Female Alpacas Research Articles

A behaviour study on the potential for direct transmission of tuberculosis from possums (Trichosura vulpecula) to alpacas (Lama pacos), and the converse from alpacas to possums

Aims. To evaluate the potential for the direct transmission of tuberculosis from possums to alpacas, and vice versa. Methods. A field study was conducted on an alpaca farm in Northland, New Zealand on 7 January 1999. Observations were recorded on the interaction of one group of male alpacas with a simulated dead possum, one male and one female alpaca group with a simulated terminally tuberculous possum, and one group of male alpacas with a normal possum in an enclosure from which the animals could not escape. The possum was sedated with ketamine as hydrochloride to simulate death (inactive; no movement), and terminal illness (active, into-ordinated movement around the paddock). The observations were based on the focal animal sampling technique, they were un-replicated, and recorded visually and manually with intermittent still photography. Results. Both male and female alpacas showed strongly inquisitive interaction with the possum. They clustered around the possum (focal animal) very soon after it was observed by the first member of the group. The interest of the majority of both sex groups remained high for the observation periods of approximately 30 minutes, and most individuals remained within 5 metres of the possum for that time. Approximately 50% of the alpacas were within possible aerosol transmission distance of 2 metres from the sedated, erratically mobile possum with their heads towards it for approximately 50% of the two observation periods. Aggressive behaviour was recorded for a young male with stamping on the moving possum. Similar, but more vigorous and prolonged stamping behaviour was recorded for a female with a young (<1 week) offspring (cria).The stamping behaviour was accompanied by very close nose to nose contact of the alpaca and possum. At one point the female threw the possum approximately 1.5 metres in the air with her teeth. The group of male alpacas placed in an enclosure with an unsedated normal possum generally moved away from the possum during its rapid active attempts to escape. When it became inactive their approaches were cautious and only once elicited a defence reaction from the possum, from which they recoiled. One male made one attempt to stamp on the active possum. Soon after the possum became inactive in a small loose hay pile, the alpacas lost interest in it. Conclusions. The alpaca / possum behavioural interactions show there is potential for direct aerosol transmission of tuberculosis from possums to alpacas, but probably not from alpacas to possums.

Vitamin D doses for alpacas (Lama pacos).

To assess the effectiveness of cholecalciferol (D3) doses for maintaining adequate vitamin D status in crias and adult female alpacas at pasture. A field experiment during winter and early spring in a herd on a farm in South Australia. ANIMALS AND PROCEDURE: Crias, usually less than 6 months of age and female alpacas, aged 2 to 6 years, were given a single subcutaneous dose of 0, 1000 or 2000 IU D3/kg body weight. Plasma concentrations of 25-hydroxycholecalciferol (25-OH D3), phosphorus, calcium and vitamins A and E and alkaline phosphatase activity were measured at intervals over a period of 16 weeks after treatment. Crias not given a vitamin D supplement had reduced growth rate during winter and one animal showed clinical signs of rickets. Vitamin D treatment had no effect on the body weight of mature females. Vitamin D supplements increased the 25-OH D3 and phosphorus concentrations in plasma of both crias and adult females; alkaline phosphatase activity was not affected by treatment. It is suggested that for alpacas in southern Australia a subcutaneous dose of 1000 IU D3/kg body weight to crias in late autumn and again in mid winter and to adult females in mid winter should prevent vitamin D inadequacy.

The Effect of Short Duration Transportation on Serum Cortisol Response in Alpacas (Llama pacos)

This research project evaluated the changes in serum cortisol in six male and six female alpacas in response to transportation of short duration. All alpacas were subjected to trailer transportation for 30min. Serum samples were obtained prior to transportation, immediately after transportation, and after a 4-h recovery period. Heart rate was recorded at each time interval and observations of individual behavioural characteristics were recorded. Data were analysed using analysis of variance. Heart rate was not significantly changed by transportation stress. Serum cortisol concentration was significantly higher after transportation, but had returned to baseline concentration after the 4-h recovery period. Behavioural characteristics were not associated with changes in serum cortisol concentration.

