THE ROLE OF HORMONE LEPTIN FOR HANDLING REPRODUCTIVE CASE IN BALI CATTLE

Bali Province is one of the beef cattle supplier regions for national meat needs. Seeing the considerable needs and to improve food security by optimally providing beef, various anticipatory steps need to be taken, for example with the development of Bali cattle. Development can be done with a technical approach and economic approach. The technical approach is carried out by increasing livestock production and productivity, through increasing births, suppressing mortality, preventing slaughtering productive female cows, improving artificial insemination technology (IB), and improving genetic quality and animal health services. The economic approach can be carried out with an integrated agribusiness approach from upstream, namely by breeding cattle to produce broodstock, on-farm segments in the form of aquaculture and fattening activities that use local feed with the application of technology so as to increase weaning weight according to its genetic potential.

Specifically regarding the reproductive performance of Bali cattle, efforts that need to be made are (1) increasing the conception rates, (2) shortening calving intervals, (3) reducing calf mortality, (4) preventing slaughtering productive female cows and (5) began to apply reproductive biotechnology to bali cattle. In order to maintain the balance of the cattle population of Bali cattle has been issued Regional Regulation (Perda) No. 2 of 2003 concerning the expenditure of bali beef cattle. The operational technical implementation is determined through a Governor Regulation which regulates the Determination of the Number of Inter-Island Bali Beef Cattle issued annually

Bali cattle is one of the genetic resources of native Indonesian cattle. Bali cattle are the domestication of wild sondaicus Bosses whose natural habitat is on the island of Bali. The specific phenotypic form of a bali cow is a medium size, deep chest, slender legs, brick red skin, nose mirror, nails and tail tip feathers that are black. The feet under the carpal and tarsal joints are white. White skin is also found on the buttocks that are oval (white mirror). At the top of the back always found black hair forming a line (eel line).

Some of the advantages possessed by Balinese cattle when compared with other Indonesian local cows are able to produce good quality meat and carcass with a higher percentage of carcasses. A high percentage of carcass production can reach 60%, making it suitable to be developed as beef cattle. The quality of feed really determines the quality of Bali beef.

Bali cattle have advantages compared to other local cattle, because they have high fertility up to 90%, pregnancy rate 80-90%, high birth rate (more than 80%). In addition, the percentage of Balinese cow carcass is quite high (56%), the fat contains low cholesterol with high growth compensation.

But Bali cattle also have a weakness that is the length of the breeding distance due to the absence of heat more than 3 months after giving birth. Ideally, the distance between calves is no more than 365 days or 12 months to give birth to one child in a year. Low food intake before and after birth will increase the distance from childbirth until the appearance of the next heat cycle.

The return of the heat cycle after delivery is highly dependent on the function of the ovarian pituitary hipothalamus shaft. The increase in the frequency of GnRH produced by the hypothalamus is a major factor in increasing circulating FSH, LH from the anterior pituitary. Increased FSH and LH will be followed by the development of follicles in the ovaries where the follicles will synthesize and produce the hormone estrogen. Leptin is one of the metabolic signals that regulates the axis of the ovarian pituitary hipothalamus.

Considering the occurrence of reproductive cases that is not the appearance of lust after giving birth can reduce reproductive performance and the number of child births every year so that the administration of the hormone leptin in bali cows who experience a case of not arising after giving birth can increase levels of endogenous leptin, FSH, LH, estrogen and the development of ovarian follicles .

Leptin in the blood is highly correlated with the accumulation of the amount of adipose tissue. Reduced nutrition will reduce the level of adipose tissue in cows. In ruminants, circulating leptin concentrations are positively correlated with obesity. Leptin secretion is regulated in the short, medium and long term by food intake, nutrition and hormones, energy balance, obesity and animal nutrition history.

That the decrease in the LH hormone by limited nutrition is inversely proportional to the administration of leptin. This indicates a positive relationship between the LH hormone and leptin. The effect of leptin on the LH hormone during puberty development in pigs is associated with the stage of sexual maturation and changes in the negative feedback of the hormone estrogen on the body.