Efficiency of Previously used CIDR Stored for a Prolonged Period

Abstract

| This study investigated the efficiency of the previously used controlled internal drug release (CIDR) stored for 30 days before reusing. In the first experiment, twenty seven Holstein cows at the day of estrus (day 0) received either no treatment (control), new or reused CIDR and blood samples were collected at day 0, 1, 3 and 7. At day 1 and 3, serum progesterone concentration in cows received new CIDR (1.417 and 1.616 ng/ml) was significantly higher than in cows received a reused one (0.545 and 0.954 ng/ml) which in turn was higher than the control group. In the second experiment, estrous cycle was synchronized using Ovsynch, New-CIDRsynch or Reused-CIDRsynch. Cows in Ovsynch (n=119) received GnRH on day 0 then PGF2α on day 7. Fifty six hours after the PGF2α cows received another dose from GnRH and inseminated 18 h latter. Cows in new-CIDRsynch (n=870) and reused-CIDRsynch (n=220) were treated in the same way with exception of inserting a new or reused CIDR between day 0 and day 7. Non returned cows were examined for pregnancy diagnosis at 30 and 70 days post-insemination. Pregnancy-30 and 70 rates after New-CIDRsynch (36.1% and 30.5%) and Reused-CIDRsynch (36.4% and 31.8%) tended to be higher than after Ovsynch (27.7% and 25.2%) (P= 0.07: 0.08). In conclusion, the previously used CIDR -stored for 30 days-have residual progesterone and incorporating new or reused CIDR into Ovsynch improved the efficiency of the protocol in a similar way.

Efficacy of repeatedly used CIDR device in cattle reproduction: a metaanalysisreview of progesterone concentration and conception rate

“…The standard approach to evaluate blood P 4 concentration is to include ovariectomized cows and/or intact cows in estrus as the basis (18). As the number of usages of the CIDR devices increased, delivered blood P4 concentrations linearly decreased, especially after the 2nd use ( Table 2).…”

“…P 4 concentrations. More specifically, the absorbability of P 4 may also vary by the estrus cycle stage due to alterations in the vaginal membrane (18). Interrelationships among body weight, feed intake, and milk yield, leading to alterations in hepatic blood flow and steroidal hormone metabolism, are well established (3,18).…”

Effect of synchronization protocols on reproductive indices, progesterone profile and fertility under subtropical environmental conditions in repeat breeder Holstein cows

“…The current trial estimated no significant difference in embryonic loss rate between the Ovsynch and both CIDR‐based protocols. Others recorded a similar embryonic loss rate between the CIDRsynch and Ovsynch protocols in cyclic or anovulatory cows (Abdallah & Abd El Rahim, ). On the contrary, previous trials indicated that embryonic loss rates using the CIDRsynch were significantly lower than those reported with the Ovsynch protocol in anovular cows (Chebel et al, ).…”

Manipulation of Fertility in Crossbred Dairy Cattle Using Controlled Internal Drug Release Device Combined With Prostaglandin and Equine Chorionic Gonadotrophin

“…In anestrus cattle, the cost of this estrus synchronization protocol can be further reduced to US $14.57, as PGF2α is not necessary in the absence of CL. Additionally, the prospect of reusing a used CIDR device [60] makes the protocol worthwhile.…”