Bacteriospermia among smallholder artificial insemination boars in the Philippines and potential associated factors

Objective:To determine the prevalence of bacteriospermia,the bacterial load,and the potential factors associated with bacterial contamination in boar semen collected by local smallholder artificial insemination operators.Methods:Fifteen individual raw semen samples were collected from locally available artificial insemination boars owned by different smallholder boar operators within the 5th district of Leyte,Philippines and were subjected to standard bacteriological culture and identification,including a survey of potentially associated factors.Prevalence and bacterial count were determined accordingly,while boar characteristics and collection practices were clustered following agglomerative hierarchical clustering technique.Results:One hundred percent contamination with a bacterial count of(2.01±0.38)×10^(3) CFU/mL was observed.At least 73.33%of the samples were positive for Bacillus spp.,while other identified isolates included Enterobacter spp.,Staphylococcus spp.,E.coli,Pseudomonas spp.,Citrobacter spp.,and Klebsiella spp.Conclusions:Despite the high prevalence of bacteriospermia,the bacterial count is low.Nevertheless,on-farm practices on boar health and management,semen collection,and sanitation as well as the enhancement of basic protocols to control contamination should be conscientiously considered in smallholder artificial insemination operation.

Can the Prediction of Intrauterine Insemination Results by Used Aniline Blue Stain (ABS) and Sperm Chromatin Dispersion (SCD) Levels?

Introduction: This study aimed to perform routine seminal fluid analysis, sperm DNA fragmentation, and sperm function tests at the chromatin maturation level and evaluate pregnancy in the patients passing intrauterine insemination before starting Intrauterine Insemination (IUI) method. Materials and Methods: In this prospective study, 111 couples who underwent Intrauterine Insemination (IUI) in unexplained infertility patients were admitted to Al-Farah IVF and assisted reproductive center in Baghdad, Iraq between November 2020 and February 2021 were evaluated. Semen fluid analysis was performed based on (WHO 4th) guiding rules. In addition, Sperm Chromatin Dispersion (halo test) and sperm maturation were performed with Aniline Blue Stain (ABS). Results: Sperm Chromatin Dispersion (SCD) groups were compared in terms of pregnancy outcome;the positive pregnancy rate was found to be above in the normal SCD groups (p = 0.0005). In addition, Aniline Blue Stain (ABS) groups were compared in the terms of pregnancy outcome;the positive pregnancy rate was found to be higher in the normal ABS group (p = 0.017). Conclusion: Our study showed that the use of DNA fragmentation (SCD) and sperm maturation tests (ABS) together with routine semen analysis in intrauterine insemination cases will make a significant contribution to the prediction of Intrauterine Insemination (IUI) increased results. So, these results indicate a defect in the effect of DNA fragmentation on the outcome of intrauterine insemination.

Artificial Insemination of Cherry Valley Ducks with Muscovy Ducks

[Objective] To explore artificial insemination technique for production of mule ducks. [Method] Female Cherry Valley ducks were artificially inseminated with semen collected from male Muscovy ducks by massage method and vagina-insemination method to investigate the effects of insemination dose, insemination interval, insemination time and diluents on fertilization rate. [ Result ] The average fertilization rate was only 39.58%, when the female Cherry Valley ducks naturally mated with the male Muscovy ducks. However, it was increased to 74.79% by artificial insemination. The fertilization rate was 75.24% after semen was diluted by PBS buffer, while it was 75.16% after semen was diluted by Lake＇s buffer; however, there was not significant difference between the fertilization rate of the diluted semen and that of fresh semen （74.10%）. After semen was respectively diluted by PBS buffer and Lake＇s buffer and then stored at 5 ℃ for 24 h, the fertilization rate was low, respectively 23.76% and 34133%. [ Conclusion] Artificial insemination technology can reduce insemination dose and increase fertilization rate in production of mule ducks.

