AT THE TIME OF INSEMINATION AS A METHOD FOR ELIMINATING TWIN PREGNANCIES IN DAIRY CATTLE
Twin pregnancies are one of the most important factors affecting the finances of dairy cattle farms as they have a high rate of pregnancy loss compared with single pregnancies, and, if twins are born, the indirect costs increase dramatically. Among others, the animal elimination rate increases (reducing the average life of the animal at the farm) as does expenditure on anti-inflammatory and antibiotic drugs to reduce postpartum illnesses.
For this reason, attempts are being made worldwide to implement different techniques to reduce the associated negative impacts, such as the manual rupture of one of the amniotic vesicles during the 28-41 days following artificial insemination (AI), or an ultrasound-guided technique of follicular drainage of one of the two follicles present at the time of AI. Although both techniques work acceptably well, the former increases pregnancy loss possibly due to the placental anastomoses of this species. However, the technique of ultrasound-guided follicular puncture reduces twin pregnancies and increases additional corpora lutea (CL), but cannot be carried out at the rate of a weekly reproductive visit and, moreover, the material required is costly. Recently, a technique using ultrasound-guided follicular puncture has been described that can be conducted at weekly reproductive visits. It is very similar to the Ovum Pick Up but without ultrasound.
This has a very high impact on the economy of the farm, on the welfare of the animal and on reducing the use of antibiotics postpartum.
SCOPES OF APPLICATION
Intensively husbanded dairy or beef cattle.
Can be performed by any technician but the minimum requirements are:
Experience in rectal palpation
Anatomical knowledge of the cow’s reproductive apparatus
Does not require anaesthesia
Rapid procedure (experienced technician)
High fertility rate
Reduces twin pregnancies to 0
OF THE TECHNIQUE
STEPS TO BE TAKEN
DESCRIPTION OF THE TECHNIQUE
The technique consists of follicular puncture without suction of the smaller follicle on the day of AI using a rigid cannula designed for follicular cyst puncture (Minitub Ibèrica S.L., la Selva de Camp, Tarragona, Spain).
It is equally effective both in animals with bilateral and unilateral follicles.
Although fertility is statistically the same for control cows (on which the technique is not performed but two follicles are present at the time of AI), ovulatory failures increase significantly.
Currently, the proposed treatment for the animals is the application of a potent inducer of ovulation, such as hCG. Further studies are required to determine whether, in addition, the simplified technique with hCG treatment not only surpasses the fertility of the control group, but reduces pregnancy losses due to additional CL and eliminates twin pregnancies. To facilitate the function of this additional CL induced, a dose of dephereline (GnRH analogue) is administered on day 7 after puncturing.
IT CAN BE PERFORMED AT THE REPRODUCTIVE VISIT
STEPS TO BE TAKEN
.1 Detect follicles by ultrasound on day of AI
.2 Clean the vulva using water with iodine
.3 Insert the rigid cannula via the vulva as far as the fornix
.4 With the other hand, guide the ovary to the fornix
.5 Puncture without sucking the small follicle
.7 At the moment of AI, administer an inducer of ovulation (GnRH, dephereline, hCG)
.8 On day 7, administer an inducer of ovulation (GnRH, dephereline)
PICTURES AND VIDEOS
The technique reduces twin pregnancies to 0
It can be performed both in bilateral and unilateral follicles
Subsequent fertility is similar to the farm average
The administration of an inducer of ovulation is required at the time of AI
Número de fol·licles
Estrés per calor (>72 u THI)
Pèrdues de gestació***
No (n = 144)
3 (2.1 %)
Si (n = 145)
No (n = 69)
Si (n = 45)
No (n = 69)
Si (n = 44)
* of the smaller follicle
** in animals with two follicles upon AI: for all follicles of the group without drainage and for undrained follicles of the group with drainage.
*** of pregnant cows.
Irina Garcia-Ispierto holds a PhD from the University of Barcelona (2008). She is currently a contracted professor at the Department of Animal Science at the University of Lleida and head of research of the Animal Reproduction Group at the Agrotecnio Research Centre. Her research focuses on the reproduction of dairy cattle. Her specialities are twin pregnancies, synchronization methods, reproductive ultrasound, and fertility problems. She has also studied infections such as Coxiella burnetti and parasites such as Neospora caninum.
She has published over 100 articles in indexed journals and has taken part in over 100 conferences, both national and international. She has participated in symposiums organized by companies such as ECUPHAR and Ceva and has written several articles in general interest magazines.
Articles in scientific journals
López-Gatius, Fernando and Garcia-Ispierto, Irina. 2020. Tranfer of a single embryo versus drainage of subordinate follicles to prevent twin pregnàncies in dairy cows. Why not both? Journal of Reproduction and Development, Advanced Epub April 7, 2020.
López-Gatius, Fernando; Garcia-Isperto, Irina; Serrano-Pérez, Beatriz; Balogh, Orsolya G.; Gábor, György and Hunter, Ronald H. F. 2019. Luteal activity following follicular drainage of subordinate follicles for twin pregnancy prevention in bi-ovular dairy cows. Research in Veterinary Science, 124: 439-443.
Articles in professional journals
Garcia-Ispierto, Irina. 2020. Prevención de las gestaciones gemelares en vacuno lechero: un camino hacia la innovación. Albéitar, 234: 4-6.