Reproductive performance of the largest captive Asian elephant (Elephas maximus) population in Sri Lanka.

The Pinnawela Elephant Orphanage (PEO) in Sri Lanka maintains one of the largest captive Asian elephant (Elephas maximus maximus) populations in the world, with a total of 79 animals (45 females and 34 males) at present. It was established in 1975 as an orphanage for rescued wild calves, and commenced natural breeding under controlled conditions when they reached breeding age. This study summarizes reproductive data of 65 live births from 38 years of records at PEO. The age at first calving (n=31) was 14.6±0.7years, and the numbers of females giving birth two, three, four and five times were 21, 8, 4 and 2, with corresponding inter-birth intervals (IBI) of 4.9±0.3, 4.8±0.5, 7.9±1.9 and 5.7±0.5years, respectively. Females giving birth to males (5.7±2.2years) had longer IBIs compared to birthing female calves (4.7±1.1years). The average gestation for 18 pregnancies with known conception dates was 667±11days. The average birth weight was similar for male (83.1±4.6kg; n=14) and female (82.8±8.4kg; n=6) calves. Sex ratio for live births was 36 male:29 female and not different from 1:1; however, more males (10/14) were born after a second parity. Calf mortality and stillbirth rates were low: 7.6% and 4.4%, respectively. This study highlights the successful breeding program at the PEO, providing baseline reproductive data that can aid in improving breeding of other elephants managed under captive conditions.

Reproductive cycles of buffalo.

The domestic water buffalo (Bubalus bubalis) has an important role in the agricultural economy of many developing countries in Asia, providing milk, meat and draught power. It is also used in some Mediterranean and Latin American countries as a source of milk and meat for specialized markets. Although the buffalo can adapt to harsh environments and live on poor quality forage, reproductive efficiency is often compromised by such conditions, resulting in late sexual maturity, long postpartum anoestrus, poor expression of oestrus, poor conception rates and long calving intervals. The age at puberty is influenced by genotype, nutrition, management and climate, and under favourable conditions occurs at 15-18 months in river buffalo and 21-24 months in swamp buffalo. The ovaries are smaller than in cattle and contain fewer primordial follicles. Buffalo are capable of breeding throughout the year, but in many countries a seasonal pattern of ovarian activity occurs. This is attributed in tropical regions to changes in rainfall resulting in feed availability or to temperature stress resulting in elevated prolactin secretion, and in temperate regions to changes in photoperiod and melatonin secretion. The mean length of the oestrous cycle is 21 days, with greater variation than observed in cattle. The signs of oestrus in buffalo are less overt than in cattle and homosexual behaviour between females is rare. The duration of oestrus is 5-27 h, with ovulation occurring 24-48 h (mean 34 h) after the onset of oestrus. The hormonal changes occurring in peripheral circulation are similar to those observed in cattle, but the peak concentrations of progesterone and oestradiol-17ß are less. The number of follicular waves during an oestrous cycle varies from one to three and influences the length of the luteal phase as well as the inter-ovulatory interval. Under optimal conditions, dairy types managed with limited or no suckling resume oestrus cyclicity by 30-60 days after calving, while swamp types with free suckling do so at 60-90 days. However, in many farming systems prolonged postpartum anoestrus is a major problem, and the causes include poor nutrition and body condition, and stress due to harsh climates and improper management. Synchronization of time or induction of oestrus can be done using the same regimens as applied in cattle, using various combinations of prostaglandins, progesterone releasing devices, GnRH and eCG, but success rate is poor when treatment is done during the periods of marginal breeding activity or seasonal anoestrus.

Reproduction in domestic buffalo.

The domestic buffalo is an indispensable livestock resource to millions of smallholder farmers in developing countries, particularly in Asia. Although its reproductive biology is basically similar to that of cattle, there are important differences and unique characteristics that need to be considered in order to apply modern reproductive technologies to improve its productivity. Under most smallholder production systems, the reproductive efficiency of buffalo is compromised by factors related to climate, management, nutrition and diseases. However, when managed and fed properly, buffalo can have good fertility and provide milk, calves and draught power over a long productive life. The basic technical problems associated with artificial insemination in buffalo were largely overcome two decades ago, but the technology has not had the expected impact in some developing countries, because largely of infrastructural and logistic problems. Approaches involving the use of hormones for treating anoestrus and for synchronizing oestrus have had varying rates of success, depending on the protocols used and the incidence of underlying problems that cause infertility. Embryo technologies such as multiple ovulation embryo transfer, in vitro embryo production, cryopreservation and cloning are being intensively studied but have had far lower success rates than in cattle. Improving the productivity of buffalo requires an understanding of their potential and limitations under each farming system, development of simple intervention strategies to ameliorate deficiencies in management, nutrition and healthcare, followed by judicious application of reproductive technologies that are sustainable with the resources available to buffalo farmers.

Validation of a human progesterone enzyme immunoassay (EIA) kit for use on serum of cattle in Cameroon.

A study aimed at validating a human progesterone enzyme immunoassay kit was carried out on cattle at Bambui, Cameroon. Progesterone ELISA Kits (EH-511) were obtained from Clinpro International. Forty-one cows were selected, of which 19 were pregnant and 22 within 14 days post partum. Blood samples were analysed and progesterone levels were deduced from a curve obtained from standard absorbance values (A450). Results show that 95.5% of postpartum cows had progesterone levels below 1 ng/ ml, with the highest level being 0.75 ng/ml. The mean level was 0.5 +/- 0.26 ng/ml. The cows in the 'pregnant group' had progesterone levels ranging from 3.5 to 17.5 ng/ml. This kit can be used for measuring progesterone levels in cattle. Levels of 1 ng/ml for two consecutive samples or one sample at or above 3 ng/ml are an indication of the presence of corpus luteum, while cows below 1 ng/ml will be in anoestrus.

A coordinated research programme to develop methodologies for an integrated approach to improve small scale market oriented dairy systems in developing countries.

A five-year Coordinated Research Project (CRP) entitled 'Integrated approach for improving small scale market oriented dairy systems' is currently being implemented by the Food and Agriculture Organization and the International Atomic Energy Agency, through their Joint Programme on 'Nuclear Techniques in Food and Agriculture'. The objectives are to (a) identify and prioritize the constraints and opportunities in the selected dairy farms; (b) determine the most important limiting factors; (c) develop intervention strategies; (c) assess the economic impact of the interventions; (d) develop methodologies for recording and demonstrating the economic impact; and (e) promote the adoption and dissemination of proven strategies and methodologies. Fifteen institutes in developing as well as developed countries are participating in the project, through ten research contracts (Bangladesh, Cameroon, Pakistan, Paraguay, Peru, South Africa, Sri Lanka, Tanzania, Tunisia and Venezuela), one technical contract (Peru) and four research agreements (Malaysia, U.K., U.S.A. and Uruguay). The initial phase of the project, which focused on the conduct of Participatory Rural Appraisals and Economic Opportunity Surveys in the countries of the research contract holders, has now been completed. This paper describes the background to the CRP approach and the procedures used for developing, initiating and implementing this project.