Study on Key Technique of Artificial Insemination for Silkworm,Bombyx mori

[Objective] The aim of this study was to investigate the efficient technique of artificial insemination for silkworm. [Method] Sperms were extracted from bursa copulatrix of female moths mated for 30 min through extruding and centrifugal method, and then the semen was injected into other virgin moths with trypsinase. [ Result] A high-effective collection technology of spermatids from silkworm was established successfully, 50 μl semen could be collected by only one person in each hour. The survival rate of spermatids was over 80% in vito after collected from bursa copulatrix, while the obtained semen was quite pure and the average fertilization rate of silkworm was 76,5%. [ Conclusion] The establishment of high-effective semen extraction technique of silkworm provides the technical basis for studies on other related techniques for silkworm sperm.

Efficiency of Artificial Insemination in Giant Pandas at the Wolong Breeding Center

The goal of the giant panda ( Ailuropoda melanoleuca ) breeding program is to develop a self sustaining,genetically diverse population.Due to the common problems about sexual incompatibility and a limited number of captive born males that breed naturally,artificial insemination (AI) has become a critical genetic management tool.It is common practice,however,to combine natural mating and AI using semen from non breeding males.From 1998 to 2000 at the Wolong breeding facility,12 of 18 (66.7%) females produced 20 cubs following combined natural mating and AI.The objective of this study was to determine the efficiency of AI without natural breeding.In 1998 and 2000,seven females were anesthetized for transcervical AI on two consecutive days.Ejaculates from six males were collected by electroejaculation,diluted in an egg yolk diluent containing 0% or 4% glycerol and used either fresh or following cold storage at 4℃ (for 24 or 48 h) or cryopreservation using the pellet freezing method.Mean (±SEM) ejaculate traits in six male sperm donors were:ejaculate volume,3.3±0.5 ml;sperm concentration,1,429.8±235.4×10 6/ml;sperm motility,81.7±2.1%;progression (0～5,5=best),3.1±0.1;and normal sperm,79.3±9.2%.For AI (n = 14) in seven females,mean inseminate traits were:spermic volume inseminated,2.4±0.3 ml;sperm motility,73.5±2.9%;progression,2.5±0.1;and total motile sperm inseminated/AI,684.2±118.2×10 6.Four of seven (57.1%) females became pregnant and produced five cubs of which four survived.Mean gestation and litter size was 131.5±9.7 days and 1.3±0.3 cubs/litter,respectively.These results indicate that the efficiency of AI is sufficient for recovering valuable genes from non breeding individuals to enhance genetic diversity in the ex situ population of giant pandas.

Double versus single homologous intrauterine insemination for male factor infertility： a systematic review and meta-analysis

Male factor infertility affects 30%-50% of infertile couples worldwide, and there is an increasing interest in the optimal management of these patients. In studies comparing double and single intrauterine insemination （IUI）, a trend towards higher pregnancy rates in couples with male factor infertility was observed. Therefore, we set out to perform a meta-analysis to examine the superiority of double versus single IUI with the male partner＇s sperm in couples with male factor infertility. An odds ratio （OR） of 95% confidence intervals （CIs） was calculated for the pregnancy rate. Outcomes were analysed by using the ManteI-Haesel or DerSimonian-Laird model accordingto the heterogeneity of the results. Overall, five trials involving 1125 IUI cycles were included in the meta-analysis. There was a two-fold increase in pregnancies after a cycle with a double IUI compared with a cycle with a single IUI （OR. 2.0; 95% CI. 1.07-3.75; P〈O.03）. Nevertheless, this result was mainly attributed to the presence of a large trial that weighted as almost 50% in the overall analysis. Sensitivity analysis, excluding this large trial, revealed only a trend towards higher pregnancy rates among double IUI cycles （OR. 1.58; 95% CI. 0.59-4.21）, but without statistical significance （P=0.20）. Our systematic review highlights that the available evidence regarding the use of double IUI in couples with male factor infertility is fragmentary and weak. Although there may be a trend towards higher pregnancy rates when the number of IUIs per cycle is increased, further large and well-designed randomized trials are needed to provide solid evidence toide current clinical practice.

