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PubMed1999

Effect of insemination of estrus-induced prepuberal gilts on ensuing reproductive performance and body weight.

Prepuberal gilts reared and managed to 85-90 kg live weight in a common system were allocated at random to one of three first-mating treatments in an experiment conducted over a period of more than 5 years. In two of the treatments, gilts received a single i.m. injection of 400 IU equine chorionic gonadotropin (eCG) and 200 IU human chorionic gonadotropin (hCG) (PG600; Intervet) and were either inseminated 4 and 5 days later on a fixed-time basis regardless of oestrus (treatment A), or at the second oestrus following treatment (treatment B). The third group of gilts remained untreated and was inseminated on the first spontaneous oestrus (treatment C). Thereafter, all gilts were managed in the same way and those observed in oestrus were re-inseminated. Significantly more gilts returned to oestrus after the first service in treatment A (35%) than in treatment B and C (12 and 17%, respectively; P<0.01). Gilts farrowed to the first or repeat inseminations at a significantly younger age (P<0.01) in treatment A (304 days) than treatment B (324 days) and C (320 days). The age difference at farrowing remained in surviving gilts at the end of their third parity. The first farrowing performance of the gilts was significantly affected by treatment in terms of litter size at birth (A 7.0, B 8.4 and C 8.3 live piglets per gilt; P<0.01), litter size at weaning (A 6.2, B 7.2 and C 7.2 live piglets per gilt, P<0.05), and piglet birth weight (A 1.4, B 1.3 and C 1.3 kg; P<0.05) but piglet survival rate and weaning weight were not affected by treatment. The live weights of the gilts were significantly different between the treatments at first insemination (A 95.7, B 106.5 and C 109.2 kg; P<0.01) but not when the first litter was weaned (A 133.6, B 135.1 and C 136.6; P>0.05). After the first farrowing there were no differences between the treatments in terms of the survival rate, productive or reproductive performance of the gilts/sows and their offspring. Without conducting a detailed cost-benefit-calculation it was deduced that, from an economical point of view, differences between treatment A and treatments B and C are negligible because the savings associated with farrowing at a younger age on this treatment just about compensated for any additional costs associated with the treatment and the lower number of piglets born at the first farrowing.

Animals↗
PubMed2003

Influence of post-ovulatory insemination on sperm distribution, pregnancy and the infiltration by cells of the immune system, and the distribution of CD2, CD4, CD8 and MHC class II expressing cells in the sow endometrium.

This study investigates the distribution of leucocytes, CD2+, CD4+, CD8+ lymphocyte subpopulations and MHC class II expressing cells in the sow endometrium following post-ovulatory insemination in relation to clinical findings and pregnancy outcome. Crossbred multiparous sows were inseminated once either at 15-20 h after ovulation [experiment 1, slaughtered at 20-25 h (5-6 h after artificial insemination (AI), group 1-A, n = 4), at 70 h after ovulation (group 1-B, n = 4), on day 11 (group 1-C, n = 4, first day of standing oestrus = day 1) or on day 19 (group 1-D, n = 4)] or 30 h after ovulation [experiment 2, slaughtered at 5-6 h after AI (group 2-A, n = 4) or on day 19 (group 2-D, n = 3)]. The uterine horns were flushed to control for the presence of spermatozoa and neutrophils and/or for recovery of oocytes and/or embryos. Mesometrial uterine samples were plastic embedded and stained. Cryofixed uterine samples were analysed by immunohistochemistry using mAbs to lymphocyte subpopulations and MHC class II molecules. Light microscopy was used to examine surface (SE) and glandular epithelia (GE), and connective tissue layers, both subepithelially (SL) and glandular (GL). In experiment 1, group 1-A, only one sow had spermatozoa in the utero-tubal junction (UTJ). Marked/moderated numbers of neutrophils and spermatozoa were observed in the flushings of two sows. In group 1-B, altogether 23 of 48 oocytes were cleaved. Day 11 (1-C), embryos with small diameter were observed. Day 19 (1-D), no embryos were found but small pieces of foetal membrane were observed in one of the sows. In group 1-A, large numbers of neutrophils were found within the SE and SL but with high individual variation. For T lymphocyte subpopulations, in the SE, most CD2+ cells were found in group 1-A. For both SE and GE in all groups, the number of CD8+ cells was significantly larger than that of CD4+ cells. In experiment 2, group 2-A, no sow had spermatozoa in the UTJ or in the uterine flushings. At day 19, no sow was pregnant. In group 2-A, large numbers of neutrophils were found within the SE and SL but with high individual variation. At day 19, high E2 levels showed a hormonal prooestrous stage but the endometrial neutrophil infiltration normally expected at pro-oestrus was absent. In conclusion, post-ovulatory insemination (about 18 h after ovulation) resulted in impaired spermatozoa transport within the uterus and embryonic degeneration. In sows post-ovulatory inseminated at a later stage (30 h after ovulation), no sow was pregnant. In both experiments, disturbed immune cell patterns were observed in some individuals.

