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PubMed2005

Fertility in heifers and cows after low dose insemination with sex-sorted and non-sorted sperm under field conditions.

The present study was performed to test fertility after low dose insemination with sexed and non-sexed sperm in dairy cattle under field conditions in Switzerland. Spermatozoa were stained with Hoechst 33342 and sorted by flow cytometry. A total of 132 heifers and cows were inseminated with 2 x 10(6) X-bearing, frozen-thawed sperm (A) and 91 animals were inseminated with the same dose using non-sorted, frozen-thawed sperm (B). Pregnancy examination by ultrasound was performed twice, 30-40 days (PE1) and 70-90 days (PE2) after insemination. The pregnancy rates after PE1 were 33.3% (9/27) and 59.3% (16/27) in heifers (P=0.05) and 27.6% (29/105) and 28.1% (18/64) in cows (P>0.05) for groups A and B, respectively. Embryonic losses between PE1 and PE2 in heifers were 11.1% (1/9) and 0% (0/16) and in cows 17.2% (5/29) and 5.6% (1/18), the differences between groups A and B not being significant (P>0.05). Calving rates in heifers were 29.6% (8/27) and 57.8% (15/26), whereas in cows 22.1% (23/104) and 23.4% (16/63) gave birth to calves (for both groups P>0.05). The sex ratio was different (P<0.05) between A (85.3%) and B (58.6%). From our results it can be concluded that conception rates of sorted and non-sorted semen are similar using an insemination dose of 2 x 10(6). Fertility may be increased by improving sexing technology and animal management.

Animals↗
PubMed2006

Artificial insemination of cows with semen in vitro contaminated with Neospora caninum tachyzoites failed to induce neosporosis.

Neosporosis is a major cause of abortion in cattle all over the world. Congenital transmission as well as horizontal transmission by ingestion of oocysts has been described. The detection of Neospora caninum DNA in bull semen warrants the investigation of possible transmission through the use of contaminated semen. In this experiment four cows were artificially inseminated with frozen-thawed semen contaminated in vitro with viable N. caninum tachyzoites (group A) and four control cows were inseminated with tachyzoites-free frozen-thawed semen, from the same bull (group B). Serum samples were collected 15 days before the artificial insemination (AI) and at days 10, 14, 21, 28, 45, 60 and 75 post-insemination. All sera samples were tested for neosporosis by direct agglutination test (DAT). Three of the cows from group A had negative DAT titers (< or =1:20) in all of the samples, while the fourth cow from this group had a low titer of antibodies (1:80) at day 10, and became negative at day 45, suggesting a stimulation of the immune system by the tachyzoites placed in uterus, rather than the induction of an infection. All of the cows from group B had negative DAT titers (< or =1:20) in all of the samples. These results suggest that transmission of neosporosis by artificial insemination with frozen-thawed semen is an unlikely event.

Abortion, Veterinary↗
PubMed1975

Current status of artificial insemination with donor semen.

As male infertility secondary to oligospermia and azoospermia reamins refractory to treatment, donor insemination has gained greater acceptance. Wives of azoospermic and severely oligospermic men were evaluated for donor insemination. One hundred and thirty-four patients were found to be ovulating normally and to be free from pelvic pathology.Sixty-five accepted donor insemination. Fifty-one conceptions accurred in 41 patients, resulting in 43 live births and 8 miscarriages. The mean number of inseminations was 4.2 (range 1 to 13). Eighty-three patients were found to have endocrinopathies or pelvic pathology interfering with fertility; 58 were considered candidates for corrective therapy to be followed by donor insemination. Conception rates approached those observed in the average population; however, there was a greater incidence of abortion and ectopic gestation. Careful consideration of the patient prior to donor inseminationensures greater success and avoids unnecessary procedures when the patient is not considered a candidate for corrective therapy.

Abortion, Spontaneous↗
PubMed1990

Does intraperitoneal insemination in the absence of prior sensitization carry with it a risk of subsequent immunity to sperm?

