Artificial Insemination Program Research Articles

Assessment of Frozen Semen Quality through Foldscope Microscopy- A Novel Application of Frugal Science to Reduce the Infertility Rate

Background: Quality determination of frozen semen before using for Artificial Insemination (AI) in cattle is of paramount importance. The success of cattle AI programs is largely depends on the use of good quality semen and thus assessment of semen quality parameters before AI will improve the conception rate and reduces the loss associated with repeated breeding. Among the various semen quality indicators, sperm motility is one of the important parameter and it should be evaluated immediately after semen collection (before freezing) and 24 hrs after freezing as per minimum standard protocol in frozen semen production. Though the motility is a major determinant of spermatozoa ability to reach the site of fertilization and it is affected by cryopreservation and subsequent poor cold storage facilities, motility is not frequently evaluated under field conditions. In the current scenario, many of our government AI sub-stations in remote villages are not equipped with microscope facility for semen quality evaluation before AI. Methods: In this study, we used foldscope, an origami-based paper microscope which give optical quality similar to conventional microscopes (magnification of 140X and 2-micron resolution), to evaluate the frozen semen motility at field level. In this study, the motility of spermatozoa was observed under foldscope and concluded that foldscope is very useful to asses the motility befor AI and improve the fertility in dairy animals. Result: We revealed that, utility of foldscope to assess the motility of spermatozoa was evaluated under field conditions and observed that 46% of sperms were motile. Further, evalaution of sperm motility before AI is not very common practice due to lack of microscope in many AI centres. Therefore, foldscope will be very useful at field conditions to avoid AI using poor quality semen and subsequent loss associated with repeat breeding problems.

Sperm function and oxidative status: Effect on fertility in Bos taurus and Bos indicus bulls when semen is used for fixed-time artificial insemination

Semen quality is one of the criteria used for the selection of bulls with relatively greater fertility. In addition, bull fertility depends on the integrity and function of all sperm structures. The aim of this study, therefore, was to determine associations when there was conducting of conventional and functional techniques for the evaluation of sperm samples from bulls with known fertility history as determined when semen from these bulls was used for fixed-time artificial insemination programs. The study was designed in a 2 × 2 factorial arrangement, with one factor being breed (Angus x Nellore) and the other fertility (greater x lesser). Greater fertility groups were composed of ten Angus and 11 Nellore bulls, while lesser fertility groups were composed of ten Angus and seven Nellore bulls. Sperm were analyzed, in four cryopreserved distinct batches for each animal, for morphology, kinetics, plasma and acrosomal membrane integrity, mitochondrial activity and mitochondrial membrane potential, DNA integrity and oxidative status. There was no difference in characteristics commonly used in sperm quality conventional analysis. The results from functional analysis indicated an important association between mitochondrial dysfunctions, oxidative stress, and damage to sperm structures in lesser fertility bulls. Greater fertility bulls had greater sperm quality and indicators of functional cell structures. The associations, when there were evaluations using different techniques, indicate the importance of evaluation and correlation between different sperm functions to understand effects of distinct parameters on sperm fertilization capacity.

Improving Animal Production, Productivity and Economic Gain to the Farmers through Increasing Coverage of Artificial Insemination in India

Data from authentic sources i.e. Government Annual Reports, published research papers and various cooperative organizations of the country were collected and analyzed using ARIMA (Auto Regressive Integrated Moving Average), ADF (Augmented Dickey-Fuller Test) to arrive at definite conclusions for the scientific fraternity in the field of Animal Reproduction. The sole objective for giving information is to get the momentum of developmental activities further in one of the most important technologies i.e. Artificial Insemination (AI) which has changed the country from a milk deficit to a milk surplus and taken the nation on top of the milk producing countries of the world with 209.9 million tones followed by USA, Pakistan, China and Brazil. Presently India is performing 81.9 million AI’s annually with a lower conception rate of about 35% in 2021. Per capita milk availability per day, Productivity, AI coverage, Expansion of AI, Conception rate, Milk production growth rate, Milk processing status, Milk prices and Farmer’s gain per litre of milk produced have been 427 ml, 5.65 litres, 30%, 16 million farmers, 35%, 5.8%, 20.50% of the total milk produced in the country, Rs 35/litre for cows and Rs.52 /litre for buffaloes, respectively. Hence, the profitability of the fluid milk for farmers is negligible considering the current market infrastructure in the country. It is concluded from the study that the AI programme must be continued in campaign mode till it reaches about 80% of the breedable bovine population with a continuous programme of producing High Genetic Merit (HGM) bulls in the country and their availability to semen stations for semen production which will answer the future need of the nation.