Animals↗
PubMed2001

Reproductive parameters and efficiency of inseminators in dairy farms in Portugal.

This study was carried out to determine the reproductive efficiency indices of one of the largest dairy co-operatives of northern Portugal, using data from 1980 to 1998. Records were made available by the computerized National Recording System. Age at first calving was 32.0 +/- 6.0 months. Mean calving to first AI interval was 95.4 +/- 30.0 days, and calving to conception intervals decreased (p < 0.05) from 176.9 +/- 4.5 to 148.1 +/- 5.6 days from the first to the fourth/fifth parturitions, respectively. Calving intervals decreased (p < 0.05) from 418.1 +/- 3.4 to 392.5 +/- 7.0 days from the first to fourth/fifth parturitions, respectively. Mean non-return rates at 90 days for first inseminations was 71.7 +/- 6.5% and mean calving rates at first insemination was 51.4 +/- 8.1%. There were significant differences (p < 0.001) in the inseminators' efficiency, measured by both non-return and calving rates at first AI, with differences between the best and worst results of 13.3 and 16.1% for non-return and calving rates, respectively. The ranking of the inseminators did not coincide when their efficiency was measured by either non-return or calving rates. The mean number of inseminations per pregnancy (pregnant cows only) was 1.4 +/- 0.7 with significant (p < 0.001) differences among herds. The mean heat detection rate was 38.1 +/- 16.9%, with highly significant (p < 0.001) differences among farms (ranging from 14.2 to 60.8%). Negative (p < 0.001) correlations were found between heat detection rate and calving to first AI, calving to conception and calving intervals. The meaning of these indexes for assessment of reproductive efficiency in the studied system, is discussed.

Age Factors↗
PubMed2002

Insemination of susceptible heifers with semen from a non-viraemic bull with persistent bovine virus diarrhoea virus infection localized in the testes.

Bulls shedding bovine viral diarrhoea virus (BVDV) in semen and simultaneously having a high concentration of circulating antibodies may cause reproductive problems and spread the viral infection within cattle populations. To investigate this in detail, three heifers were inseminated with BVDV-infected semen from a non-viraemic, seropositive Holstein-Friesian bull, named 'Cumulus'. One control heifer was inseminated with semen from a healthy bull that was free of BVDV. All four heifers remained clinically healthy throughout the experiment. The conception succeeded in the control animal and in two of the three heifers inseminated with semen containing BVDV. The heifer with the failed conception was the only one that became systemically infected with BVDV. This animal was deemed non-pregnant by ultrasonic examination on day 34 after insemination and showed no signs of subsequent oestrus during the entire experimental period. At slaughter, 42 days after insemination, there were no histopathological changes in the ovaries and virus was not detected in ovarian tissue. The fact that seronegative dams served with semen from persistently infected bulls have occasionally produced persistently infected calves together with the present findings and the fact that non-viraemic, seropositive bulls can constantly shed BVDV, suggest that the use of semen from such bulls in BVDV-free herds could have far-reaching consequences, especially if it led to the birth of persistently infected (P1) calves.

Animals↗
PubMed1984

Effect of semen storage time and number of spermatozoa inseminated on the fertility and hatchability of eggs from dwarf broiler breeder hens.

Semen from commercial breeder males was diluted two-fold and stored for 6 and 24 h at 2 to 3 degrees C. For each storage period, groups of caged dwarf broiler breeder hens from the same strain were inseminated with 300, 200 or 100 x 10(6) spermatozoa. Three replicates of 15 birds were inseminated per treatment. Control hens were inseminated with 150 x 10(6) fresh, undiluted spermatozoa. Inseminations were performed for 5 consecutive weeks during a first (32 to 36 weeks of age) and for 6 consecutive weeks during a second experimental period (42 to 47 weeks). During weeks 33 to 36 of the first period, only 24 h storage and 100 x 10(6) spermatozoa produced lower (P less than 0.05) hatchability of all eggs set than the control (84.4 compared to 88.6%). During weeks 43 to 47 of the second period, no significant differences between treatments were observed. Embryonic mortality, measured at different periods during incubation, was not affected by the storage time or the number of spermatozoa inseminated.