To evaluate the occurrence of antisperm antibodies in women, with no prior sensitization, 112 couples undergoing intraperitoneal insemination were tested for serum antisperm antibodies with the sperm immobilization test (SIT) and the immunobead test (IBT). A serum sample was taken from each of the 112 patients immediately before the first intraperitoneal insemination. Another sample was taken from 58 patients who underwent a second insemination procedure. In 16 of the 58 patients the IBT results were positive for one or more immunoglobulin classes. Five patients showed positive SITs. In 7 out of these 16 subjects (12%) the antibodies were bound to the head and to the shaft of the sperm tail. Five of the six patients submitted to a third intraperitoneal insemination procedure showed unchanged SIT values and IBT binding percentages. In one subject, SIT (6 months after the third insemination) became negative. Antibody production may be either a transient response to massive antigen stimulation or the first step toward systemic immunity.

Antibodies↗
PubMed1992

Evaluation of 225 patients undergoing subzonal insemination for the procurement of fertilization in vitro.

OBJECTIVE: To evaluate subzonal insemination for the procurement of fertilization in infertile males. DESIGN: The spermatozoa of infertile males was used, where possible, for in vitro fertilization (IVF) and subzonal insemination with the same cohort of oocytes obtained from their partner. SETTING: An individual unit in a general hospital, Clinical Nomentana, Rome, Italy. PATIENTS: Males who had repeatedly failed to achieve conception in vitro by IVF or in whom seminal parameters were unacceptable for IVF were treated. INTERVENTIONS: Two hundred twenty-five transvaginal oocyte retrievals were performed. MAIN OUTCOME MEASURES: The incidence of fertilization, cleavage, and pregnancy was evaluated in relation to the numbers of spermatozoa injected and the individual spermatozoa parameters. RESULTS: Fertilization occurred in 39% of patients and 16% of eggs, and 12 clinical pregnancies were established. Fertilization increased with increasing numbers of spermatozoa injected. Fertilization with subzonal insemination was significantly greater (39%) than after in vitro insemination (6%) (P less than 0.0001). CONCLUSIONS: Subzonal insemination improved the incidence of fertilization in this series of patients, and a new classification of spermatozoa based on total motile count aided prognosis for fertilization.

Adult↗
PubMed1994

Development of a predictive model for optimal zona pellucida binding using insemination volume and sperm concentration.

OBJECTIVE: To develop a predictive model under hemizona assay (HZA) conditions for human spermatozoa concentrations and insemination volume for optimum zona pellucida (ZP) binding. DESIGN: Analysis of 20 different insemination volumes for zona binding and sperm morphology under HZA conditions. SETTING: Reproductive biology unit, tertiary medical center. PATIENTS: Four proven fertile sperm donors. MAIN OUTCOME MEASURES: 5-, 20-, 50-, 80-, and 100-microL droplets were analyzed with four different concentrations of 0.5 x 10(6), 1.0 x 10(6), 2.0 x 10(6), and 4.0 x 10(6) cells/mL to determine the number of sperm bound to each hemizona. Fifteen hemizonae were used for each insemination volume or microdroplet. Response surface regression model with volume and concentration as the regressor variables has been used. RESULTS: The response surface of binding for the factors concentration and volume showed nonlinear association. A formula, indicating the optimal sperm insemination volume for maximum sperm binding to the ZP, Vmax = -(b1 + b5c)/2b6c, is described. The transformed data indicated 60 microL containing 4 x 10(6) sperm/mL to be optimal. Although morphology of zona spermatozoa is superior compared with seminal and postswim-up samples, no difference among the percentage of the normal morphology in different microdroplets could be demonstrated. CONCLUSION: Optimal volume for the obtained concentration of spermatozoa from a patient can be calculated and therapeutically used for cases of severe oligozoospermic patients by microvolume inseminations in IVF practice.