DEGELIFICATION OF ALPACA SEMEN AND THE EFFECT OF DILUTION RATES ON ARTIFICIAL INSEMINATION OUTCOME

Degelification of highly viscous alpaca semen was attempted using two enzymes: trypsin and collagenase. Dilution effect on artificial insemination was determined in alpacas. Semen from 4 male alpacas was collected, degelified, diluted, and inseminated into 80 female alpacas. Degelification was achieved adding trypsin and collagenase enzymes to fresh semen samples. Semen was diluted with egg-yolk glucose citrate to give concentrations of 4, 8, and 12 million spermatozoa/mL. Females were induced to ovulate with human chorionic gonadotropin and then inseminated deep into the uterine horns. Analysis of variance was used to determine differences in the effect of trypsin and collagenase on sperm acrosome and on motility and live spermatozoa. The chi-square test was used to determine differences in pregnancy of artificially inseminated females. Semen was degelified with different concentrations of trypsin and collagenase. There were differences (p < .05) in the pregnancy rate of female alpacas inseminated with 4 million (53.3%), 8 million (66.7%), and 12 million sperm/mL (61.5%). Alpaca semen may be degelified using trypsin and/or collagenase. It seems that 8 million sperm/mL is adequate for artificial insemination in alpacas.

Fertility of the male alpaca: effect of daily consecutive breeding.

The fertility of the male alpaca under different frequencies of daily consecutive matings was evaluated. Fifteen adult male Huacaya alpacas were divided randomly into three groups of five each to breed lactating female alpacas. The schedule of daily matings was two, four and six consecutive breeding per group and for nine consecutive days. Ovulation was determined by progesterone at seven days after breeding. Pregnancy was determined by ultrasonography at 15 and 30 days after breeding. Two hundred and eighty females were bred with some males not fulfilling their schedule of breeding. There were differences (P < 0.05) in the fertility rate of males breeding two and four times daily (76%) in contrast to 59% for males breeding six times. There were also differences (P < 0.05) in the fertility of individual males. Length of copulation was affected (P < 0.05) by schedule of matings, day of breeding and male. Ovulation was independent of length of copulation. Overall, it seems the fertility of the male alpaca is affected significantly when consecutive matings are over four times a day and for nine consecutive days.

Collection of semen and artificial insemination of alpacas

Semen collection and artificial insemination have not yet been fully developed in the alpaca. Thus, we collected semen from 7 males suing a modified artificial vagina placed inside a dummy. Forty adult female alpacas, previously induced to ovulate with hCG, were artificially inseminated with fresh undiluted semen by laparoscopy or by cervix. The Chisquare test was used to determine differences in the fertility rate of the 2 insemination methods. The mean duration of copulation, semen volume, sperm concentration and the percentages of live spermatozoa and normal spermatozoa were 21.6 min, 1.9 ml. 147,500/mm 3, 69.6% and 75.9%, respectively. There were 6.7% abnormal heads, 12.3% abnormal tails and 3.8% cytoplasmic droplets. The consistency of semen was viscous and formed a coagulum. The pH was 7.2, and the semen was milky white in color. The duration of copulation was comparable to natural copulation, and semen characteristics reflected those of the natural ejaculate. The percentage of pregnancy was 68%, with no differences due to method of semen deposition (laparoscopy, 67%; cervix, 73%).

Photoperiodic control of the time of parturition in alpacas (Lama pacos)

Twenty-three mature female alpacas in late gestation in October (spring group) and in January (summer group), were randomly allocated to two treatments. In each season, one group was placed indoors under natural light and the other group was placed in a treatment room which could be totally blacked out to external light and had artificial lights controlled by an automatic time switch. Lights in the treatment room were switched on at 12:00 h and switched off at 02:30 h. Video cameras were used to record the times of parturition. The mean time of parturition for alpaces in the treatment room (16:43 h ± 69 min) was 6 h 23 min later (P < 0.001) than the alpacas in the control room (10:20 h ± 67 min). The mean intervals from sunrise or lights-on to parturition and from sunset or lights-off to parturition were similar for both treatment groups, and there were no effects of treatments on gestation length. The mean interval from the start of the treatments to parturition was shorter (P < 0.001) in the spring group(18 ± 2 days) than in the summer group (36 ± 2 days). In conclusion, the results showed that the time of parturition in alpacas is under photoperiodic control.

Evaluation of early reproductive performance in the postpartum alpaca by progesterone concentrations