Spatial variation of sheep and goats in Sulaimaniyah province

This study is based on studying the geographical distribution of sheep and goats in the Sulaymaniyah governorate and analyzing their variance according to the districts، as sheep and goats are among the most important animals raised in Sulymaniyah to take advantage of their meat، dairy and wool، and on it this study tries to reveal the variables that explain sheep and goats geographically، And showing the effect of geographical factors on that distribution، as the geographical distribution of sheep and goats is affected by geographical factors (Physical and Human ) and by the population distribution , As the surface of the governorate is characterized by swaying and complexity in the northeastern parts, and this terrain permeates areas of mountain valleys plains, and the suitability of climatic conditions, which is characterized by moderate temperatures and winter rains that are sufficient for dry cultivation and intensive natural plant growth. However, the animal wealth suffers many problems, which requires several Among other things, improving animal breeds and working to increase the productivity of local animals by developing an artificial insemination program and paying attention to veterinary cadres and providing fodder through the cultivation of some fodder crops, through which the development and advancement of sheep and goat raising.

Pregnancy Rate in Synchronized Iraqi Awassi Ewes Inseminated Artificially and Naturally

This study was carried out to evaluate the efficacy of imported Australian frozen semen straws inachieving successful artificial insemination program in estrus synchronized ewes. This study conductedon twenty-one Awassi ewes, aged 2 - 4 years, and four fertile rams (two rams for natural mating and twofor detecting of estrous by using apron) in Baghdad province (Rumintia Research station, departmentof animal resource research, state Board for Agriculture Research, Ministry of Agriculture/ AbuGhraib district), for the period from November 2020 to March 2021. Pregnancy diagnosis was doneby ultrasound to detect reproductive status of the ewes, then all non-pregnant ewes were synchronizedby using vaginal sponges (60 mg of Medroxy acetate Progesterone / MAP) for 10days plus 500IU ofPregnant Mare Serum Gonadotropin (PMSG) in day 10, all animals were divided randomly into threeequal groups each of seven ewes according to the type of insemination, G1 (1straw) and G2 (2 straws/8 hrs. interval) and G3 serviced naturally by fertile rams then the females were isolated from the males.The response of animals to hormonal treatment was 21, with a response rate of 100% in all groups withno significant difference with mean durations of response recorded 63.6± 11.7, 66.7± 12.2, and 62.8±10.7 for the three groups, respectively. The pregnancy rate with single, double AI and natural matingwas 41.86 and 71.41 and 71.42 percent, respectively with a highly significant difference (P<0.01)between G1 and G2. In conclusion, under field conditions, double AI with 20 ×106 sperm proved to besuitable for generating high pregnancy rates in Iraqi Awassi ewes.

Hydroxy-selenomethionine as an organic source of selenium in the diet improves boar reproductive performance in artificial insemination programs.

This study aimed to compare different selenium (Se) sources in the diet on boar's semen quality and fertility. For this, 28 boars aged 8 to 28 mo were fed with the following dietary treatments for 95 d: 0.3 mg Se/kg as sodium selenite (SS; n = 14) and 0.3 mg Se/kg as hydroxy-selenomethionine (OH-SeMet; n = 14). During this period, two experiments were carried out. In experiment 1, the semen of all boars was evaluated every 2 wk. Raw semen was initially evaluated for the processing of seminal doses, which were stored at 17 °C for 72 h, followed by sperm quality assessments. Furthermore, Se concentration and glutathione peroxidase (GPx) activity were measured in the seminal plasma. In experiment 2, 728 females were inseminated weekly with seminal doses from boars of the different experimental groups to further assess in vivo fertility and litter characteristics. Results demonstrated that boars fed OH-SeMet had more Se in their seminal plasma (P < 0.05), showing the greater bioavailability of the organic source in the male reproductive system. Moreover, boars fed OH-SeMet tended (P < 0.10) toward a higher total sperm count in the ejaculate (66.60 vs. 56.57 × 109 sperm) and the number of seminal doses (22.11 vs. 18.86; 3 × 109 sperm/dose) when compared with those fed SS. No effect of the dietary treatments was observed on GPx activity in seminal plasma (P > 0.05) as well as on raw and stored semen quality (P > 0.05). Under in vivo conditions, seminal doses from boars fed OH-SeMet tended (P < 0.10) toward a higher pregnancy rate at weeks 3, 5, and 8, and also resulted in a higher (P < 0.05) percentage of pregnant females in the overall period (99.30 vs. 97.00). In conclusion, the replacement of SS with OH-SeMet in boars' diet can improve sperm production and results in better reproductive performance for them, bringing greater productivity and profitability to artificial insemination centers and commercial pig farms.

