3%), Blastocystis in 110 isolates (ST1:38.2%, ST2:11.8%, ST3: 18.2%, ST4: 9.1%, ST5: 17.3%, ST8: 2.7%, ST13: 0.9%), and E. bieneusi in four isolates (CM18: 75.0%, Type IV: 25.0%). Zoonotic transmission events involving Blastocystis ST1-ST4 were identified in four zoological institutions. Zoonotic transmission of C. hominis was highly suspected, but not fully demonstrated, in one of them. Monitoring of intestinal protist species might be useful for assessing health status of captive NHP and their zookeepers, and to identify transmission pathways of faecal-orally transmitted pathogens.

SURGICAL ORCHIECTOMY IN FRUIT BATS-DESCRIPTION OF TWO TECHNIQUES IN THE RUWENZORI LONG-HAIRED FRUIT BAT (ROUSETTUS LANOSUS) AND THE JAMAICAN FRUIT-EATING BAT (ARTIBEUS JAMAICENSIS).

Contraception is needed to prevent overpopulation and inbreeding in highly fecund captive bat colonies. Reports on surgical contraception in bats are limited. The objective of this study was to describe surgical castration techniques in a megachiropteran and a microchiropteran fruit bat species. Open orchiectomy by transfixing ligation of the spermatic cord was performed in 14 Ruwenzori long-haired fruit bats (Rousettus lanosus) (RL-LIG), and orchiectomy with radiosurgery alone was performed in 125 Jamaican fruit-eating bats (Artibeus jamaicensis) (AJ-RS) and one Ruwenzori bat (RL-RS). The surgical techniques were not compared in different species with the exception of the one Ruwenzori bat operated with RS. Anesthesia was induced and maintained with isoflurane in oxygen via facemask. Preoperatively, all bats received butorphanol and subcutaneous fluids. Meloxicam was administered postoperatively for the RL-LIG. For the RL-LIG, anesthesia lasted 49 ± 15 min (mean ± SD) with a total surgery time of 26 ± 12 min. In comparison, the RS was considerably shorter, lasting 10 ± 3 min for anesthesia and 5 ± 2 min for surgery. Complications were rare, with a morbidity rate of 6.7% with the RL-LIG (prolonged recovery [n = 1]) and of 4.8% with the RS (dyspnea [n = 3], hemorrhage [n = 2], and prolonged recovery [n = 1]). One of the cases of hemorrhage was in the single Ruwenzori bat castrated using the RS technique. Mortality rate was 1.6% (n = 2) with the RS. No mortality occurred with the RL-LIG. In conclusion, using radiosurgery alone appears to be a safe and rapid surgical technique in smaller species of fruit bats. For larger species, such as the Ruwenzori fruit bats, ligation or use of an advanced vessel sealing system is recommended.