Successful pregnancy and birth after intrauterine insemination using caput epididymal sperm by percutaneous aspiration

<abstract>Aim: To manage male infertility with obstructive azoospermia by means of percutaneous epididymal sperm aspiration (PESA) and intrauterine insemination (IUI). Methods: Ninety azoospermic patients with congenital bilateral absence of the vas deferens (BAVD, n=58) or bilateral caudal epididymal obstruction (BCEO, n=32) requesting for fine needle aspiration (FNA), PESA and IUI were recruited. The obstruction was diagnosed by vasography and determination of the fructose, carnitine and alpha-glucosidase levels in the seminal fluid. Results: The mean sperm motility, density, abnormal sperm and total sperm count of the caput epdidymis were 16 %±22 %, (12±31) ×106/mL, 55 %±36 % and (16±14)×106, respectively. In the 90 couples, a total of 74 PESA procedures and 66 cycles of IUI were performed. Three pregnancies resulted, including one twin pregnancy giving birth to two healthy boys, one single pregnancy with a healthy girl and another single pregnancy aborted at week 6 of conception. The pregnancy rate per IUI cycle was 4.5 %. Conclusion: The birth of normal, healthy infants by IUI using PESA indicates that the caput epididymal sperm possess fertilization capacity. The PESA-IUI programme is a practical and economical procedure for the management of patients with obstructive azoospermia.

THE INSEMINATION OF GOLDFISH(CARASSIUM AURATUS) OOCYTE MATURED IN VITRO

Full maturation of goldfish oocyte was induced in vitro by 17 a-hydroxy-20B-dihydroprogesterone. The oocyte maturation involves GV migration to the periphery of the oocyte and germinal vesicle breakdown (GVBD). In the experiment, incubation duration for GVBD varied in different broods of oocytes. Generally, if the duration for GVBD was shorter than 6 h, oocytes would have a better chance to survive after maturation and insemination. The maturation of nucleus (GV) and cytoplasm are not synchronous. Cytoplasm maturation occurs several hs after GVBD. Oocytes inseminated 8-9 h after GVBD have the highest fertilizing and hatching rate. Fertilized ova matured in vitro can develop to sexually mature adults capable of reproduction.

A new device for deep cervical artificial insemination in gilts reduces the number of sperm per dose without impairing final reproductive performance

Background: The aim of this study was to evaluate the reproductive performance of a new artificial insemination(AI) device specifically designed for gilts(Deep cervical AI, Dp-CAI) by means of which the sperm is deposited deeply in the cervix(8 cm more cranial than in traditional cervical insemination-CAI). New AI techniques have arisen in recent decades in the porcine industry, such as post-cervical artificial insemination(PCAI), which involves depositing the sperm in the body of the uterus [through a catheter(outer tube)-cannula(inner tube)] rather than by CAI. Although the PCAI method has been successfully applied in farm conditions to reduce sperm doses without impairing the reproductive performance, this technique has limitations in gilts mainly because of the difficulty involved in introducing the inner cannula through the cranial part of the cervix. For this reason, the Dp-CAI method described herein may be considered as an alternative to CAI and PCAI methods in gilts.Results: Gilts were divided in two experimental groups: 1) Dp-CAI: gilts(n = 1166) inseminated using 1.5 × 109 sperm/45 m L;2) CAI(as a control group): gilts(n = 130) inseminated using 2.5 × 10~9 sperm/85 mL. The Dp-CAI method was successfully applied in 88.90% of the gilts, with no differences detected between gilts with 1 or 2 previous oestrus cycles, although the catheter could be introduced more deeply in 2 oestrus gilts(P < 0.05). As the length of the insemination device that could not be introduced increased(at the moment of insemination), so the success rate of the Dp-CAI device fell, as did the total number of piglets born. When the reproductive output in CAI and Dp-CAI was compared, none of the parameters analysed [pregnancy and farrowing rates(%), and number of piglets born(total and live)] showed significant differences.Conclusions: The use of the Dp-CAI technique provides a new AI method as an alternative to CAI and PCAI for pigs. The device, especially designed for gilts, was used with a high degree of success reducing conventional sperm doses without impairing reproductive parameters.