The Successful of Artificial Insemination in Bali Cow in Muaro Jambi Regency, Jambi Province

The successful implementation of the artificial insemination (AI) program is a Measurement of the amount reproductive efficiency value that achieved. The value of the efficiency of the successful of artificial insemination (AI) can be assessed by measuring the rate per pregnancy or Service per Conception (S/C), calving distance or Calving Interval (CI) and pregnancy rate or Conception Rate (CR). This research has been carried out in Muaro Jambi Regency from September 11, 2021 to October 01, 2021. This study aims to determine the success of artificial insemination (AI)) in Bali cow in Muaro Jambi Regency and to determine Service Per Conception (S/C), Conception Rate (CR), and Calcing Interval (CI). This research was conducted using a survey method where the sampling method (respondents) was purposive sampling of respondents who has the criteria, namely respondents who had mother cows who had given birth at least 2 times to breeders in Jambi Luar Kota District, Muaro Jambi Regency and were married by artificial insemination (AI). The changes observed were Service per Conception (S/C), calving interval or Calving Interval (CI) and pregnancy rate or Conception Rate (CR). The data obtained were processed. The results showed that the successful of artificial insemination (AI) in Muaro Jambi Regency in the form of Service per Conception (S/C) which was 1,58, calving interval (CI) of 14,05 months and pregnancy rate or Conception Rate (CR). ) ) of 56,14%. It can be concluded that the successful of Synthetic Insemination (SI) in Muaro Jambi Regency can be categorized as having succeeded optimally, it can be seen from the service per concept (S/C), calving interval (CI) and the level of conception (CR).

An Evaluation of Semen Quality of Donor Bulls in the Central Artificial Insemination Station (CAIS), Kundasale, Sri Lanka

Fertility assessment of semen donor bulls used in Artificial Insemination programs is an important step in improving dairy industry in Sri Lanka. A study was conducted to evaluate the fertility of semen donor bulls using semen parameters and respective pregnancy rates. The semen donor bulls (n =21) in the Central Artificial Inseminations Station, Kundasale were selected for the study, and the hypo-osmotic swelling test was performed for both fresh and frozen semen of each bull. Data were analysed using statistical function of Excel software version 2010. Presence of high percentage of hypo-osmotic swelling positive spermatozoa in both fresh and post-thawed frozen semen indicated that all bulls studied were highly fertile. A total of 49255 AIs has been performed in four provinces with an overall pregnancy rate of 28.2%. The highest pregnancy rate of 57.6% was recorded in the Northern Province and the lowest pregnancy rate of 22.5% was recorded in the Central Province. The study revealed that there was no significant difference (p&gt;0.05) in semen quality among individual bulls or among breeds. Al though the semen quality of the bulls was in the acceptable range, the pregnancy rate differed significantly (p&lt;0.05) according to the area. In addition, the overall pregnancy rate was (28.2 %) below the acceptable level. Further studies are required to investigate factors associated with semen quality and the low pregnancy rates observed in some of the areas.

Measurement of the reproductive efficiency of Arabian stallions intended for AI in Algeria

The aim of this study was to determine the reproductive efficiency of Arabian stallions presented at CNIAAG and selected for an artificial insemination (AI) program. Ten Arabian stallions between 8 and 15 years of age were subjected to an analysis of the reproductive parameters. Assessment of sexual behaviour, testicular measurements and appreciation of semen quality collected with the help of artificial vagina was done. There was a significant correlation between the sexual behaviour, the spermatic parameters and the testicular parameters, especially between the number of mounts with the motility and the daily sperm ejaculated (DSP) (r=0.99). The testicular volume total and mounts was highly correlated to the average volume of ejaculate (73.33 ± 60.27 ml) and total Sperm concentration (billions) (r=0.99) which allowed us to produce 38 straws intended for the preservation. Based on the results, it is concluded that there is a positive correlation between (TSW) and motility, the various measurements of testis size were highly correlated with each other; and consequently to predict the fertility of the stallions from the testicular measurements.

