Feed Concentrate Palatability in Welsh Ponies: Acceptance and Preference of Flavors.

In horses, it is well established that nutrients and the palatability of feed material (odor and taste) play an important role in diet selection. For example, high-fiber feed taste is not well accepted by horses. Consequently, manufacturers have begun to supplement horse feed with flavors to mask feed bitterness, to overcome feed neophobia and to encourage water drinking. However, only few studies have been performed to evaluate the acceptance and preference of flavors in horses. The aim of this study was to evaluate the acceptance and preference of flavors supplemented on top of concentrate offered to ponies. Thirty-three female Welsh ponies aged between four to 13 years were enrolled in the experiment. Ponies were offered 4 flavored concentrates and one control with no flavor. The flavored concentrates were anise, caramel, raspberry and apple. The inclusion rate of the flavors was 300 g/t on an as-is basis. During the adaptation period (one week), the ponies were gently guided to each bucket containing the flavored concentrate (200 g) during 10 sec/bucket for olfaction only. During the test period, ponies were allowed to freely choose flavored concentrates for 2 minutes. The flavors and the position of the buckets in front of the ponies were randomized. Each period was video-recorded and number of chews were counted during test period. The concentrate intake, eating time, and animal behavior were recorded during the test period. The apple concentrate was consumed the most at 116 g/2-min offering, whereas the raspberry and control concentrates were consumed the least, at 85.31 and 90.80 g/2-min offering, respectively. Apple flavor was preferred over caramel, raspberry and anise as indicated by higher consumption rate (g/sec) (chi-squared=16.68, df=4, P<0.05). There was no effects on chews, smell or headshaking time per sec between treatments. In conclusion, the ponies accepted a wide range of flavors with a preference for apple over raspberry flavored concentrate.

First attempts for vitrification of immature oocytes in donkey (Equus asinus): Comparison of two vitrification methods.

Most wild donkey breeds are severely threatened by poaching for meat, habitat loss, and competition with livestock for food resources. Moreover, due to the mechanization in agriculture and in transport, most domestic donkey breeds are at risk of extinction. Considering the importance of biodiversity and preservation of genetic resources, the creation of genetic banks for endangered donkey breeds is urgently needed. Cryopreservation of immature jennies oocytes would be an efficient tool to allow storage of female genetics. The aim of the present study was to establish conditions for immature donkey oocyte vitrification, using equine oocytes as a control. Asine and equine immature cumulus-oocyte complexes were collected by transvaginal ultrasound-guided follicular aspiration and flushed to obtain oocytes surrounded by only corona radiata. Oocytes were vitrified after exposure to increasing concentrations of dimethyl sulfoxide, ethylene glycol and sucrose as cryoprotectants in a solution of INRA-Freeze™ medium or TCM199-Hepes supplemented with bovine serum albumin. Oocytes were warmed in decreasing concentrations of sucrose and processed for in vitro maturation. The recovery rate was 48% for jennies oocytes (4.8 oocyte per female) and 42% for mares oocytes (3.5 oocyte per female). When oocytes were exposed to cryoprotectants in INRA-Freeze™ medium none of the jennies re-warmed oocytes matured, whereas 24% of the mares re-warmed oocytes reached metaphase II after in vitro maturation. When oocytes were exposed to cryoprotectants in TCM199-Hepes-BSA medium, 33% of the jennies re-warmed oocytes matured. In conclusion, we developed a method for the vitrification of immature oocytes from jennies that allows in vitro maturation of the vitrified-warmed asine oocytes. Their competence for fertilization and development has to be ascertain.

Influence of transvaginal ultrasound-guided follicular punctures in the mare on heart rate, respiratory rate, facial expression changes, and salivary cortisol as pain scoring.

Transvaginal ultrasound-guided follicular punctures are widely used in the mare for diagnosis, research, and commercial applications. The objective of our study was to determine their influence on pain, stress, and well-being in the mare, by evaluating heart rate, breath rate, facial expression changes, and salivary cortisol before, during, and after puncture. For this experiment, 21 pony mares were used. Transvaginal ultrasound-guided aspirations were performed on 11 mares. After injections for sedation, analgesia, and antispasmodia, the follicles from both ovaries were aspirated with a needle introduced through the vagina wall into the ovary. In the control group, 10 mares underwent similar treatments and injections, but no follicular aspiration. Along the session, heart rate and breath rate were evaluated by a trained veterinarian, ears position, eyelid closure, and contraction of facial muscles were evaluated, and salivary samples were taken for evaluation of cortisol concentration. A significant relaxation was observed after sedative injection in the punctured and control mares, according to ear position, eyelid closure, and contraction of facial muscles, but no difference between punctured and control animals was recorded. No significant modification of salivary cortisol concentration during puncture and no difference between punctured and control mares at any time were observed. No significant modification of the breath rate was observed along the procedure for the punctured and the control mares. Heart rate increased significantly but transiently when the needle was introduced in the ovary and was significantly higher at that time for the punctured mares than that for control mares. None of the other investigated parameters were affected at that time, suggesting discomfort is minimal and transient. Improving analgesia, e.g., through a multimodal approach, during that possibly more sensitive step could be recommended. The evaluation of facial expression changes and heart rate is easy-to-use and accurate tools to evaluate pain and well-being of the mare.

Establishment of conditions for ovum pick up and IVM of jennies oocytes toward the setting up of efficient IVF and in vitro embryos culture procedures in donkey (Equus asinus).

Most wild and domestic donkey breeds are currently endangered or threatened. Their preservation includes the creation of a Genome Resource Bank. Embryos cryopreservation allows the preservation of genetics from both male and female and is the fastest method to restore a breed. Because embryo production in vivo is limited in equids, our objective was to establish conditions for in vitro production of embryos in donkey using ovum pick up (OPU), IVM, IVF, and in vitro culture of zygotes. Donkey cumulus-oocyte complexes (COCs) were collected by transvaginal ultrasound-guided aspirations OPU in adult cyclic jennies and in vitro matured in tissue culture medium 199 supplemented with fetal calf serum and epidermal growth factor for 24, 30, 34, or 38 hours. They were preincubated with oviductal fluid for 30 minutes, coincubated with frozen-thawed donkey semen treated with procaine for 18 hours, and cultured for 30 hours in Dulbecco's Modified Eagle Medium-F12 supplemented with NaHCO3, fetal calf serum, and gentamycin. From the five OPU sessions, we collected 92 COCs in 193 follicles (48%) with an average of 4.2 COCs per jenny. All COCs were expanded after more than 24-hour IVM. At collection, jennies oocytes contained a germinal vesicle. Metaphase 1 oocytes were observed after 30-hour IVM and 44% were in metaphase 2 after 34-hour IVM. In our conditions, IVM of donkey oocytes was slower than IVM of equine oocytes and optimal duration for donkey oocytes IVM may be 34 hours. Only 15% of jennies oocytes contained two pronuclei after coincubation with donkey spermatozoa and none of them developed further after 48 hours post-IVF. Moreover, some parthenogenetic activation occurred. Thus, the treatment of donkey sperm with procaine may not be efficient for IVF. In conclusion, we established for the first time conditions for OPU in jennies with high recovery rates. We reported that IVM of jennies oocytes can produce 44% of metaphase 2 oocytes after 34 hours in culture and we described for the first time the chronology of IVM of donkey oocytes. Further studies are in progress to establish efficient conditions for IVF and development of donkey zygotes.