Abstract The proportion of female alpacas ovulating, conceiving and remaining pregnant up to 40 days after copulation was evaluated using progesterone concentrations. One hundred and seventy six parous, postpartum alpacas were divided into three groups for breeding at 10, 20, and 30 days postpartum at the La Raya research station, Cusco, Peru. Females were further subdivided into three groups to allow copulation once, twice, or three times at 24-h intervals, within different postpartum times. Blood samples were collected at time of breeding, at Day 7 (ovulation), at Day 21 (conception), and Day 40 (pregnancy) from all females after breeding. Progesterone analysis was performed by enzyme immunoassay. There was significant difference in the proportion of females ovulating at Days 10 ( 40 62 ), 20 ( 40 52 ) or 30 ( 52 62 ) postpartum; however, frequency of breeding did not increase the number of females ovulating. There was significant difference in the proportion of females conceiving at Days 10 ( 25 40 ), 20 ( 35 40 ), and 30 ( 47 52 ) postpartum, compared with females ovulating at the three times of breeding. There was also a significant difference in the number of females in which pregnancy was sustained at Day 40 when bred at 10 (19), 20 (31) and 30 (44) days postpartum. There were significant differences in the concentration of progesterone of ovulating females (4.2 ng ml −1 ), conceiving females (3.1 ng ml −1 ) and females remaining pregnant (1.4 ng ml −1 ), compared with the overall mean of 0.4 ng ml −1 for females that did not ovulate, did not conceive and that experienced embryonic mortality. Altogether, these results suggest that breeding as early as Day 10 postpartum does not yield acceptable fertility rates as compared with breeding on Days 20 or 30 postpartum, and that repeated breeding does not increase the number of females ovulating or conceiving.

Seasonal and other factors affecting the sexual behaviour of alpacas

Records of sexual behaviour of 13 male alpacas (machos) and 97 female alpacas (hembras) obtained during three spring (mid-October to early December, n = 96) and four autumn (mid-February to March, n = 98) joining periods were analysed to determine the effects of season and other factors on sexual behaviour. Joining was carried out by introducing one macho to one hembra in a 5.5 m × 7 m pen. In spring, there was a higher frequency of spitting, kicking, and threatening to spit by hembras, the duration of pre-copulatory chases was longer, mating duration was shorter, and a lower percentage of hembras were mated, compared with autumn joining periods (P < 0.01). Sexually inexperienced hembras were more likely to kick, and attempt to escape from the testing pen, but were less likely to spit or threaten the macho, compared with experienced hembras (P < 0.01). Sexual receptivity was related to the performance of spitting, threatening and kicking by hembras, as these behaviours reduced the likelihood of mating (P < 0.001). It was concluded that season and previous sexual experience affected female behaviour at joining, which in turn affected mating activity. In addition, a negative relationship between the time elapsed since parturition of experienced hembras and the likelihood of mating was found (P < 0.001).

The effects of mating on the sexual receptivity of female alpacas

To describe changes in the sexual receptivity of female alpacas (hembras) following mating, hembras were either mated on Day 0 ( n=7) or remained unmated as a control ( n=7). The sexual receptivity of hembras was tested on Days 0–9, by confining each hembra separately in a pen with a male alpaca (macho) for 30 s. Laparoscopic determination of ovarian activity on Day 6 revealed that a corpus luteum was present in four of six of the mated hembras. The two remaining hembras and four of the unmated animals had luteinised and antral follicles. The remaining three unmated hembras had antral follicles only. Mated hembras spat, kicked, vocalised and attempted to escape from the testing pen during more of the receptivity tests than control hembras ( P<0.05). Spitting and attempting to escape were also more prevalent in hembras with a corpus luteum than in those with luteinised or antral follicles ( P<0.05). Despite the widely held belief that hembras adopt a position of ventral recumbency if they are sexually receptive, no relationship between this behaviour and mating behaviour or ovarian status was found, perhaps because the testing procedure caused stress-induced sitting.

Clinical biochemical reference ranges for female alpacas ( Lama pacos)

1. 1. Serum samples were collected from 352 healthy female alpacas and tested for 17 clinical biochemical analytes. 2. 2. From the total population of alpacas tested, 205 were pregnant, 68 were not pregnant and 79 had an unknown pregnancy status. 3. 3. Reference ranges for the female alpacas were determined for all the biochemical analytes, and compared to ranges reported for llamas, cattle, sheep and goats. 4. 4. The mean values for pregnant and non-pregnant females were compared and any statistically significant differences identified. 5. 5. The biochemical values reported here are suitable as reference ranges for pregnant and non-pregnant female alpacas.

Sexual receptivity and time of ovulation in alpacas

Using laparoscopy, different degrees of sexual receptivity and time of ovulation after single copulation were determined in alpacas. Sexual receptivity was assessed with intact males in 39 adults (? 3 years old) and 37 yearlings (12–14 months) and then laparoscopy was performed to correlate it with size of ovarian follicles. Time of ovulation was also determined at two different times after copulation. Females exhibited three degrees of sexual receptivity: immediate and slow acceptance, and refusal, with no difference between yearlings and mature animals ( P>0.05). Female alpacas bred over a wide range of follicle size with no differences between ages ( P0.05). Fifty percent of females ovulated at a normal time (30 h after copulation), 24% ovulated late (72 h), and ovulation was not observed in 26% of females. Forty percent of the animals that failed to ovulate were yearlings and 15% adults ( P<0.05). The average follicle size that ovulated was 8.1 mm, with 7 mm as the minimum size for ovulation, and with no association between follicle size and time of ovulation.

