Fertility of Ewes Inseminated Intrauterinally with Frozen Semen Using Extender Containing Bovine Serum Albumin

Abstract

Abstract. The present study was conducted to examine the fertility of ewes inseminated intrauterinally with frozen semen using semen extender containing either egg yolk or bovine serum albumin (BSA). Sixty Suffolk and cross-bred ewes were treated with controlled internal drug release (CIDR) devices during the non-breeding season (July 2006). A CIDR was inserted into the vagina for 12 days and an intramuscular injection of 500 IU equine chorionic gonadotropin was administered one day before its removal. Ejaculates from a suffolk ram were diluted with a Tris-based extender containing either 15% (v/v) egg yolk or 10% (w/v) BSA, and the diluted semen was frozen in 0.25 ml straws. A fixed-time intrauterine artificial insemination (AI) was performed 43-47 h after CIDR removal, regardless of incidence of estrus. There was no significant difference in pregnancy rates at 60 days after AI between the extenders containing egg yolk (66.7%, 20/30 animals) or BSA (65.5%, 19/29 animals). Furthermore, there were no significant difference in the lambing rates (66.7% and 62.1%) and prolificacy (1.25 and 1.56) between the two semen extenders. The present study indicates that a semi-defined semen extender containing 10% BSA produces fertility after intrauterine AI that is similar to that achieved with semen extender containing egg yolk. o s t s e m e n e x t e n d e r s f o r f r e e z i n g o f spermatozoa, including ram semen contain egg yolk, milk, or a combination of the two as a basic ingredient. Although egg yolk is beneficial for sperm cryopreservation because it protects a g a i n s t c o l d s h o c k [ 1 ] , t h e r e a r e s e v e r a l disadvantages of addition of egg yolk to semen extender. Preparation of uniform semen extenders containing egg yolk is difficult because individual egg yolk quality may vary depending on the number of days after laying and the storage period. Furthermore, addition of egg yolk reduces the acrosome integrity of goat spermatozoa [2], and high egg yolk concentrations reduce the postthawing viability of ejaculated spermatozoa in several species, such as goats [3], rams [4] and water buffaloes [5]. Finally, development of a chemically defined semen extender would be required in order to eliminate possible infectious origins from egg yolk added to the semen extender. Several investigations have been conducted for development of semen extenders that do not contain egg yolk, such as a defined extender containing soybean lecithin for bovine and wild gazelle semen [6][7][8][9][10], and bovine serum albumin (BSA) has also been used as a substitute of egg yolk for rainbow trout and turkey spermatozoa [11,12].

Effects of Semen Extenders and Storage Temperatures on Characteristics of Frozen-Thawed Bryde's (Balaenoptera edeni) Whale Spermatozoa

“…The semen extenders were; AndroMed [6,7] and two Tris-based extenders containing 297.58 mM Tris, 96.32 mM citric acid, 82.66 mM fructose, 5% (v/ v) glycerol and either 15% (v/v) egg yolk [6,9] or 10% (w/v) BSA [6,8,10]. The three semen extenders have been defined here as AM, BSA and EY for the AndroMed, Tris-based BSA-containing and Tris-based egg yolk-containing solutions, respectively.…”

“…Our recent studies [6][7][8] on artificial insemination (AI) in sheep have clearly shown that a soybean-based semen extender (AndroMed) is useful and comparable to the conventional semen extenders containing egg yolk or BSA. Fukui et al [6] compared the fertility of ewes inseminated intrauterinally with frozen semen using AndroMed (AM) and Tris-based extenders containing BSA or egg yolk and found similar lambing rates among the three semen extenders (56.7, 55.2 and 64.5% for AM and semen extenders containing BSA or egg yolk, respectively).…”

Fertility after Artificial Insemination Using a Soybean-Based Semen Extender in Sheep

“…A soybean lecithin-based extender (AndroMed; Minitub, Tiefenbach, Germany) has been developed and utilized for bovine [7][8][9] and mountain gazelle semen [10]. Fresh and frozen ram semen diluted with a synthetic semen extender, AndroMed, has been inseminated with satisfactory fertility results in Norway (Paulenz H.: personal communication).Low fertility (20-30%) in ewes inseminated with frozen semen into the cervical orifice, an ordinal deposition site for artificial insemination (AI) in sheep, has not been applied fully on the field, except for intrauterine AI using laparoscopy (60-80% in lambing rates) [11][12][13][14][15]. In Norway, Paulenz et al [16,17] inseminated frozen ram semen into either the cervical orifice or deep vagina and obtained a lambing rate of 70%.…”

“…Half the volume of each insemination dose (0.2 ml) was deposited into each uterine horn using an insemination pipette (No. 20887; I.M.V., Rue Clémenceau, France) with the aid of laparoscopy [11][12][13][14][15].Pregnancy was diagnosed 60 days after AI by real-time ultrasonic scan. Lambing rate (number of ewes lambed/number of ewes inseminated) and prolificacy (number of lambs born/number of ewes lambed) were recorded.…”

Management Factors Affecting Fertility in Sheep

“…Ewe breed is also a significant source of variation in fertility after AI (Donovan, et al, 2004;Fukui, et al, 2007;Papadopoulos, et al, 2005;Salamon & Maxwell, 1995). Differences in the mean time of ovulation and ovulation rates in different breeds of ewes at differences locations may explain the variation in fertility (Salamon & Maxwell, 1995).…”