Female↗
PubMed1995

Fertilization rates using intracytoplasmic sperm injection are greater than subzonal insemination but are dependent on prior treatment of sperm.

OBJECTIVE: To determine a suitable method of sperm preparation for use in micromanipulation. To compare the fertilization rates of sibling oocytes inseminated by intracytoplasmic sperm injection (ICSI) and subzonal insemination (SUZI). DESIGN: Two methods of gamete micromanipulation to overcome male factor infertility were compared. Within this study, three trials were conducted to determine the most suitable method of sperm preparation. This method then was used to complete the study. SETTING: Procedures were performed in a teaching hospital research environment. PATIENTS: Ninety-six patients were recruited for this study, undergoing 99 stimulation cycles. INTERVENTIONS: Sibling oocytes were inseminated by subzonal sperm or intracytoplasmic injection. MAIN OUTCOME MEASURES: Fertilization, zygote development, and pregnancy rates. RESULTS: In the absence of manipulative pretreatment of sperm (trial 1), there was no difference in normal fertilization rates between ICSI and SUZI (19% and 25%, respectively). In the second trial there again was no sperm pretreatment for SUZI but, for ICSI, a polyvinylpyrrolidone (PVP) solution was used to reduce sperm velocity and the sperm tails were incised before injection. The fertilization rates were significantly different between ICSI (44%) and SUZI (17%). In the third trial, PVP was added to the sperm used for both types of insemination and the sperm tails also were incised for the ICSI insemination. Fertilization was again significantly different (16% for SUZI and 44% for ICSI). The trial 2 method of sperm preparation then was used to complete the study (trial 4) and confirmed the results of trial 2 (21% for SUZI and 42% for ICSI). The results suggest that ICSI can give improved fertilization compared with SUZI provided the sperm are treated before injection. No significant differences were found in the development rates of zygotes suitable for transfer or cryopreservation between the two micromanipulation methods.

Cytoplasm↗
PubMed1996

Donor insemination: a comparison of lesbian couples, heterosexual couples and single women.

OBJECTIVE: To compare single women, lesbian couples, and heterosexual couples receiving therapeutic donor insemination (TDI). DESIGN: Chart review followed by anonymous mail questionnaires to donor insemination recipients and their partners. SETTING: Infertility clinic in a university hospital. PATIENTS: One hundred fifteen women receiving donor insemination were identified by chart review. RESULTS: Too few single women responded for reliable comparison. Lesbian women were similar to married women in age, education, duration, and outcome of donor insemination. When considering alternatives to TDI, married women were more likely to consider adoption and lesbians were most likely to consider using a known semen donor or having intercourse with a man aware of their desire to have a child. Married couples were less likely to tell others, including the child, about conception by donor insemination. They were also less likely to support disclosing identifying data about the donor to the child. Lesbians were more likely to report stress in their relationships as a result of TDI. Married men were most likely to support mandatory counseling before TDI initiation.

Adoption↗
PubMed1989

The relationship of sperm parameters to cycle fecundity in superovulated women undergoing intrauterine insemination.

Semen parameters of raw and prepared (post-swim-up) specimens from 451 cycles of intrauterine insemination (IUI) were analyzed in relation to cycle fecundity in 232 patients undergoing ovarian stimulation with sequential clomiphene citrate/menotropin therapy. Pregnancy occurred in 42 cycles, resulting in an overall pregnancy rate of 17.7%, and a cycle fecundity of 9.3%. Cycle fecundity was positively correlated with the parameters of post-swim-up log sperm density (r = 0.994), and with log total motile sperm inseminated (r = 0.964; inseminates were limited to a maximum of 20 million total motile sperm). Post-swim-up motility did not correlate (r = 0.308) with cycle fecundity; however, most specimens had a motility of greater than 40% post-swim-up. Only one pregnancy occurred when less than 1 million motile sperm were inseminated (38 cycles), which resulted in a cycle fecundity of 2.6% for these cycles. This may represent the threshold of effectiveness for IUI in this setting. Highest cycle fecundity was obtained with an inseminate containing approximately 10 million or more motile sperm. Parameters of raw samples correlated less well with cycle fecundity than did prepared specimens. Analysis of post-swim-up semen parameters can provide useful prognostic information for women undergoing IUI with ovarian stimulation; this information is helpful in counseling patients regarding their chances of success with this therapy.