Ovarian pregnancy rupture following ovulation induction and intrauterine insemination:A case report

BACKGROUND Ovarian pregnancy after assisted reproductive technology treatment has rarely been reported;ovarian pregnancy following intrauterine insemination(IUI)is even rarer,and only nine cases have previously been reported.CASE SUMMARY We report a case of ovarian pregnancy rupture after ovulation induction and IUI.The patient presented with bilateral lower abdominal pain and was referred to the emergency department.Ultrasound examination revealed ovarian pregnancy and intraperitoneal bleeding.Laparoscopy revealed an ovarian pregnancy with hemoperitoneum,which was subsequently removed.Pelvic adhesions were detected intraoperatively,which were treated immediately.The patient spontaneously conceived an intrauterine pregnancy 3 mo later,which was ongoing at the time of writing this study.CONCLUSION Close attention should be paid to any history of pelvic inflammatory disease before commencing IUI treatment,and patients with such a history should be closely followed up after IUI.Early measurement of serumβ-human chorionic gonadotropin levels and ultrasonic examination are essential for timely diagnosis of ovarian pregnancy after ovulation induction and IUI to avoid more serious complications.

Treatment of Infertile Women with Unilateral Tubal Occlusion Diagnosed by Hysterosalpingography:The Role of Intrauterine Insemination

Summary:The optimal assisted reproductive treatment strategy for infertile women with unilateral tubal obstruction remains uncertain.To investigate the role of intrauterine insemination(IUI)in the treatment of infertile women with unilateral tubal occlusion,the data of 148 couples were retrospectively collected and analyzed.Seventy-eight infertile women with unilateral occlusion diagnosed by hysterosalpingography(HSG)were categorized as the study group and 70 others with unexplained infertility as the control group.The study group was divided into a proximal occlusion subgroup and a mid-distal occlusion subgroup for further analysis.The main outcomes,namely the clinical pregnancy rate(CPR),ongoing pregnancy rate(OPR),and live birth rate(LBR)per cycle,were analyzed.Our results showed a tendency of lower CPR,OPR,and LBR in the study group than in the control group,without statistical significance.Further investigations revealed that the unilateral proximal occlusion subgroup had similar CPR,OPR,and LBR as the control group,while the unilateral mid-distal occlusion subgroup had significantly lower CPR(5.1%vs.20.0%,P=0.035),OPR(5.1%vs.20.0%,P=0.035),and LBR(5.1%vs.20.0%,P=0.035)than the control group.In conclusion,the clinical outcomes of IUI were worse in patients with unilateral tubal occlusion than in those with unexplained infertility.This might be primarily caused by the worse outcome of patients with unilateral mid-distal tubal occlusion instead of proximal occlusion.

Factors Influencing the Superovulation and Artificial Insemination of Sheep

[Objective] This study aimed to find out a method for low-cost and highly efficient sheep superovulation treatment and artificial insemination. [Method] The factors those probably influencing the results of conventional superovulation and insemination, such as combination of FSH hormone and sponge suppository, estrus interval, number of insemination, and ram individuals were analyzed. [Result] The combination of sponge suppository and FSH produced in Beijing exhibited the poorest effect to superovulation, significantly worse than that of other combinations （P0.01）. The FSH produced in Ningbo, combined with sponge suppository or CIDR produced better effect to superovulation. The superovulation effect was better when the interval from the last FSH injection to estrus was 12 h, significantly better than that when the interval was 36 h （P0.01）; and there was no difference in the superovulation results when the interval was 0, 12 and 24 h. The pregnancy rate of two artificial inseminations was significantly higher than that of only one insemination （P0.01）. Rams themselves had significant influence on fertilization results. [Conclusion] The combination of domestic FSH and domestic sponge suppository cost much less and dose not reduce the superovulation results. Better fertilization result can be obtained if the ewes are inseminated twice with the sperm those gave high pregnancy rate.