Animals↗
PubMed1996

Intramagnal insemination of hens can eliminate negative influence of lipofectin on fertilising ability of spermatozoa.

1. After intramagnal insemination egg production decreased drastically during the first two days and was equivalent to egg production of hens inseminated intravaginally for the remaining period of collection. 2. After magnal insemination, the fertility of eggs collected during the first week was 36.2% and only 3.6% during the second week. 3. In the case of intramagnal insemination, egg fertility in the first week was 88.1%, in the second week 81.8% and the third week 52.3%. 4. The eggs laid during the first day after intramagnal insemination were 83.3% fertile, indicating that treated spermatozoa fertilised the newly ovulated egg within 20 minutes of ovulation.

Animals↗
PubMed1989

Time of insemination and its effect on in-vitro fertilization, cleavage and pregnancy rates in GnRH agonist/HMG-stimulated cycles.

In this prospective study, we compared the effect of delayed inseminations on fertilization, cleavage and pregnancy rates in two groups of patients. In one group, the ovarian stimulation was performed with a clomiphene citrate/human menopausal gonadotrophin/human chorionic gonadotrophin (CC/HMG/HCG) protocol. The other group was pre-treated with gonadotrophin-releasing hormone agonist (GnRHa) and ovarian stimulation was carried out with an HMG/HCG protocol. Under both protocols, a delay of 2, 4 or 6 h in insemination showed no significant differences in the fertilization, cleavage or pregnancy rates. To find out which type of oocyte has the potential for better fertilization, cleavage and implantation, a simple oocyte classification scheme is proposed. In the GnRHa/HMG group, 9% post-mature, 90% mature and only 1% immature oocytes were retrieved. The post-mature oocytes showed a tendency towards reduced fertilization when insemination was delayed. The mature and slightly immature oocytes fertilized equally well when spermatozoa were added 2, 4 or 6 h after retrieval. Similarly, no significant difference was observed in the cleavage (80%) or fragmentation (20%) rates of these oocytes. The pregnancy rates after inseminations delayed for 2, 4 and 6 h were 14, 27 and 26%, respectively. Though these figures were not statistically significant, the 4- and 6-h groups in both the IVF and zygote intra-Fallopian transfer treatments showed a slightly improved pregnancy rate compared to the 2-h group. An insemination delay of 4 h is advocated on a routine basis.

Adult↗
PubMed1992

Slow release intrauterine insemination versus the bolus technique in the treatment of women with cervical mucus hostility.

Thirty-eight infertile women with cervical mucus hostility were divided at random into two groups for intrauterine insemination with prepared husband's semen. Eighteen women started with slow release (treatment A) and 20 with bolus (treatment B) intrauterine insemination in a cross-over study for four alternating cycles. Insemination was timed 30-36 h after a positive luteinizing hormone (LH) surge or injection of 5000 IU of human chorionic gonadotrophin, given at a follicular diameter of 18 mm during ultrasonically monitored, unstimulated cycles. A Grasby auto-syringe driver (type MS16) was used for the slow release intrauterine insemination to deliver 50 x 10(3) motile spermatozoa every minute for 3 h. Bolus intrauterine insemination was performed by deposition of 0.6 ml of prepared semen without changing the count from the swim-up portion of the washed spermatozoa. A total of 13 patients conceived, nine from 60 cycles of treatment A and four from 66 cycles of treatment B (chi-squared = 2.7143, P less than 0.05 using one-tailed statistics).

Cervix Mucus↗
PubMed1992

Fallopian tube sperm perfusion used in a donor insemination programme.

