Semen cryopreservation and radical reduction capacity of seminal fluid in captive African lion (Panthera leo)

Optimizing cryopreservation protocols for nondomestic felids contributes to the successful development of assisted reproduction techniques and genetic resource banking. In this study, we describe a simple cryopreservation procedure for African lion (Panthera leo) ejaculates, which was tested with different packaging options and different sperm numbers per dose. By applying urethral catheterization and electroejaculation, 17 ejaculates with greater than 20% motile and greater than 5% progressively motile sperm were collected. A lyophilized extender (a modified egg yolk-Tes-Tris-fructose-glycerol medium) was rehydrated and added in one step at ambient temperature (∼25 °C) to semen, which was prediluted in cell culture medium M199. After slow cooling of insulated samples to 15 °C in a refrigerator (4 °C), the samples were fast frozen over the surface of liquid nitrogen or in a dry shipper. Aliquots of 300 μL containing 20 × 106 sperm were frozen in cryovials and in 0.5-mL straws. Differences were observed in the total motility after thawing between vial (31.5 ± 14.1%) and straw freezing (20.1 ± 8.6%). However, the subpopulations of vital (22.7 ± 7.8% for vial and 19.8 ± 8.5% for straw) and progressively motile (10.0 ± 7.9% for vial and 10.0 ± 6.4% for straw) sperm after washing and 1 hour incubation at 38 °C were of similar magnitude, velocity, and linearity for both packaging options. After freezing of five ejaculates with 20, 60, and 100 × 106 sperm per dose, best results were achieved at the lowest concentration. In general, post-thaw results were highly variable (2.2% and 56.5% total motility) and not correlated to motility or morphology of the fresh semen. To further characterize semen quality, we assessed the protective potential of seminal fluid against oxidative stress, which might be challenged on freeze thawing. The capacity of seminal fluid to reduce radicals was measured in 10 semen samples by electron spin resonance spectroscopy and a spin-labeled fatty acid as a radical probe. Moreover, we determined the lysophosphatidylcholines (LPC) as potential lipid oxidation products in the sperm and erythrocytes of the males. Individuals with a high radical reduction capacity in the seminal fluid and a low LPC content in their erythrocytes showed a better cryosurvival of sperm. This is a first indication that seminal fluid may affect the freezing potential of African lion ejaculates.The German Ministry of Education and Research (BMBF Number 033L046) and by a grant of the German Research Council to J. S. and K. M. (DFG SCHI 476/12–1&2 and MU 1520/4–1&2).http://www.theriojournal.com2018-02-27hj2017Paraclinical Science

Non-invasive assessment of adrenocortical activity as a measure of stress in giraffe (Giraffa camelopardalis)

Additional file 1: Full dataset in Microsoft Excel workbook format.BACKGROUND : Numbers of giraffes are declining rapidly in their native habitat. As giraffe research and conservation efforts increase, the demand for more complete measures of the impact of conservation interventions and the effects of captive environments on animal health and welfare have risen. We compared the ability of six different enzyme immunoassays to quantify changes in fecal glucocorticoid metabolites (FGM) resulting from three sources: adrenocorticotropic hormone stimulation test, transport, and time of day that samples were collected. RESULTS : Two male giraffes underwent ACTH injections; all six assays detected FGM increases following injection for Giraffe 1, while only three assays detected FGM increases following injection for Giraffe 2. Consistent with other ruminant species, the two 11-oxoetiocholanolone assays (one for 11,17-dioxoandrostanes and the other for 3α,11-oxo metabolites) measured the most pronounced and prolonged elevation of FGM, while an assay for 3β,11β-diol detected peaks of smaller magnitude and duration. Both of the 11-oxoetiocholanolone assays detected significant FGM increases after transport in Giraffes 3–7, and preliminary data suggest FGM detected by the assay for 11,17-dioxoandrostanes may differ across time of day. CONCLUSIONS : We conclude the assay for 11,17-dioxoandrostanes is the most sensitive assay tested for FGM in giraffes and the assay for FGM with a 5β-3α-ol-11-one structure is also effective. 11-oxoetiocholanolone enzyme immunoassays have now been demonstrated to be successful in a wide variety of ruminant species, providing indirect evidence that 5β-reduction may be a common metabolic pathway for glucocorticoids in ruminants. As FGM peaks were detected in at least some giraffes using all assays tested, giraffes appear to excrete a wide variety of different FGM. The assays validated here will provide a valuable tool for research on the health, welfare, and conservation of giraffes.The Association of Friends and Supporters of Goethe University Frankfurt provided financial support for F. Sicks to travel to Vienna to analyze fecal samples and von Opel Hessische Zoostiftung supported a studentship for F. Sicks. One commercial funder [Tierpark Berlin] provided support in the form of salary for F. Sicks during data analysis and preparation of this manuscript. The specific role of this author is articulated in the ‘Author Contributions’ section.http://www.biomedcentral.com/bmcvetresam2016Anatomy and PhysiologyParaclinical Science