Oxytocin in pig seminal plasma is positively related with in vivo fertility of inseminated sows

BackgroundIdentification of relevant in vivo biomarkers for fertility remains a challenge for the livestock industry. Concentrations of the small peptide hormone oxytocin (OXT), involved in male reproductive function and present in the seminal plasma (SP) of several species could be a robust one. This study characterized concentrations of SP-OXT in ejaculates from boars used in artificial insemination (AI) programs aiming to evaluate its relationship with sperm quality variables and in vivo fertility of their liquid-stored AI-semen. Seminal OXT concentrations (ng/mL) were measured in 169 ejaculates from 61 boars of the Duroc, Pietrain, Landrace and Large White breeds using a direct competitive immunoassay test based on AlphaLISA® technology. Ejaculate (ejaculate volume, sperm concentration, total sperm count) and sperm parameters (motility, viability, intracellular generation of reactive oxygen species, plasma membrane fluidity) were assessed at 0 h and 72 h in AI-semen samples stored at 17 °C. In vivo fertility included only 18 Large White and Landrace boars whose AI-semen was used to inseminated > 100 sows and evaluated both farrowing rate and litter size of 3,167 sows.ResultsThe results showed that SP-OXT differed between boars and between ejaculates within boar (P < 0.05) but not between breeds (Duroc, Pietrain, Landrace and Large White). Ejaculates with higher SP-OXT concentration/mL (hierarchically grouped; P < 0.001) had larger volume and came from younger boars (P < 0.05). Ejaculates of boars showing positive farrowing rate deviation exhibited higher (P < 0.05) SP-OXT concentration/mL than those with negative farrowing rate deviation.ConclusionThe SP concentrations of OXT are boar, ejaculate and age dependent, and positively related with ejaculate volume and farrowing rates of liquid-stored semen AI-doses.

Characterization of Dadih: Traditional Fermented Buffalo Milk of Minangkabau

Dadih or dadiah is traditional fermented buffalo milk of Minangkabau, which occurs spontaneously. Dadih is commonly served as ampiang dadih, or other dishes. The microbiota found in dadih are dominated by lactic acid bacteria, and yeasts are also found. The lactic acid bacteria provide functional value, such as antimicrobial, hypocholesterolemic, antimutagenic, antioxidant, and immunomodulatory properties, as well as being the source of γ-aminobutyric acid (GABA) as an anti-stress agent and folate. Nevertheless, many challenges were observed in dadih production, including the limitation of buffalo milk production due to decreasing populations of buffalo in the last two decades, unstandardized dadih production due to the spontaneous fermentation in natural bamboo tubes, and safety problems as no heat treatment is applied in the production of dadih. These problems impede the development of dadih production, thus is it important to improve buffalo cultivation through artificial insemination programs, using different types of milk and pasteurization processes in dadih production, and incubator development to accelerate the fermentation period.

Effect of ovulation synchronization program and season on pregnancy to timed artificial insemination in suckled beef cows