Ninety-six couples were enrolled in a programme of Fallopian tube sperm perfusion (FSP). FSP is a method combining ovarian stimulation, ovulation induction and intra-uterine insemination with a 4 ml volume of sperm suspension. Frozen/thawed donor semen was used in all cycles. A total of 196 treatment cycles were started and of these 172 were completed. Twenty cycles were cancelled because of maturation of too many follicles, a low ovarian response, or formation of ovarian cysts. Five of the women enrolled in the programme did not have any inseminations. Forty-eight pregnancies occurred (27.9% per cycle) among 45 women (49.5%). There were five spontaneous abortions and one ectopic pregnancy. Sixteen pregnancies are on-going (greater than 12 weeks) and 26 women have delivered (including two sets of triplets and one set of twins). The pregnancy rate declined from the first attempt (34.1%) to the fourth attempt (14.3%). The pregnancy rate was significantly higher in women with three to five mature follicles compared to women with two or fewer mature follicles (P less than 0.05). Cycles in which human chorionic gonadotrophin (HCG) was administered on day 11 or later had a higher pregnancy rate than cycles where HCG was administered on day 10 (P less than 0.01). There was no difference in pregnancy rates between insemination with 8-10 x 10(6) motile spermatozoa and insemination with greater than 30 x 10(6) motile spermatozoa. FSP used in a programme of artificial insemination by donor using frozen/thawed donor semen is relatively simple to perform and gives a high pregnancy rate per cycle.

Adult↗
PubMed1992

Effect of the number of inseminated spermatozoa on subsequent human and mouse embryonic development in vitro.

It has been shown, in both human and mouse in-vitro fertilization (IVF), that an excess number of spermatozoa in the insemination medium leads to reduced fertilization rates. In this study, we evaluated human embryonic development after dividing the oocytes of each of 62 IVF attempts into two groups on the basis of insemination with two widely used concentrations (50,000 and 100,000 spermatozoa/ml). The embryonic growth was retarded in the group inseminated with 100,000 spermatozoa/ml: significantly fewer fast developing embryos (4-cell and 5- to 8-cell stages) were found (53.4% in the 100,000/ml group and 65.5% in the 50,000 group; P less than 0.05). In two experimental series, mouse embryonic development was evaluated in the presence of 0, 50,000, 100,000 and 500,000 spermatozoa per ml. In the first series, the spermatozoa were present during 5-20 h after insemination, while in the second series, the spermatozoa were present during the whole culture period of 120 h. The development of mouse embryos was impaired when 500,000/ml spermatozoa were present during the whole culture period. In contrast with human IVF results, the presence of up to 500,000 spermatozoa during the first 20 h after insemination did not have any significant detrimental effect on blastocyst formation in the mouse.

Animals↗
PubMed1993

Homologous intra-uterine insemination has no advantage over timed natural intercourse when used in combination with ovulation induction for the treatment of unexplained infertility.

The objective was to evaluate the role of homologous intrauterine insemination compared with timed natural intercourse, both combined with ovulation induction, in the management of unexplained infertility. A total of 48 couples presenting at a large teaching hospital infertility clinic with unexplained infertility of at least 3 years duration comprised the main study group, and 36 couples with identical entry criteria but under the care of another clinician made up a parallel control group. A randomized design of treatment cycles with within-group and between-group controls was used. Couples in the main study group were treated with either homologous intra-uterine insemination or timed natural intercourse in gonadotrophin-releasing hormone analogue down-regulated cycles, in which ovulation was induced with human menopausal gonadotrophin and human chorionic gonadotrophin. Alternate cycles were monitored to enable optimum timing of natural intercourse provided within-group controls. Couples in the control group underwent timed homologous intravaginal artificial insemination. Cycle fecundity and pregnancy outcome in treated and control groups were monitored. Cycle fecundity of 0.11 in 85 ovulation-induced cycles was significantly higher than 0.02 in 62 within-group and 0.01 in 103 between-group control cycles. There was no difference in conception rates between homologous intra-uterine insemination and timed natural intercourse cycles with ovulation induction. Of the 11 established pregnancies in the ovulation induced group, nine delivered healthy babies (five singleton, three twin, one triplet) and two were ectopic. Results confirmed the value of active management for couples with long-standing unexplained infertility but failed to demonstrate any advantage of homologous intra-uterine insemination over ovulation induction alone.

Adult↗
PubMed1993

Fallopian tube sperm perfusion (FSP) versus intra-uterine insemination (IUI) in the treatment of unexplained infertility: a prospective randomized study.