Determining adrenocortical activity as a measure of stress in African buffalo (Syncerus caffer) based on faecal analysis

Little is known about the levels of stress experienced by African buffalos affected by injury, disease, or socio-ecological and  anthropogenic factors. To be able to start filling this gap, we examined the suitability of two 11-oxoaetiocholanolone enzyme-immunoassays (EIAs) detecting 11,17 dioxoandrostanes (11,17-DOA) as well as faecal glucocorticoid metabolites (FGMs) with a 5-3-ol-11-one structure (3 ,11oxo-CM), respectively, for monitoring stress-related physiological responses in African buffalo. An adrenocorticotrophic hormone (ACTH) challenge in one male and one female housed at Mokopane Biodiversity Conservation Centre, South Africa, showed a threefold increase in circulating cortisol levels in a sample taken 40 min post-injection.   Corresponding 11,17-DOA levels increased tenfold (female) and 15-fold (male) above baseline, and 3,11oxo-CM concentrations increased ninefold (female) and 12-fold (male) above pre-injection levels, indicating that both EIAs are suitable for measuring FGMs in African buffalo.In addition, 11,17-DOA levels monitored during the adaptation process of individual housing revealed an up to 14-fold elevation in FGMs. Storage of faeces at ambient temperature for up to 16 h post-defecation resulted in an significant increase in 11,17-DOA levels 2 h after defecation. Finally, higher individual baseline 11,17-DOA concentrations were found in samples defecated overnight, indicating a possible diurnal effect in excretion of FGMs in African buffalo.Key words: faecal glucocorticoid metabolites, ACTH challenge test, animal separation, hormone degradation rate, circadian variatio

Terrestrial mammal three-dimensional photogrammetry: multispecies mass estimation

Assessing body mass in mammals is of importance as it influences virtually all aspects of mammal physiology, behavior and ecological parameters. However, the assessment of body mass of large mammals is potentially dangerous and logistically challenging. Photogrammetry (measurements through the use of photographs) is a well-established science. In zoology it has been used with varying success to estimate the size and mass of some marine and terrestrial mammal species. However, photogrammetric body mass estimation of terrestrial mammals has received comparatively little attention. This is largely due to species' variable morphological attributes which complicates measurement especially if, for 3D orientation, photogrammetric models are dependent on identifiable features on the animals themselves. Ninety-two individuals belonging to 16 terrestrial mammalian species were weighed and photographed for body mass estimation using a volumetric photogrammetry method, purposely applied with commercially available software. This method is not dependent on identifiable body features for 3D orientation. Measured body mass ranged from 25 kg to 4060 kg. Photogrammetric mass estimates versus physically weighed mass was plotted and the goodness of fit assessed for each species. Body size, shape and physiological attributes influence the accuracy of body mass estimation between species (although consistent within species), largely attributed to morphological features (e.g., hair length and posture). This photogrammetric method accurately estimated the body mass of several terrestrial mammal species. It represents innovative use of photographs to create calibrated three-dimensional imagery for accurate quantification of mammalian metrics, specifically body volume and mass. Advances of a method that is not subject to species, sex or age is advantageous and suitable for wide application in our effort to model population demography.</p

Appendix B. A figure showing species specific correction factors decrease for approximating body mass estimation.

A figure showing species specific correction factors decrease for approximating body mass estimation