What exactly is a CIDR, and how does it affect your herd?
What is CIDR?
CIDR stands for Controlled Internal Drug Release. It is a device that is used in cattle breeding to regulate the reproductive cycle of cows. CIDR is a T-shaped device with flexible wings that collapse to form a rod for insertion into the vagina. A tail is attached for easy removal. The CIDR's nylon spine is covered with a progesterone-impregnated silicone skin, which suppresses the cow’s natural estrus cycle.
CIDR is an intravaginal progesterone insert used in conjunction with hormones to synchronize estrus in female cattle. Developed in New Zealand, CIDRs are a viable alternative for producers with one or more of the following breeding challenges:
inefficient heat detection,
non-cycling cows with poor response to breeding programs,
cows and heifers in the wrong stage of their estrus cycles to initiate breeding, or
heifers that aren't cycling, even if old enough to do so.
How does CIDR work?
CIDR devices are typically used in combination with other reproductive technologies, such as artificial insemination or embryo transfer. By controlling the cow’s estrus cycle, producers can synchronize the breeding of their herd. This helps to optimize the use of resources, such as labor and semen, and improves the overall efficiency of the breeding program.
A CIDR is inserted for seven days which causes the animal's blood progesterone concentrations to rise rapidly, with maximum concentrations reached within an hour after insertion. Progesterone concentrations are maintained at a relatively constant level during the next seven days. Upon removal, progesterone concentrations are quickly eliminated. Because the CIDR's retention rate can exceed 97% over the seven-day period, producers needn't worry about the device falling out.
Benefits of using CIDR
There are several benefits to using CIDR in cattle breeding. First and foremost, it allows producers to synchronize the breeding of their herd, which can help to improve the overall efficiency of the breeding program. It also allows producers to plan the calving season, which can help to optimize the use of resources and reduce labor costs. Additionally, CIDR can be used to induce estrus in cows that have not been cycling regularly, which can help to improve fertility rates.
How to use CIDR
CIDR devices are typically used in combination with other reproductive technologies, such as artificial insemination or embryo transfer. Before using CIDR, producers should consult with their veterinarian to determine the appropriate protocol for their herd. The device is typically inserted into the vagina of the cow for a period of 7 to 12 days, after which it is removed. The cow is then either artificially inseminated or transferred with embryos.
Fixed time AI
CIDR's greatest advantage is to facilitate fixed-time AI, where no estrus detection is necessary. The protocol is simple, yet subtly different for cows and heifers:
For all females, the CIDR is inserted at the same time as GnRH (Cystorelin, Frtiline, etc.) is injected. Seven days later, the CIDR is removed and the cow receives a prostaglandinF2 injection (such as Estrumate or Cloprostenol).
In cows, perform AI at 63+3 hours after CIDR removal, and administer a second GnRH injection. In heifers, however, the interval between CIDR removal and AI with a second GnRH injection 54 hours after. Overall pregnancy rates should exceed 55% of all cows synchronized, which is generally better than any heat detection protocol.
To achieve optimal pregnancy rates with CIDR-based ES protocol, females should be in good body condition — usually a 5 or better — and treatments should be initiated only when cows are at least 45 days post-calving.
Side effects of using CIDR
While CIDR is generally considered safe and effective, there are some potential side effects that producers should be aware of. These include vaginal discharge, inflammation, and infection. It is important to follow the manufacturer’s instructions carefully and to consult with a veterinarian if any issues arise.
Conclusion
CIDR is a valuable tool in cattle breeding that allows producers to synchronize the breeding of their herd, optimize the use of resources, and improve the overall efficiency of their breeding program. While there are some potential side effects to using CIDR, these can be minimized by following the manufacturer’s instructions carefully and consulting with a veterinarian. By using CIDR in combination with other reproductive technologies, producers can help to maximize the productivity and profitability of their herd.