Estrus Synchronization and Artificial Insemination with Fresh and Chilled Semen in Assaf Ewes

This paper aims to study the efficiency of two short-term progestagen (FGA vs. MAP) + eCG treatments in estrus synchronization and artificial insemination (AI) with fresh or chilled semen in Assaf ewes fertility rate. All ewes received a subcutaneous implant of exogenous melatonin 45 days before been treated with short-term progestagens + eCG. By June 1st, ewes were divided in two groups: half was treated with an intravaginal sponge impregnated with 20 mg of FGA and the other half with an intravaginal sponge impregnated with 60 mg of MAP. Progestagen treatments lasted for 6 days. At sponge withdraw, all ewes were injected with 750 IU of eCG. Ovarian activity was assessed by plasmatic progesterone levels before and after progestagens + eCG treatment. Semen was collected by electro ejaculation and extended with Andromed? or OviXcell?. AI was performed 55 hours after eCG administration with fresh or chilled semen. During AI several factors were assessed: vagina mucosa color and lubrication, external cervical Os type, cervical mucous viscosity, semen deposition place and seminal cervix outflow. Semen was deposited as deep as possible without distress or trauma cervix mucosa. All Assaf ewes presented cyclic activity before progestagen + eCG treatments (2nd fortnight of May). Short-term progestagen + eCG treatments were equally efficient (100.0%). About 76.5% of Assaf ewes were pregnant 41 days after AI. Fertility rate was influenced by external Os type, semen deposition place and seminal cervix outflow. However, this rate was not conditioned by vaginal color or lubrication, cervical mucus viscosity, semen preservation technic and semen extender.

Clinical pregnancy rate of women with unexplained infertility with or without cervical mucus aspiration before intrauterine insemination: A randomized controlled trial

Objective:To detect effect of removing cervical mucus before performing intrauterine insemination(IUI)on pregnancy rate in patients with unexplained infertility.Methods:The randomized controlled trial was conducted in Infertility Division of Department of Obstetrics and Gynaecology of a tertiary care hospital.Totally 80 patients of unexplained infertility were recruited.By computer generated block randomization in block size of 4 and 6,patients were randomly allocated at time of starting ovarian stimulation into the cervical mucus removal group or the non-removal of cervical mucus group before IUI,40 in each group.Ovarian stimulation with clomiphene 100 mg from day 2-6 of menstrual cycle along with human menopausal gonadotropin 150 IU was given alternate day starting from day 7.Follicular monitoring was done and further doses given as per response;trigger was planned when 1-3 follicle reach a diameter of>18 mm.IUI was planned after trigger.IUI was done as per the group allocated.Mucus cleaning was done in the cervical mucus removal group by aspirating mucus with IUI syringe and sterile cotton swab before IUI.The primary outcome was clinical pregnancy rate.Number of difficult IUIs and cycle cancellation due to ovarian hyperstimulation were also noted.Results:IUI was not done in 4 patients due to hyperstimulation.Pregnancies per IUI cycle occurred in 7.9%(3/38)in the cervical mucus removal group and 21.1%(8/38)in the non-removal of cervical mucus group.There was no statistically significant difference in clinical pregnancy rate between two groups(P=0.19).Conclusions:There is a trend towards a lower clinical pregnancy rate with removal of cervical mucus before IUI in women of unexplained infertility though the difference is not statistically significant.Further studies with large sample size need to be done on this intervention.