Adult↗
PubMed2000

Importance of inseminating only cows in estrus.

Reproductive efficiency is a key component in successful dairy farm management. A study was initiated to evaluate the incidence and consequences of inseminating dairy cows in the middle of the estrous cycle or while pregnant. In a research herd of 242 Holsteins, managed for reproduction under typical farm conditions, milk progesterone (P4) was assayed 3 times per wk for at least 120 d postpartum. The P4 cycle was compared with the estrus detection and breeding records and pregnancy diagnosis 6 wk after insemination. About 19% of the inseminations were performed when P4 was high in the estrous cycle and in pregnant cows. Insemination of pregnant cows led to an estimated 17% induced embryonic death or abortion. In Israel, inseminators are extensively trained to detect cows not in estrus. They reject about 16% of the cows submitted for reinsemination, with a 95% accuracy of rejection of 44% of the cows that were pregnant. The pattern of submission of cows for reinsemination in areas around New York State was similar to Israel and to the experimental herd. These results indicate that more careful submission and rejection can reduce the unnecessary use of semen, reduce abortions and minimize long calving intervals, all contributing to the success of a dairy herd operation.

Abortion, Veterinary↗
PubMed2001

Do sire-dam interactions contribute significantly to fertility comparisons in heterospermic insemination trials.

The percentage of offspring sired after heterospermic insemination of equal numbers of spermatozoa is believed to be a very sensitive measure of relative in vivo fertility of the inseminated samples. The objective of these trials was to evaluate whether there was a detectable male-female interaction in the fertilizing ability of spermatozoa. If there was such an interaction, we reasoned that the paternity of offspring from individual females in a heterospermic trial the second year would be similar to the paternity of offspring in the same individual females the first year if the same ejaculates were used. Five groups of ewes were inseminated with different combinations of semen (a single Merino ejaculate from one of five rams randomly paired with five different pools of Suffolk semen) in a heterospermic trial. Those ewes conceiving the first year were inseminated in a second breeding season with the same combination of semen used previously. The percentage of lambs sired by each ejaculate/pool of ejaculates was calculated for all lambs born from all ewes inseminated with each semen combination. These percentages would be the expected ratios of Merino-sired:Suffolk-sired lambs if there is no male-female interaction. Ewes in each group were divided into two subgroups: those conceiving only Merino-sired lambs the first year and those conceiving at least one Suffolk-sired lamb the first year. The ratio of Merino-sired lambs:Suffolk-sired lambs did not differ in either subgroup from those expected if there was no male-female interaction. These results are consistent with the absence of a male-female interaction in relative fertilizing ability of spermatozoa.

Animals↗
PubMed2003

Fertility of weaned sows after deep intrauterine insemination with a reduced number of frozen-thawed spermatozoa.

