β-carotene Supplementation Increases Progesterone Concentration and Glutathione Peroxidase Activity Following Alternative Progesterone Primed Oestrous Synchronization Protocol in Goats

Abstract

The present study evaluated the effect of β-carotene supplementation and oestrous synchronization protocol on ovarian activity and fertility of Saanen does during the breeding season. The supplemented group received 100 mg β-carotene during the breeding and all does were synchronised with Controlled Internal Drug Release dispenser (CIDR) and injected with cloprostenol at CIDR withdrawal. One group of does were injected with 300 IU of eCG, while in another group bucks wearing aprons were introduced at CIDR withdrawal. Does were artificially inseminated twice (48 and 60 h) with fresh undiluted semen. The onset and duration of oestrus, progesterone, oestrdiol-17β and glutathione peroxidase activity, oestrous response and conception rate were analysed. Synchronization protocol did not affect response to oestrus, onset and duration of oestrus and oestradiol-17β concentration. The male presence group had significantly higher conception rate (97%) than the eCG (72%) group. βcarotene supplemented group had higher progesterone concentration and glutathione peroxidase activity. Supplemental β-carotene during the breeding period therefore, could play an important role on establishment of pregnancy due to high progesterone concentration and glutathione peroxidase activity. Inclusion of male effect in progesterone based oestrous synchronization protocol improves conception rate. Therefore, male effect can be used as an alternative to equine chorionic gonadotropin in progesterone based oestrous synchronization protocols especially, where drugs for oestrous synchronization are not affordable.

Effects of hesperidin on the oestrous cycle of Yankasa ewes

“…This agrees with the findings of Musa et al (2018), who found higher ORR in Yankasa ewes supplemented with Vitamin E and selenium. However, it disagrees with the report of Sejian et al (2014) in Malpura ewes administered mineral and antioxidants as well as the report of Gore & Lehloenya (2020) in Saanen goats supplemented with β-carotene, where there was no effect. Oxidative stress is associated with the different stages of the oestrous cycle during which excess reactive oxygen species (ROS) are produced, resulting in deleterious effects on ewes, particularly poor oestrus outcomes.…”

Use of Short-Term CIDR-Based Protocols for Oestrus Synchronisation in Goats at Tropical and Subtropical Latitudes

“…Considering this limitation, the use of other forms of short-term energy supplies can be explored. Apart from the influence of glycogenic mixtures on follicular dynamics and the ovulation rate [41,83,84], fertility traits such oocyte competence, fertilisation rate, and embryo quality can also be influenced through supplementation with high energy diets, [82,90], high protein-energy diets [83], fatty acids [88,89], or β-carotene [87]. It is important to note that body weight (BW) and BCS are not influenced by short-term energy [90] or micronutrient supplementation [86].…”

“…Short-term nutritional supplementation can be accomplished using high energy diets [ 82 ] or infusions such as glycogenic mixtures (glycerol + propylene glycol + water) [ 41 , 83 , 84 ]. Other nutritional supplements include high protein-energy diets [ 85 ] and micronutrients such as betacarotene (β-carotene) [ 86 , 87 ] or fatty acids (FAs) [ 88 , 89 ]. When supplied at specific physiological stages, the metabolic status, follicle development, oocyte/embryo quality, or ovulation rate are influenced and, consequently, fertility is improved ( Figure 5 ).…”

“…Furthermore, for a significant effect of short-term energy supplementation on the ovulation rate to be achieved, nutrients have been supplied from the mid to late luteal phase, i.e., shortly before P4 withdrawal or luteolysis [ 82 , 90 ], with the timing designed in such a way that levels of glucose and metabolic hormones peak around the time of emergence of the ovulatory wave [ 90 ]. As for supplementation aimed at influencing embryo survival, nutrients are supplied beyond the luteal phase (i.e., through to the follicular phase to target the critical stage of pregnancy establishment [ 87 ]). For example, the pregnancy rate was influenced ( p < 0.05) in anovulatory female goats under extensive grazing conditions, which exposed to ME for 15 days and fed a high protein diet for 7 days, starting 9 days after male introduction, compared with non-supplemented goats, although the effect was greater ( p < 0.05) with a 14-day supplementation period (i.e., supplementation was provided for 7 more days after male exposure).…”

“…In another study with FAs, inclusions of omega-3 and omega-6 fatty acids from linseed oil in the diet of Boer goats synchronised with a protocol to achieve superovulation resulted in a higher ( p < 0.05) mean number of recovered ova/embryos and transferable embryos, in addition to the prevention of premature CL regression [ 89 ]. Embryo loss can also be prevented by β-carotene supplementation [ 87 ]. For example, β-carotene supplementation increased the P4 concentration and glutathione peroxidase activity in Saanen goats, which signifies that β-carotene could have a key role in improving fertility through the establishment of pregnancy and/or improved embryo survival.…”