Morphology of Gametes and Insemination in the Vestimentiferan <i>Riftia pachyptila</i>

Ultrastructure of gametes (sperm and eggs) of vestimentiferan tubeworms and external-internal insemination by means of spermatozeugmata in Riftia pachyptila were described. The spermatozoa of Riftia are threadlike, about 130 μm long, and have a diameter of about 0.7 μm, narrowing to 0.2 μm in the apical portion of the macrodome, and pointed at the end of the tail. Oocytes are produced by the ovaries at the first meiotic prophase stage. The early oocytes are small, hardly exceeding 10 μm in diameter, spherical cells with a poorly differentiated cytoplasm and large nuclei with a nucleolus. Completely formed oocytes reaching up to 130 μm in diameter leave the ovary, their germinal vesicle is unresorbed and has a nucleolus. They are coated by a yolk membrane of 1.2 μm. The eggs enter the oviduct, move along, and accumulate in its expanded anterior portion, the ovisack. The sperm is released in seawater as sperm packages, each having the shape of a torch. Then sperm moves to females and sperm packages at the posterior end of the oviduct surrounding of eggs. Inside the female tube, spermatozoa and, possibly, yet unsplit sperm packages, invade the oviducts through genital openings, where the unfertilized eggs are already present in the terminal portion of the eggsack.

Artificial Insemination Service Efficiency and Constraints of Artificial Insemination Service in Selected Districts of Harari National Regional State, Ethiopia

The study was conducted to evaluate efficiency of artificial insemination (AI) service and constraints of AI service selected Districts of Harar National Region State, Ethiopia. A total of 320 dairy cows were randomly selected from six districts of Harari region;Jin’Eala, Shenkor, Hakim, Dire-Teyara, Aboker, Sofi. Data on dairy cattle management, artificial insemination (AI) service efficiency and constraints of AI service were generated using structured and semi-structured questionnaire. Forty three straws of frozen semen was sampled from the regional AI service centre, thawed and evaluated at the region level for its quality (motility, viability and morphology) following standard procedures. The overall mean percentage of frozen semen motility at regional level was 49.6. Semen production period (batch) and Breed (exotic blood level) had no effect on frozen semen motility. The mean percentage of viable (live) spermatozoa was 58.3. Sperm viability was not significantly influenced by Semen production period (batch) and, breed (exotic blood level). The overall mean percentages of major and minor sperm morphological defects were 5.6 and 21.8, respectively. Frozen sperm major morphological defects were significantly affected (p < 0.05) by Semen production period (batch), however sire breed has no effect (p > 0.05) on frozen sperm major morphological defects. Frozen sperm minor morphological defects were not significantly affected (P > 0.05) by both semen production period (batch) and sire breed (exotic blood level). The mean number of service per conception (NSC) in the current study was found to be 1.6. It was not significantly affected by previous season of calving, previous year of calving and parity. Non-return rate value of Harari region AI service center was 48.1%. Major constraints of AI service delivery system in the study area were feed shortage, problem in heat detection, service charge for AI, distance from AI service centre and husbandry problem. Additional shortage of input for AI service activity particularly semen and liquid nitrogen was reported as constraint of artificial insemination service in the study area, which interrupt smooth delivery of AI service.