The present study evaluates the effectiveness of the transcervical deep intrauterine insemination (DUI) with a reduced number of frozen-thawed boar spermatozoa in weaned sows. DUI was performed using a specially designed flexible device (length 180 cm, outer diameter 4mm, working channel 1.8mm, working channel's volume 1.5 ml) that was inserted through an artificial insemination spirette to cross the cervix lumen and moved into one uterine horn as far as possible. Spermatozoa diluted in 7.5 ml of BTS were flushed into the uterine horn by a syringe attached to the working channel. In Experiment 1, 111 hormonally treated (eCG/hCG) weaned sows were inseminated once using one of the following three regimens: (1) DUI with frozen-thawed spermatozoa (1000 x 10(6) cells per dose; n=49); (2) DUI with fresh semen (150 x 10(6) cells per dose; n=29, as control of DUI procedure); and (3) cervical insemination with frozen-thawed spermatozoa (6000 x 10(6) cells diluted in 100ml; n=33). No differences (P>0.05) were found for farrowing rates (77.55, 82.76, and 75.76, respectively) or litter sizes (9.31+/-0.41, 9.96+/-0.32, and 9.60+/-0.53 piglets born per litter, respectively) among the groups. In Experiment 2, DUI was performed on the spontaneous estrus in weaned sows (2-6 parity) with 1000 x 10(6) frozen-thawed (40 sows) or 150 x 10(6) fresh spermatozoa (38 sows). The farrowing rate of sows inseminated twice with frozen-thawed spermatozoa (70%) was significantly (P<0.05) lower than with fresh semen (84.21%). No significant difference (P>0.05) was found in litter size between frozen-thawed spermatozoa (9.25+/-0.23 piglets born per litter) and fresh semen (9.88+/-0.21 piglets born per litter). These preliminary results indicate that application of DUI provides acceptable fertility in weaned sows using a relatively low number of frozen-thawed spermatozoa.

Animals↗
PubMed1999

Follicular growth, estrus and pregnancy after fixed-time insemination in beef cows treated with intravaginal progesterone inserts and estradiol benzoate.

An experiment was performed to compare the effects of 3 short-term treatments with progesterone and estradiol benzoate (EB) on follicular growth, synchrony of estrus and pregnancy rate after fixed-time insemination in lactating postpartum beef cows. In Treatment 1 (n = 46), each cow received a progesterone-containing intravaginal insert for 7 d with injection of EB (2 mg, i.m.) at the time of device insertion. In Treatment 2 (n = 46), the insert was used for only 5 d with injection of EB (2 mg, i.m.) at the time of insertion. Cows in Treatment 3 (n = 47) received an insert for 5 d with no EB at the time of insertion. Each cow in the 3 groups received PGF2 alpha (25 mg, i.m.) at the time of insert removal, followed by EB (1 mg, i.m.) 30 h later. The cows were then inseminated 28 to 30 h after treatment with EB (58 to 60 h after insert removal). Treatment with 2 mg EB terminated the growth of the largest ovarian follicle (> 5 mm in diameter) at device insertion in 16/16 and 14/15 cows in Treatments 1 and 2, respectively. Estrus was detected within an 8-h target period (48 to 56 h after insert removal) in 93, 87 and 81% of cows in Treatments 1, 2 and 3, respectively (P > 0.05). Pregnancy rates at 39 d post insemination were 60, 50 and 51% for Treatments 1, 2 and 3, respectively (P > 0.05). The pregnancy rates did not differ between cows that were anovulatory or those that had ovulated before the initiation of treatments (54%), or among cows that were 28 to 40, 41 to 60 or > 60 days post partum at insemination (43, 59 and 54%, respectively). Treatment with progesterone inserts for 5 or 7 d, PGF2 alpha at the time of insert removal and 1 mg EB 30 h later induced the high degree of synchrony of estrus and ovulation necessary for fixed-time insemination.

Administration, Intravaginal↗
PubMed2006

Intrauterine insemination with controlled ovarian hyperstimulation versus expectant management for couples with unexplained subfertility and an intermediate prognosis: a randomised clinical trial.