This study was conducted to (i) evaluate the requirement for the administration of GnRH coincident with insertion of a progesterone-releasing intravaginal device (PRID) and (ii) the effect of supplementing with 400 IU eCG at PRID removal on pregnancy per AI (P/AI) in spring and autumn calving suckled beef cows, subjected to a 7-d CO-Synch + PRID timed artificial insemination (TAI) program. Suckled beef cows (n = 1408) on 62 commercial farms were enrolled and randomly assigned to either of three treatments: 1) cows received a PRID and 100 μg GnRH on Day −10, followed by 25 mg PGF2α at PRID removal (Day −3) and 100 μg GnRH 72 h later (Day 0) at TAI (Treatment 1; n: spring = 236, autumn = 248); 2) as Treatment 1, but without GnRH at PRID insertion on Day −10 (Treatment 2; n: spring = 232, autumn = 227); 3) as Treatment 1, but cows also received 400 IU eCG at PRID removal on Day −3 (Treatment 3; n: spring = 233, autumn = 232). At Day −10, ovaries were examined by ultrasonography to evaluate the presence or absence of a corpus luteum (CL) and follicle(s) ≥ 10 mm in diameter. Body condition score (BCS) was assessed on a scale of 1–5. Pregnancy diagnosis was carried out 30–35 d after TAI by transrectal ultrasonography. Data were analyzed using the GENMOD and LOGISTIC procedures of SAS. There was a treatment by season interaction for P/AI (P < 0.001). In spring, overall P/AI was 59.1% (414/701) and was affected by treatment (59.3 v 49.6 v 68.2%, for Treatments 1, 2 and 3, respectively P < 0.05). In contrast, in autumn, overall P/AI (51.5%, 364/707) was unaffected (P > 0.05) by treatment (50.1 v 53.7 v 48.7% for Treatments 1, 2 and 3, respectively). Overall, eCG had a positive effect on P/AI for cows lacking a CL at treatment initiation (P < 0.05). In addition, in cows with low BCS (≤2.25), eCG supplementation tended (P = 0.09) to improve P/AI. Seasonal differences in response to synchronization treatment may be reflective of different management regimens (grazing v confinement) and breed type and remain to be elucidated.

Cryopreservation of seminal vesicle derived spermatozoa from Bombus impatiens and Apis mellifera – Implications for artificial insemination of bumble bees

This study evaluates the efficacy of a cryopreservation protocol for spermatozoa derived from the accessory testis of male Bombus impatiens. It is also the first report of successful cryopreservation of bumble bee spermatozoa. The spermatozoa viability was compared with the similarly treated honey bee spermatozoa derived from its accessory testis. The semen was frozen using a yolk-free non-activating buffer containing dimethyl sulphoxide and stored in liquid nitrogen for 24 h to ~14 days. Thereafter, the frozen samples were thawed rapidly and assessed by staining with live/dead differentiating fluorescent dyes. Semen viability in cryopreserved samples (55.8 ± 14.0%) was significantly different than controls (96.2 ± 10.5%). Similar assessment with A. mellifera resulted in 82.2 ± 7.0% viable cryopreserved spermatozoa versus 99.4 ± 0.1% in controls. A similar proportion of the sperm cells were also capable of motility upon dilution of the extender medium with phosphate buffered saline. The proportion of viable accessory testis derived sperm cells obtained post-cryopreservation was estimated to be sufficient to initiate long term storage and artificial insemination programs.

Effect of melatonin on follicular development parameters in a fixed-timed artificial insemination programme in water buffalo

It is well known that buffaloes have seasonal anoestrus and that the use of melatonin reduces the effects of season in reproduction, articularly among sheep and goats. This study evaluates the use of melatonin on water buffaloes to increase pregnancy rates in a fixed-time insemination programme. The study was conducted on an Argentinian buffalo herd, located in the Corrientes Province, during an unfavourable reproductive season. Artificial insemination cycles were performed in September and December 2018. Sixty animals were selected, and melatonin was administered to 29 females at a dose of 18 mg/50 kg. Ten days after the melatonin implant, ovulation synchronization was started. Animals were inseminated with frozen semen of a single bull. Pregnancy was evaluated by ultrasound 35 days after insemination. The pregnancy rate of the two repetitions was 34.62% for September and 6.4% for December (P=0.007). No significant differences were found in the parameters associated with follicular development and formation of the corpus luteum. Analysis of the effects of melatonin on the two replicates showed that there was no statistically significant effect of ovarian response regarding the analysed follicular development parameters. There was also no effect on pregnancy rates (17.85% vs. 20.68%; P=0.15), or on follicular development for treatment and control. In conclusion, this study was not able to demonstrate an effect of melatonin on the ovarian response of buffaloes as reported by other authors. Other factors, such as environmental conditions of subtropical areas and species specificities, may have a more significant effect on buffalo endocrinology. These factors should be evaluated to improve the results of fixed-timed artificial insemination programmes.

