2 Principle, Benefit, Criteria for Controlled Breeding

Transcript

Greetings to all!

Principle:

Today in this class we are going to see the basic principle and approaches of Estrous Synchronization in cows and buffalos. What is Estrous Synchronization- Bringing a group of animals into Estrous at a predetermined time by using an exogenous hormone. The very important thing is “predetermined time”, suppose if you have a hundred non-pruned animals, all the hundred non-pruned animals can be brought into estrous at a particular time, this is called Estrous Synchronization. So, the very important thing is, the improper Estrous Reduction and Untimely Insemination is the major cause of infertility in the field. That is why if you know this – Estrous Synchronization, it is very easy to tackle the infertility problem. The basic principle is the regulation of the lifespan of the Corpus Luteum (CL). There are two approaches available for Estrous Synchronization-one is shortening the luteal phase by using PGF2 Alpha and another one is extending the luteal phase by using Progesterone. So, these are the two fundamental approaches available for the Estrous Synchronization Program -one is shortening the luteal phase by using PGF2 Alpha or Prostaglandin F2 alpha another one is extending the luteal phase by using Progestational preparations. Then if you take the Estrous Synchronization protocols 1) Prostaglandin based protocol 2) Progesterone based protocol and 3) GnRH based protocol. So, by using these three protocols we can manipulate the Estrous cycle of cows and buffalos to achieve a high consumption rate.

Benefit:

What are the benefits of Estrous Synchronization?

Advantages:

If you know the uses, you can use the Technology very well. So fundamentally, it is used for better control of calving intervals. You can reduce the consumption to calving interval, thereby you can produce a calf per year with the use of this important technology. So, you can reduce the calving interval, so the inter calving period can be reduced. Once if you synchronize the Estrous and do on many numbers of AIs similarly, a group of females will calve simultaneously. All the animals’ calves in a particular period, so Maintenance of cows and Vaccination program, Management procedures are very easy by using this technology. It reduces the time required for Estrous reduction. When you do an Estrous Synchronization program, it is otherwise called Controlled Breeding or Fixed Time Breeding or Programmed Breeding. So, you can program the Breeding. So thereby you can avoid the labor involved in the Estrous Reduction program. And many times, in villages animals will be in a particular site and the owner will be having his home two kilometers or three kilometers away from the animal shed in the Indian scenario, so they may not detect the Estrous properly. They are not with the animals during the night hours, most of the animals are coming to heat during the cooler part of the day, that is during night hours and early morning. So, since owners are staying away from the animal shed, they cannot detect the Estrous that may lead to infertility problems. So, such types of problems can be avoided by the Estrous Synchronization Program. Then you can do Estrous detection with Timed Artificial Insemination, which will save the time required for Estrous Reduction. From which you can increase the production. Particularly, suppose in the month of summer, there will be a reduction in the milk yield from many animals. But if you want to have more calving peak milk yield at that time, you can program breeding based on this Estrous Synchronization program. So, since we are reducing the consumption to calving interval and in the calving interval number of cows produced per cow in its lifetime can be increased with this important technology. Then, Infertility- Estrous Synchronization is not only a management tool but also it is helpful to Alleviate or Treat or Manage the infertility problems under field condition. So, these are all the benefits of the Estrous Synchronization program in cows and buffalos.

Criteria:

For Controlled Breeding or Fixed Time Breeding or Programmed Breeding or Estrous Synchronization or Estrous Induction. You must know the difference between Estrous Induction and what is Estrous Synchronization. In India, particularly in Tamil Nadu and other places, owners owning one or two cows are more than the Farming system. The Farming system is not common in the Southern part of India, so owners will be owning one or two animals. You can’t do synchronization in one animal or two animals. If you induce Estrous in many animals or hundreds of animals, it is called Estrous Synchronization. If you induce Estrous in a single animal, it is called the Estrous Induction program. So, the Estrous Induction and Synchronization program requires all these requirements.

Animal requirement:

You cannot do this program on a sick, debilitated, and weak animal. Even if you do this program, you cannot achieve the success of fertility, so animals must be disease-free animals. Adequate nutrition of the body condition score must be three and four. It should not be too lean; it should not be too fat. So, animals must be in good body condition with adequate nutrition and the adequate postpartum interval. The animal should have at least passed 45 to 60 days and should not do 20 days of calving. Next to Normal Non-pregnant Reproductive Tract: It should not have Adolescence, it should not have Infections, it should not have hydrosalpinx mucosulphings, etc. So, the normal genital tract must be there, and the animal must be cycling. In case of when you use prostaglandin-based protocol animals must be cycling. So, all these are Important Criteria.

Management requirement:

Proper timing should be maintained. The proper schedule of the Estrous Synchronization program should be correctly followed. Good quality Semen must be (very very important, I am always stressing this one) used. When you do Estrous Synchronization program in hundreds of animals or infertile animals, the Semen must be of a good quality You should do AI (Artificial Insemination) perfectly, good AI techniques must be followed otherwise the program will be a failure. When you use the Prostaglandin-based protocol, it will act only in the functional CL, that is it will act on days 6 to 16 of the cycle only. So, always you should have Matured Corpus Luteum on the Ovary, either the Right Ovary or Left Ovary should have Matured Corpus Luteum. Developing CL or Regressing CL will not respond to PGF2 Alpha. So, this is what we wanted to say. When there is a Developing CL from day zero to six that is three days of Metestrum and three days of Diestrum there is a Developing CL, that CL will not respond to PGF2 Alpha. Even if you give PGF2 alpha CL will not Regress instead it will grow. And what is Regressing CL, at the end of Diestrum, when it enters into the proestrus stage it will be a Regressing CL-that CL also will not respond to. So, during proestrus or Estrous and Metetrous and early Diestrous, you should not use PGF2 Alpha. There is no harm if you use PGF2 Alpha, but it will not produce the proper effect. So, one thing you should remember regressing Cl that is during proestrus or developing CL will not respond to PGF2 Alpha therapy. Only matured CL will respond to PGF2 Alpha therapy. When matured CL will be there from day 6 to 16th day of the Estrous cycle, the matured corpus luteum will be there, so you can use PGF2 alpha during this time to synchronize or to induce Estrous.

Examples:

These are some of the examples as a Field Veterinarian what are all the Commercial Preparations available, these are all Synthetic Prostaglandins:

Vetmate is available

Clostenolis available

Pragma is available

PGF2 Alpha available

This dose of each ml contains 250 micrograms, so 2ml we will give Intramuscularly, 500 micrograms synthetic prostaglandin will be administered. Whereas natural prostaglandin, 25 milligrams will be administered Intramuscularly. It is only the total dose, not per kg, it is only the total dose. Remember 500 micrograms total doses intramuscularly synthetic prostaglandins like Pragma, Clostenol, or Vetmate or Estrumate. If it is natural, prostaglandin utilizes 25 milligram 5ml Intramuscularly.

Dear friends, so far, we have seen about

The Principles of Estrous Synchronization.

Protocols of Estrous Synchronization.

Benefits, Animal requirement and Management requirement

Following the Prostaglandin method of Estrous Synchronization

To understand these procedures, we will continue the class about the Follicular wave pattern in cattle.

Thank You!