BACKGROUND: Intrauterine insemination with controlled ovarian hyperstimulation is commonly used as first-line treatment for couples with unexplained subfertility. Since such treatment increases the risk of multiple pregnancy, a couple's chances of achieving an ongoing pregnancy without it should be considered to identify those most likely to benefit from treatment. We aimed to assess the incremental effectiveness of intrauterine insemination with controlled ovarian hyperstimulation compared with expectant management in couples with unexplained subfertility and an intermediate prognosis of a spontaneous ongoing pregnancy. METHODS: 253 couples with unexplained subfertility and a 30-40% probability of a spontaneous ongoing pregnancy within 12 months were randomly assigned either intrauterine insemination with controlled ovarian hyperstimulation for 6 months or expectant management for 6 months. The primary endpoint of this hospital-based study was ongoing pregnancy within 6 months. Analysis was by intention to treat. This trial is registered with the Dutch Trial Register and as an International Standard Randomised Clinical Trial, number ISRCTN72675518. FINDINGS: Of the 253 couples enrolled, 127 were assigned intrauterine insemination with controlled ovarian hyperstimulation and 126 expectant management. In the intervention group, 42 (33%) women conceived and 29 (23%) pregnancies were ongoing. In the expectant management group, 40 (32%) women conceived and 34 (27%) pregnancies were ongoing (relative risk 0.85, 95% CI 0.63-1.1). There was one twin pregnancy in each study group, and one woman in the intervention group conceived triplets. INTERPRETATION: A large beneficial effect of intrauterine insemination with controlled ovarian hyperstimulation in couples with unexplained subfertility and an intermediate prognosis can be excluded. Expectant management for 6 months is therefore justified in these couples.

Adult↗
PubMed1998

Timed intercourse after intrauterine insemination for treatment of infertility.

OBJECTIVE: To compare the pregnancy rates, between intrauterine insemination (IUI) followed by timed intercourse and IUI only for treatment of the infertile couples. STUDY DESIGN: A prospective study of two different protocols of intrauterine insemination in two hundred and one infertile couples with a normal spermiogram was carried out. Of these, 101 couples were treated with IUI alone and 100 couples had both IUI and timed intercourse within a 12-18 h period. The pregnancy rates were compared between groups. RESULTS: The characteristics of the two groups were similar in terms of the mean age, as well as the duration and causes of infertility. The cycle characteristics following follicular stimulation were also similar between two groups. The pregnancy rate per cycle increased with increasing numbers of total motile sperm per insemination in the IUI alone group (P=0.045). Timed intercourse increased pregnancy rate in patients with lower motile sperm number (<40x10(6)) (27.7% versus 10.5%, P=0.023), but not in patients with higher sperm number (> or =40x10(6)) (25.7% versus 22.7%, P=0.671). CONCLUSIONS: In IUI with low number of motile sperm inseminated, timed intercourse significantly increases the pregnancy rates over IUI alone in infertile couples with a normal sperminogram. This alternative treatment appears to be a practical, simple, and inexpensive addition that improves the pregnancy rate in patients receiving ovulation induction and intrauterine insemination program.

Adult↗
PubMed2000

Relationship of seminal traits and insemination time to fertilization rate and embryo quality.

The nature of subfertility due to the male or inseminate is as complex as that of the female. Fertilization failure or failure in embryogenesis are both documented to be of seminal origin. Males also differ in the numbers of sperm required to reach their maximum fertilization rate. Males requiring more sperm would be considered to have compensable seminal deficiencies. These include a number of known (viability and morphology) and unknown factors (functional or molecular traits) precluding sperm access to the ovum or ability to engage the ovum sufficiently to initiate fertilization and the block to polyspermy. Differences in fertility among males or inseminates independent of sperm dosage are considered uncompensable. These deficiencies would be associated with fertilizing sperm that are incompetent to maintain the fertilization process or subsequent embryogenesis once initiated, with most failures occurring prior to maternal recognition of pregnancy. Such sperm would preempt fertilization by competent sperm. Chromatin aberrations in morphologically normal or near normal spermatozoa from abnormal semen samples appear to be the best candidates for the uncompensable deficiency. However, recognition of uncompensable or incompetent fertilizing sperm has not been achieved. Six-day-old non-surgically recovered bovine ova/embryos have been used to evaluate compensable and uncompensable seminal deficiencies as well as to test reproductive strategies. These ova/embryos provide information on fertilization status and embryo quality as well as quantitative and qualitative data regarding associated accessory sperm. Thus, they permit the separation of reproductive failure by fertilization from that by embryonic development. Accessory sperm number is positively associated with both fertilization rate and embryonic quality. Early insemination results in low fertilization rates (low accessory sperm number), but good embryo quality, whereas, late insemination results in high fertilization rates (high accessory sperm number), but poor embryo quality. Additional studies will be necessary to substantiate this model; however, if true, future research designed to improve results to artificial insemination should be tested by breeding early in estrus where sperm viability is most limiting and embryo quality is best.