Prospective randomization of 60 couples with unexplained infertility was performed for treatment either with intrauterine insemination (IUI), using a volume of 0.5 ml of the inseminate, or Fallopian tube sperm perfusion (FSP), using a volume of 4 ml of inseminate. The protocols for ovarian stimulation and induction of ovulation were the same in the two groups. The two groups were similar concerning age of the female at the start of treatment and the number of follicles > 15 mm diameter, the serum oestradiol concentrations and the endometrial thickness on the day of human chorionic gonadotrophin (HCG) administration. The mean (+/- SD) number of motile spermatozoa inseminated was significantly higher in the FSP group than in the IUI group (52 +/- 5 x 10(6) and 28 +/- 3 x 10(6) respectively). In the FSP group, 30 women were given a total of 52 treatment cycles; 14 clinical pregnancies occurred in this group, giving a pregnancy rate of 26.9% per cycle and 46.7% per woman. In the IUI group, 28 women were given a total of 51 treatment cycles; five clinical pregnancies occurred, giving a pregnancy rate of 9.8% per cycle and 17.9% per woman. The pregnancy rates per cycle and per woman in the FSP group were significantly higher than in the IUI group (P < 0.05, chi-square test). This study indicates that in the treatment of couples with unexplained infertility, Fallopian tube sperm perfusion (FSP) is more successful than intra-uterine insemination (IUI).

Adult↗
PubMed1994

Psychological screening and the success of donor insemination.

In a previous case series, a psychologist's rating of couples' emotional adjustment and readiness for donor insemination was predictive of pregnancy rates. We attempted to replicate this finding with an extended series of 120 consecutive couples in which each spouse filled out questionnaires when evaluated for donor insemination. The Stress and Infertility Questionnaire measured specific attitudes and anxieties about donor insemination. The Brief Symptom Inventory assessed psychological distress. The Dyadic Adjustment Scale measured marital happiness. A psychologist used these questionnaires to rate the couple's overall adjustment in regard to donor insemination. Those couples rated as distressed had a session of psychological counselling. Outcome was reviewed at a mean of 20 months after evaluation, with categories of pregnancy, continuing donor insemination, failure to begin the programme, or dropped out. For the 120 couples overall, psychological factors did not predict pregnancy outcome. Younger age of the wife did predict higher pregnancy rates.

Adaptation, Psychological↗
PubMed1994

Spontaneous ovulatory cycle donor insemination programme: prognostic indicators of a successful pregnancy.

The effects of female and male infertility factors as well as the insemination regime on the outcome of donor insemination (DI) during 1001 spontaneous ovulatory cycles were assessed. Overall, the average monthly fecundability was 4.4% and the cumulative conception rate after nine cycles was 45%. Female DI recipients' age, nulligravidity or the presence of other infertility factors were associated with a significantly lower pregnancy rate. DI recipients of azoospermic partners had a significantly higher pregnancy rate. The likelihood of a successful pregnancy was higher when more frequent (> or = 1) inseminations were used or in association with higher cervical score and larger follicle diameter at the time of insemination. We suggest that female recipients of DI should be fully investigated before commencing DI treatment. Early resort to other methods of assisted reproduction should be considered in DI recipients aged > or = 35 years, or in younger women if they fail to conceive after nine cycles of DI. More frequent and better timing of inseminations is expected to improve the fecundability rate during spontaneous ovulatory DI cycles.

Adult↗
PubMed1994

Evaluation of transvaginal sonography combined with a urinary luteinizing hormone monitor in timing donor insemination.

There remains controversy as to the most accurate method of predicting ovulation for the timing of donor insemination. In a prospective study based at a tertiary referral donor insemination clinic we have assessed the ability of a urinary luteinizing hormone (LH) kit combined with vaginal ultrasonography to predict ovulation for donor insemination. A total of 25 natural cycles were monitored from the first day of the LH surge (detected by the urinary kit). Daily transvaginal sonographic measurement of follicular size and endometrial thickness were used to predict ovulation; monitoring continued until post-ovulatory changes were seen. Transvaginal sonography combined with a urinary LH kit successfully predicted all those women who ovulated (20/25) and detected unfavourable conditions for insemination in the remaining 20% (5/25). In conclusion, where available transvaginal sonography combined with a urinary LH kit should be the method of choice for timing donor insemination.

Endometrium↗
PubMed1994

The effect of halving the standard dose of cryopreserved semen for donor insemination: a controlled study of conception rates.

Employing a common standard technique of intra-cervical insemination from straws of cryopreserved donor semen, a volume of 0.25 ml of 0.5 ml was inseminated in alternate cycles to determine if the lower volume could be used without a decrease in the conception rate. A total of 177 women were recruited and received a median of four cycles of treatment. Of these, 90 women became pregnant, 47 with 0.5 ml and 43 with 0.25 ml inseminations. The conception rates were identical for both volumes in the first nine cycles of treatment and the cumulative rates were 57.7 and 59.3%, respectively. Subsequently more pregnancies were achieved with 0.5 ml than 0.25 ml semen (nine pregnancies in 73 further cycles versus three pregnancies in 68 cycles, respectively), although the difference was not statistically significant. There were no significant differences in the women's ages, luteinizing hormone, follicle stimulating hormone, progesterone, mucus quality, mucus pH, parity or partner's diagnosis between those women who became pregnant and those who failed to conceive with either insemination dose. We conclude that the volume of semen inseminated into the cervical canal without a cervical cap can be decreased to 0.25 ml without an adverse effect on the conception rate at least in the first 9 months of treatment. This will allow more effective use to be made of valuable screened and quarantined cryopreserved semen.