Potential semen quality rate of Ongole Crossbred Bulls at Cattle Breeding Station (UPT PT & HMT) Tuban - Indonesia

The variation in semen quality serves to determine the fertility potential of Ongole Crossbred (PO) bulls. Semen quality has a correlation to fertility. Individual motility is one of most important factors determining the success of artificial insemination program. The aims of this research were to mapping the bulls who have high and low fertility potential. This variation is used to determine the composition of molecular marker genes for reproductive traits through the RNA-Sequencing method. 12 PO bulls aged 2–8 years were used in this research. The research parameters were volume, concentration, individual motility, viability, abnormality and sexual behaviour. Sexual behaviour data were analyzed using descriptive methods. Semen quality data were analyzed using an unpaired T-test. The results showed that the bulls code with the highest to lowest motility values were PO-5, PO-2, PO-3, PO-6, PO-4, PO-7, PO-9, PO-8, PO-1, PO-10, PO-11, PO-12, respectively. 4 bulls with the highest motility values and the 4 bulls with the lowest motility values had significant differences (P<0.05). Therefore, it can be concluded that the two populations of PO bulls with the highest and lowest motility value are different. It can be continued with the RNA-Sequencing method to find the gene composition of the spermatozoa.

Influence of Non-conventional Sperm Quality Parameters on Field Fertility in Ovine.

The prediction of the fertilizing ability of a seminal dose continues to be a primary aim in the field of artificial insemination (AI). To achieve this goal, in this study we have included the evaluation of some non-conventional sperm quality markers. A total of 3,906 ewes from 52 different farms were inseminated with 357 refrigerated seminal doses obtained from 45 mature Rasa Aragonesa rams. The same samples were used for sperm quality analysis including membrane integrity, capacitation status, oxygen consumption and apoptotic-like markers such as phosphatidylserine translocation (PS), plasmalemma disorganization/mitochondrial membrane potential, caspase activation and DNA damage. Seminal doses from the breeding (B) season presented higher percentages of intact membrane (IM), non permeant (NP) membrane with high mitochondrial membrane potential (ΔΨm) and IM without PS translocation spermatozoa than those from the non-breeding (NB) season. Therefore, we can conclude that there were less spermatozoa showing apoptotic-like features in the seminal doses from the B than the NB season, although these differences did not affect field fertility. Only the percentage of intact membrane, non-capacitated (IM-NC) spermatozoa showed a significant correlation with in vivo fertility (P = 0.005) and fecundity (P = 0.007) values obtained after cervical AI when all data were evaluated. When the data were sorted by season and distance to the farms where AI was performed, the correlation between the percentage of IM-NC spermatozoa and reproductive parameters increased in the NB season and progressively with remoteness from the farms. Some other sperm parameters, like NP with high ΔΨm, IM sperm without active caspases and DNA-intact spermatozoa, also showed significant correlations with the reproductive parameters in the sorted data. Moreover, the increment in both the percentage of IM-NC and DNA-intact spermatozoa would increase the probability of obtaining a fertility higher than the mean (>52%), as revealed by a multiple logistic regression analysis. In conclusion, we have identified two seminal markers—the percentage of intact membrane, non-capacitated spermatozoa, and DNA intact spermatozoa—which could be used as a test to discard males in AI programs, which is highly important from an economic point of view and can contribute to achieving satisfactory fertility rates.

Investigating Plasma Metabolomic Profiles at the Time of Weaning, Based on Pregnancy Outcome, in Bos Taurus heifers

Abstract The objective of this study was to identify differences in the metabolomic profiles of heifers at the time of weaning based on their subsequent pregnancy outcomes. Angus/Simmental-cross heifers (n = 36) were weighed at weaning and 10ml of blood was collected. The blood plasma and white blood cells (WBCs) were isolated. Heifers were then assessed 30 days prior to artificial insemination (AI) for weight, pelvic area (PA), body condition scores (BCS) and reproductive tract scores (RTS). Reproductively mature heifers underwent an AI program with estrus detection and were then exposed to a bull two weeks after AI. Heifers were categorized into three groups: pregnant by AI, pregnant by natural breeding or open after 3 consecutive estrous cycles. 9 heifers pregnant by AI and 11 open heifers were chosen for metabolomic profiling. Of the 20 heifers selected, there was no difference in weight at weaning (355.6±21.9 kg AI, 364.2±33.3 kg Open, p &amp;gt;0.05), BCS (5.7±0.4 AI, 5.6±0.4 Open, P &amp;gt;0.05), RTS (4.1±0.6 AI, 4.0±0.7 Open, P &amp;gt; 0.05) or PA (173.7±10.8cm2 AI, 175.6±9.1cm2 Open, P &amp;gt; 0.05). Ten metabolites were found to be significantly up or down regulated in the heifers who remained open after three consecutive cycles, when compared to those pregnant by AI. Alanine, cystine, lysine, methionine, tyrosine, tryptophan and valine were down regulated while glycerol, fructose-6-phosphate and ribulose-5-phosphate were found to be up regulated in open heifers (P &amp;lt; 0.05). RNA isolated from WBCs was used to compare the expression of five inflammatory cytokines in the open and pregnant by AI groups (TNFα, IL6, CXCL5, POSTN and MCP1). Inflammatory cytokines were increased in all heifers that remained open after three consecutive cycles (p&amp;lt; 0.05). In summary, the quantity of specific metabolites present within the blood plasma are different at weaning between heifers with differing reproductive potentials. This could potentially be used to develop an assay to aid in selecting replacement females.