Economic benefits of controlling internal and external parasites in South American camelids.

A trial was carried out in alpacas (Lama pacos) and llamas (Lama glama) to determine the economic benefits of controlling both external and internal parasites by the use of ivermectin ("Ivomec," Merck Sharp & Dohme). After four months the treated male alpacas gained on average 3.1 kg more than the untreated males, and their fleece weighed 0.36 kg more. The treated female alpacas gained 1.9 kg more than the controls, but their fleece weighed 0.03 kg less. This treatment gave a net financial benefit to the farmer of U.S. $3.54 for each of his male alpacas and U.S. $1.36 for each of his female alpacas. The results for the llamas were not significant because there was great variation in the weight gains (and losses). Because the value of llama fleece is less, the economic benefits were also less.

Dry Season Forage Selection by Alpaca [Lama pacos] in Southern Peru

Two hundred eighty adult female alpacas (Lamapacos) and 200 tui alpacas (young alpacas 3-7 months of age) were grazed on a Festuca-Calamagrostis association at the South American Camelids Research Station, La Raya, Peru, during the dry season and early wet season of 1981 (June-December). Vegetation was sampled monthly during this period for herbage yield by species. Fecal material from both adult female alpaca and tui alpaca was collected monthly for microhistological analyses of food habits. Alpacas were primarily grazers rather than forb eaters during the dry season and early wet period of 1981. Forage classes consumed were different for adult and tui alpaca. Tui alpaca consumed more grass-like plants and forbs than adults during the driest months. Diet indices revealed the following as highly selected, common forage species: Ekharis at%ibracteata, Poa. sp., Cahunagrostis heterophyk, C. vicunarum, AIchemiUa pinnata, Muhtenbergia f&igiata, and Carex spp. Highly selected, trace species were P. gymnontha, M. peruviana, Stipa brachiphylla, Ranunculus lbnosellokies, and TrVolium amabile. Festuca dohkhophylla had been considered by range managers as highly preferred species overall. However, because it was the most abundant species (73% of the total forage yield), F. dolichophyllk had a low selection index during the dry season. Alpacas consumed remarkable quantities of grass seeds (up to 20% of the diet) during the driest months of the year, apparently compensating for low quality forage. The Andes of Peru comprise about 22 million ha of rangeland and support more than 50% of the domestic livestock in Peru (San Juan de Chuquibambilla 198 1). The “Altiplano” or highland plateau accounts for 7 million ha. Large-scale cultivation in the Altiplano is not feasible and economy primarily is dependent upon herding by local pastoralists. There are 4 species of New World Camelids: the alpaca (Luma paces). the llama (L. glama), the vicuna (Vicugna vicugna), and the guanaco (I!.. guanicoe) (Reiner and Bryant 1983). The 2 former species are domesticated and the latter 2 are wild. The entire population of these mammals is distributed in the Andes of Peru, Bolivia, Chile, and Argentina. Most alpacas and llamas are in Peru and Bolivia, a few are in Chile, but practically none occur in Argentina. The alpaca is a dual purpose animal because it produces high quality fiber that is exported, and meat that is needed by a growing population. Because of current husbandry practices, rangelands are severely overgrazed (Holgado et al. 1979). Also, poor grazing practices are confounded with the seasonal distribution of precipitation. About 80% of the rainfall comes during the wet season

Effect of different mating stimuli on induction of ovulation in the alpaca.

Summary. The ovulation response following different mating stimuli was studied in 177 adult female alpacas killed 72 hr after mating. Ovulation rates in females that received a mounting stimulus alone, either by aproned males or other females, were low and did not significantly differ from those controls which did not receive any stimulus. Single services by intact, or vasectomized males caused ovulation in 77 to 82% of the females, a significant increase over the previous treatments. Increasing the number of services by intact males to three within 24 hr, or interrupting services 5 min after their initiation, did not significantly affect ovulation or fertilization rates, as compared to single or uninterrupted services. Single hcg injections to females in oestrus induced ovulation in all cases. Results indicate that mounting accompanied by penile intromission is necessary to provide an adequate stimulus for lh release and subsequent ovulation in the alpaca.