Assessment of Artificial Insemination in Camel

The objective of this review is to confer semen collection and processing, and semen deposition technique in camel. Artificial insemination is an important technique to ensure rapid genetic improvement in camels. The use of AI has been reported in camel, although insemination trials are rare. The widely accepted methods of semen collection include electro ejaculation and artificial vagina (AV), but flushing of the epididymis with saline solution can also be used as an alternative. Depending on the method of semen processing, semen is usually used in raw condition or after extension. Whole semen is used within minutes or after few hours in the fresh raw method. In short-term preservation or liquid semen (within a few hours or days) and long-term preservation or frozen semen (months or years), extension of the semen ejaculate is carried out by adding extenders which is required in more efficient use of AI. Semen is extended under different temperatures (30°C, 25°C or 4°C), in short-term preservation. Cryopreservation is used to carry out long-term preservation. Different freezing procedures are represented by packaging methods such as ampoules or in plastic straws with different volumes (0.25, 0.5 or 4 ml) and pellets. The best time for insemination can only be determined by rectal palpation of the ovaries and/or ultrasonography. The other alternative is to inseminate at known intervals following induction of ovulation by hormonal treatment with human-chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (Gn-RH). The semen should be deposited into the uterus at least 24 hours after the onset of ovulation. Pregnancy rates depend on the semen extender, site of deposition and number of sperm deposited. Blood or milk progesterone assays, rectal palpation, and ultrasonic image detection of pregnancy are commonly used approaches of pregnancy diagnosis in camel.

Effect of administration of phenylephrine immediately after low dose insemination on pregnancy rates in mares

There is considerable pressure on equine veterinarians to achieve good pregnancy rates with very small doses of semen. Phenylephrine administration in the rabbit increased numbers of oviductal, uterine, and cervical sperm, myometrial contractions, and fertilized ova after low dose insemination. The use of phenylephrine to enhance uterine contractility and fertility has not been investigated in the mare. Thus, the objective of this study was to determine if phenylephrine administration would result in clinically acceptable pregnancy rates in mares bred by low dose insemination. The hypothesis (Ha) was that pregnancy rates would be significantly higher in mares receiving phenylephrine compared to saline controls. Six pony mares and eight horse mares were enrolled in this study. Mares were inseminated within 24 hours of ovulation with 30 million progressively motile spermatozoa from a single fertile stallion. Immediately following insemination, mares were administered either phenylephrine (0.06 mg/kg) or 1mL of saline via IV injection. Pregnancy status was determined 14 days following ovulation via transrectal ultrasonography. Pregnancy rates in phenylephrine treated mares were 44% (4/9) while 22% (2/9) in saline-treated mares (P > 0.05).

Comparative Study of Two Methods of Induction of Estrus and Fertility Following Artificial Insemination in Azawak Zebu in Niger

A comparative of two induction methods of estrus induction and fertility has been carried out on 28 females Azawak zebu in Niger. This study mains chiefly and identifying the most effective method for better inseminations. The females have been divided into two sets following two intra-vaginal devices used. Two sub-sets of 7 females have been formed according to the PMSG dose associated with the treatment. Two inseminations have been carried out. The results are as follows： response to the induction： PRIDe, 57.14%; CIDR-B, 61.53%. Fertility rate： PRIDe, 28.57%; CIDR-B, 38.46%. There has been no significant difference to the estrus induction and fertility, between the PRIDe and the CIDR-B synchronization. Since the two methods virtually lead to the same response rate, the stock breeder can choose one of the methods depending on the cost and by paying attention to the feeding and less stressful factors.

Comparison of Two Insemination Programs in Synchronized Early Postpartum Zebu Cows under Tropical Conditions: An Economic Appraisal

To evaluate an artificial insemination program in postpartum Bos indicus cows and by using deterministic models, to estimate the possible economic advantages of insemination by appointment over detected estrus, sixty-three multiparous animals were synchronized using a progestagen device inserted at day 31 and withdrawn after 9 days (average time for withdrawal was 40.9 ± 6.8 days). Cows were observed continuously from 0700 to 1800 during 72 h. The percentage of animals detected positive to estrus by riding behavior was 43.4%, transrectal palpation, 22% and heat detector patches, 4.6%. The percentage of cows ovulating as evidenced by progesterone samples taken at 9 and 11 days after the average estrus response was 73%. The economical assessment by using the values obtained in the present study afforded that the cost of semen, ovulation rate and fertility point to a definitive advantage of using AI at fixed time over a program based on estrus detection.