Is there a relationship between serum minerals (Ca, Mg) and trace elements (Cu, Fe, Mn, Zn) at mating on pregnancy rates in fat-tailed Morkaraman sheep?

Abstract

The specific roles of nutrients in reproduction are not well defined in sheep. Hence, the relationships between certain mineral (Ca, Mg) and element (Cu, Fe, Mn, Zn) levels at mating and pregnancy rates was investigated in fat-tailed Morkaraman ewes synchronised with different hormones (melatonin, norgestomet implant and eCG) early in anoestrus season. For this purpose, 40 healthy ewes (aged 2-4 years) allocated in the synchronised (n=30) and no-treated group (n=10) were used during mid-May (suckling period). On the eCG injection day, fertile rams (n=8) were introduced into the groups and, then the oestrus signs were visually monitored twice daily for 7 days. The oestrous ewes were allowed to handmate using rotational (four rams daily) mating system. Additionally, jugular blood samples were collected on the days of onset of oestrus (before mating) for determination of serum Ca, Cu, Fe, Mg, Mn and Zn levels. Presence of pregnancies was diagnosed by real-time ultrasonography 35 days post-mating. Totally, 25 ewes became pregnant (21 ewes with stimulatedand 4 with spontaneous oestrus), while 9 ewes (all received stimulation) were not pregnant. In non-pregnant ewes, unlike other minerals and elements, the Cu and Zn values were significantly lower than their reference values (for Cu: 0.87±0.16 mg/dl vs. 9.20 mg/dl; for Zn: 2.06±0.30 g/dl vs. 3.8 g/dl, resp.; P<0.01 in both cases). In pregnant ewes, the corresponding values remained unchanged (P>0.05). Hence, the present findings indicate that the low Cu and Zn levels during the oestrus might adversely affect the subsequent pregnancy rate in suckling ewes.

Oestrus synchronisation with progesterone-containing sponge and equine chorionic gonadotropin in Pirlak ewes during the non-breeding season: can Toryum improve fertility parameters?

“…These vitamins, minerals, and trace elements in particular may have shown a positive effect on the fertility parameters. As support for this idea, in Red Karaman ewes that were synchronised in anoestrus, the Cu and Zn concentration decreased during mating, and this influenced the pregnancy rate negatively (28). In ruminants, while anoestrus, delayed oestrus, reduced pregnancy rate, embryo death, and stillbirth may occur in Cu deficiency (27), in the case of decreased serum Zn concentration, pregnancy and oestrus rates decrease (15,29).…”

Causes and Remedies for Non-Infectious Infertility in Sheep and Goats

“…During the mating season, females should be given additional energy and protein supplements (250 grs corn and barley, 300-600 gr barley or 500 gr mixed feed, either), as a flushing diet, for 1-2 months to support reproductive activities (Aytuğ et al, 1990;Elmas, 2013). Care should be taken for breeding males to be fed with high-quality grass with vitamin-mineral support (Uslu et al, 2017) and concentrated feed (Aytuğ et al, 1990;Elmas, 2013). However, excessive feeding (fattening) of breeding rams and bucks should never be allowed (Uçar et al, 2008).…”

“…Otherwise, low libido, fatigue, and hoof problems may be encountered more frequently. Salt, mineral (calcium, phosphorus, iron, copper, zinc, selenium) and vitamin (A-D-E) needs (especially mating, milking, pregnancy, and growth periods) should be met regularly and adequately (Uçar et al, 2011;Sönmez, 2012;Ömür et al, 2016;Uslu et al, 2017). Nutritional disorders (weakening and gatro-intestinal foreign bodies such as wool balls or bezoars) can be seen both in sheep and goats (Figure 1).…”

​​Factors Affecting Serum Trace Elements of Breeding Ewes in Central Saudi Arabia

“…Manganese (Mn) is compulsory for growth, digestion and reproduction in ruminants. Retarded growth and poor ossification and high rate of bone fractures were noted in ewes raised on low manganese diets (Grace and Knowles, 2012; Uslu et al, 2017). Selenium (Se) is a cell antioxidant, which prevents harm of free oxygen and several peroxides formed from fatty acids (Gürdoğan et al, 2006;Ganie et al, 2014;Makhlouf et al, 2020).…”