Adult↗
PubMed2000

Efficacy of sperm mobility assessment in commercial flocks and the relationships of sperm mobility and insemination dose with fertility in turkeys.

Our objectives were to evaluate: 1) the efficacy of the Sperm Mobility Test on commercial turkey farms, and 2) the influence of sperm mobility phenotype on fertility when insemination parameters are varied. In research flocks, differences in sperm mobility among toms are predictive of fertility. We wanted to test the efficacy of this sire selection test in practical, real-world situations, evaluating its usefulness in terms of assessing large numbers of toms, different strains of turkeys, and variable management practices. Utilizing field study results, controlled studies were then conducted to improve test parameters. For the field trials, semen from each of 405 breeder toms (11 strains or lines) was evaluated either in duplicate (n = 285) or in triplicate (n = 120). Sperm mobility was normally distributed among all toms tested, except for one strain. Because the sperm mobility indices for toms evaluated in these field trials were higher than those observed in research flocks, the Sperm Mobility Test was modified to increase the separation between high and low sperm mobility phenotypes by increasing the concentration of Accudenz. To determine the effects of sperm mobility and insemination dose on sustained fertility through time, hens from a research flock were inseminated twice before the onset of lay with sperm from toms classified as high-, average-, or low-mobility in concentrations of 25 to 400 million sperm per artificial insemination dose, and egg fertility was evaluated over a 5-wk period. Toms with the high-mobility sperm phenotype maintained higher fertility (P < 0.05) over the 5-wk period at all insemination doses compared with toms with low-mobility sperm. Toms with high-mobility sperm sired equal numbers of poults in a sperm competition study in which numbers favored low-mobility toms by 3:1. These results demonstrate that the Sperm Mobility Test can be used for on-farm evaluation of semen quality of toms in commercial flocks and that sperm mobility influences fertility and sire fitness.

Animals↗
PubMed2003

Semen dilution prior to analysis influences the ability of the sperm quality analyzer to predict fertility whether inseminating with a constant number of sperm or a constant volume of semen.

Previous research has shown that the sperm quality index (SQI) is positively correlated with semen characteristics as well as fertility when broiler breeder semen is diluted 10-fold prior to analysis. However, research has not been conducted to establish if semen dilution rate affects the ability of the SQI to predict fertility when inseminating a constant number of sperm or a constant volume of semen. As a result, 3 experiments were undertaken. The objective of the first study was to determine if diluent, minimum essential media, or 0.85% saline affects the SQI. The second objective was to identify potential semen dilution rates for the SQI by obtaining the range in live sperm concentrations to which the SQI is most sensitive. The purpose of experiment 3 was to determine which semen dilution rate, 10-, 25-, 50-, 75-fold, or a constant concentration of 180 x 10(6) sperm/mL, yields an SQI that is most predictive of fertility. Once a week for 3 wk, 20 hens were individually inseminated with either 20 microL of 4-fold diluted semen or a constant 45 x 10(6) sperm from each of 29 broiler breeder males. To determine which semen dilution rate yielded an SQI that was most predictive of fertility, Pearson's correlation coefficients were obtained between the SQI at each dilution rate and fertility. There was no difference in the SQI due to diluent. Sperm quality index values declined logarithmically as live sperm concentration decreased. The SQI was most sensitive to live sperm concentrations from 11 to 232 x 10(6) sperm/mL. The SQI for semen diluted 10-fold was the best predictor of fertility when inseminating with a constant volume of 4-fold diluted semen (r = 0.71). When hens were inseminated with a constant 45 x 10(6) sperm/hen, the SQI for semen diluted 10- and 25-fold as well as to a constant concentration of 180 x 10(6) sperm/ mL was equally effective at predicting fertility (r = 0.59, 0.52, and 0.61, respectively). Apparently, the SQI is predictive of fertility when semen samples are diluted 10-fold prior to analysis regardless of insemination method used. Dilution beyond 10-fold appears to alter semen quality, rendering the SQI less accurate.

Animals↗