Animals↗
PubMed2002

The relationship between rabbit semen characteristics and reproductive performance after artificial insemination.

The relationships between several rabbit buck semen traits, concerning either the ejaculate or the dose inseminated (volume, mass motility, pH, percentage of motile sperm (PMS), concentration, number of total and motile sperm per ejaculate and per insemination dose) and the reproductive performance of does was investigated in 839 inseminations involving 54 bucks and 111 does. Four genetic types were involved: INRA1601 strain (A), INRA2066 strain (B) and the two reciprocal crossbreds (AB and BA). The mating design was A x A, B x B, (AB or BA) x (AB or BA). Semen was diluted (1:9) and a constant volume of 0.5 ml was inseminated 2-4h after collection. Therefore, the total number of spermatozoa per dose was variable and proportional to the initial concentration. Mass motility significantly influenced the kindling rate. Taken separately, volume, PMS and concentration did not influence the kindling rate but their product, the number of motile sperm per ejaculate, did. Litter size (total born) was significantly influenced by concentration and all variables depending on it, particularly the number of total and motile sperm per dose. However, reproductive performances were predominantly influenced by the physiological status of the does at insemination (lactation stage and receptivity).

Animals↗
PubMed2003

Influence of short-term relocation and male exposure on sexual receptivity and reproduction in artificially inseminated lactating doe rabbits.

A study was conducted to evaluate the effect of short-term relocation and male exposure on receptivity rate, kindling rate and total born per litter in lactating does under an artificial insemination (AI) programme. Thirty-two, 2-month-old New Zealand White rabbits were randomly allocated to one of four treatments: (1) relocation and male exposure; (2) relocation without male exposure; (3) no relocation with male exposure; (4) no relocation without male exposure (control). Relocation and male exposure were done 8-10 h before the time of service. First insemination was when does reached 3200 g body weight and does were bred 4-13 days after parturition across parities during a 6 month reproduction period. Of all breeding records, 125 inseminations and 91 kindlings were from nursing does. The mean interval from parturition to insemination for nursing does was 10.3 days. Relocation of lactating does resulted in greater (P<0.01) receptivity rate at service (74.8%) as compared with no relocation (55%). Receptivity rate was not influenced by male exposure. However, the interaction of relocationxmale exposure tended to be significant (P=0.07). Receptivity rate in relocated does exposed to males was 62.8 and 86.7% without exposure while in non-relocated does male exposure showed no effect. Kindling rate was not influenced by relocation or male exposure. The mean total born per litter in relocated and non-relocated does was 8.05 +/- 0.33 and 7.39 +/- 0.36, respectively, but no significant difference was observed. There was no effect of male exposure on total born per litter (7.85 +/- 0.34 versus 7.59 +/- 0.34 without male exposure). However, interaction of relocationxmale exposure on this variable was significant (P=0.009). Male exposure in relocated does decreased the size of the litter (7.52 +/- 0.46 versus 8.58 +/- 0.47 without male exposure) whereas mean values in non-relocated does increased when they were exposed to males (8.18 +/- 0.52 versus 6.60 +/- 0.49). Short-term relocation improved receptivity rate and reproduction in lactating does under an artificial insemination programme. Preliminary results indicated that male exposure in non-relocated does improves the total born per litter at a similar level than relocated does without male exposure. Relocation combined with male exposure decreased receptivity rate and total born per litter as compared with relocated does without male exposure, but the reproductive performance in the former was greater as compared with those does where no relocation occurred without male exposure.

Animals↗