How is the reproductive performance of cattle? 

    Livestock reproduction is one of the most important factors in livestock cultivation activities, especially beef cattle, a good reproductive rate greatly affects the productivity of cattle to produce calves.

what are the things that affect the reproductive performance of cattle?

    Productivity is the yield obtained from an animal at a certain time. Beef cattle productivity is usually expressed as a function of the rate of reproduction and growth. The production aspect of a livestock cannot be separated from the reproduction of the livestock concerned, so it can be said that without reproduction there will be no production. It was also explained that the level and efficiency of livestock production is limited by the level and efficiency of their reproduction. Reproductive productivity can be increased if the estrus cycle and estrus schedule are observed and recorded properly.

    The estrus cycle is divided into two phases, namely the follicular phase and the luteal phase. The follicular phase is the formation of the follicle until it matures, while the luteal phase is the phase of ovulation, then the formation of the corpus luteum (CL) and until the start of the estrus cycle. The estrus cycle consists of 4 phases, namely estrus, metestrus, diestrus, and proestrus. A cow's oestrus lasts approximately 18 hours with an average estrus cycle of 21 days, while ovulation (when the egg is released from the nest) occurs approximately 12 hours after the estrus process ends. It is estimated that male reproductive sperm can live in female reproductive organs for approximately 30 hours, therefore male sperm must be ready for 6 hours before fertilization occurs. The most appropriate time to mate cattle is 10 hours after estrus takes place and 6 hours before estrus ends.

what is the estrus cycle in cattle?

    Reproductive performance is a parameter that can indicate the reproductive activity of an animal in this case is running well or not. The success factors of IB in reproductive performance that are important include Service Per Conception (S/C), Days Open (DO), Calving Interval (CI) and Conception Rate (CR). The reproductive performance will produce good quality tillers to increase livestock population. Good reproductive performance will result in good livestock productivity as well. Good reproductive performance can be achieved by taking into account the factors that can affect reproductive performance, both internal and external factors.

Service per Conception (S/C)

    Service Per Conception (S/C) is the number of marriages or artificial insemination carried out until the cattle are pregnant. The normal range of S/C in cattle is 1.6 – 2 times, the smaller the S/C value, the higher the level of reproductive efficiency, on the contrary if the S/C value is high, the level of reproductive efficiency is low. The ideal calving interval for cows is one calf in a year. A high S/C number also indicates a longer calving distance and causes a lot of losses because farmers have to pay more for IB fees and wait longer. Service per Conception is defined as the average number of natural or artificial services required for fertilization. Determining the number of Services per Conception is a simple and mostly practiced criterion of expressing fertility and analyzing costs. The causes of the high S/C include, among others, that breeders are late in detecting estrus or reporting late to the inseminator, there are abnormalities in cow reproduction, lack of skilled inseminators, facilities limited services and lack of smooth transportation The lower the value of S/C, the higher the fertility of the female livestock in the group, on the contrary, the higher the value of S/C, the lower the value of the fertility of the female group. The high reproductive fertility of female cows in the study area is supported by good maintenance management, including proper estrus detection, adlibitum feeding and sanitation carried out an average of 2.3-2.5 times a day.

Days Open (DO)

    Days open is the time interval since the cow breeds from giving birth to mating again so that pregnancy occurs. The ideal days open value is 85-115 days. Days open that occurs long enough can affect the reproductive performance of the livestock which results in long calving intervals and causes losses to farmers. the mother cow can give birth every year, the cattle must be able to become pregnant within 90 days post partum. Days open or long empty is the time interval between giving birth to pregnancy again. The ideal days open value is 85-115 days. days open can be reduced by increasing the efficiency of estrus detection, so that cattle in heat can be bred on time so as to increase the percentage of pregnancy. Days open value of local cattle is better than exotic crossbreed, which is 115±15 and 121±17, respectively. Days open local cattle and exotic cattle are 115 and 121 days, these values ​​indicate that the long days open value, the length of days open is caused by several factors, one of which is the length of time for weaning calves.

Calving Interval (CI)

    The Calving interval is the length of time or interval between births from one birth to the next. CI is an important parameter in reproduction that needs to be considered by breeders, this is because it involves the birth of calves. The ideal CI range is 12 to 15 months. The average calving interval (CI) for cows mated with the IB technique is 259.6 days or almost 12 months. The minimum CI value is 338 days and the maximum value is 377 days. If it is more than the maximum value, the farmer suffers a loss. Long birth and mating intervals (days open) occur when the offspring are not weaned so that the first post-partum oestrus takes a long time, breeders mate their mothers after giving birth for a long period of time so that the days open become long, the high failure rate of artificial insemination so that the S/C becomes tall, age at first mated late. The Calving interval (CI) is the distance between one calf birth and another. Evaluation of IB results by means of pregnancy checks is closely related to efforts to shorten the calving distance. Spacing is one of the factors that determine business efficiency. Prolonged calving in Indonesia is one of the main problems in efforts to increase the livestock population. Pregnancy diagnosis and efforts to determine the reproductive status of cows after marriage are very appropriate things to do to shorten the calving distance. The ideal CI distance is 12 months, which means that under these conditions, 85 days of vacancy are obtained and the average length of pregnancy is 278 days or approximately 9 months. A long DO will affect the CI so that it can cause economic losses for farmers due to increased maintenance costs.


Conception Rate (CR)

    Conception Rate is the percentage of pregnant cows in the first insemination which is also known as pregnancy rate. The ability of female cows to get pregnant in the first insemination is strongly influenced by environmental variations. Feed nutrition, for example, can have an effect on CR. The value of CR is shown in percentage units, the higher the percentage obtained indicates that there are quite a lot of pregnant cattle in the first marriage and indicates the AI ​​process is going well. The ideal CR value is 60%, if the CR value is still below 60%, it means that the number of pregnant cows after the first marriage is small and can cause the expected reproductive performance to not be achieved and cause losses for farmers. Conception rate (CR) was estimated from the proportion of pregnancies confirmed by rectal palpation of the genital tract at 60-90 days post-insemination among the total number of cows or heifers artificially inseminated with frozen semen for a specified time period. Feed nutrients received by cows before and after calving also affect CR, because lack of nutrients before giving birth can cause delays in the estrus cycle. 

    Conception Rate (CR) is the number of acceptors who are pregnant in the first IB divided by all acceptors multiplied by 100%. A good CR value reaches 60-70%. CR has a relationship with the value of S/C and Net Reproductive Rate (NRR). If there is a high CR value, the S/C value is low and the NRR is high. The CR value is determined by male fertility, female fertility, and insemination techniques. The level of CR is influenced by livestock conditions, estrus detection, estrus detection and reproductive management which will affect livestock fertility and conception value.

how is the reproductive performance of various breeds of cattle?