The use of fixed time artificial insemination programmes for the use of sexed semen in block calving dairy heifers

In seasonal block calving herds reproductive efficiency can have a significant impact on productivity and profitability. Within this it is key that the nulliparous heifers calve down promptly in the block, and if these heifers can have heifer calves it will expediate genetic gain. There is extensive research into the conception rates of differing protocols and the literature is reviewed to support the choice of protocol used in the subsequent case study. The case study uses a 6-day progesterone protocol with two injections of prostaglandin F2α and sexed semen; it demonstrated acceptable conception rates as well as the variability that can occur between different bulls' semen straws. Finally, the case study assesses the costs and benefits of the synchronisation programme and concludes a cost benefit of £88.55 per heifer.

Use of cooled buffalo semen as a strategy to increase conception rates in fixed-time artificial insemination programs during unfavorable reproductive periods

ABSTRACT The objective of this study was to compare the reproductive efficiency of dairy buffaloes undergoing fixed-time artificial insemination (FTAI) protocols based on progesterone/estrogen (P4/E2) and eCG during unfavorable breeding season using cooled (CS) and frozen semen (FS). A total of 446 buffaloes (&gt; 40 days postpartum) were randomly distributed into four blocks (years): B1-2014 (n = 143), B2-2015 (n = 34), B3-2016 (n = 90), and B4-2017 (n = 179). Each block was subdivided into two (AI with CS and FS using the same ejaculate of each bull). Thus, the block subdivision was as follows: B1 (CS = 71 and FS = 72); B2 (CS = 18 and FS = 16); B3 (CS = 47 and FS = 43); and B4 (CS = 90 and FS = 89). The ejaculates of eight Murrah bulls collected using an artificial vagina were divided into two aliquots: one aliquot was diluted in Botu-Bov® commercial extender and cooled (BB-CS), and the other was diluted in the same extender and frozen (BB-FS). BB-CS aliquots were cooled at 5 °C/24 h using a refrigerator. BB-FS group aliquots were also cooled, and after equilibrating at 5 °C for 4 h, were placed in a 21-L Styrofoam box, 5 cm above the surface of liquid nitrogen. In the afternoon (A) on D0 (2:00 p.m.) the animals received EB 2.0 mg IM (Estrogin®) and an ear implant (CRESTAR® 3.0 mg P4). At D9 (A), the implant was removed, and the animals received eCG 400 IU IM (Folligon® 5000) + Cloprostenol PGF2α 0.530 mg IM (Sincrocio®). At D10 (A), the animals received EB 1.0 mg IM (Estrogin®), and at D12 (8:00 a.m.), AI was performed. At D42, pregnancy was diagnosed via ultrasonography. Total CRs were 48.2% CS and 34.6% FS for years 2014 to 2017, with a significant difference of 13.7% (P&lt;0.05). In conclusion, cooled semen resulted in higher CR than frozen semen in dairy buffaloes under the P4/E2 and eCG FTAI during the unfavorable reproductive season.

SEASONAL VARIATIONS ON SEMEN CHARACTERISTICS OF FATTAILED AND GARUT RAMS UNDER TROPICAL CONDITIONS

This study investigated the influences of rainy and dry seasons on semen characteristics of fat-tailed and Garut rams under tropical conditions. A total of 4 healthy rams (2 fat-tailed rams and 2 Garut rams) aged 3 to 4 years old were used in this study. The semen was collected from each ram during November 2016 to February 2017 (rainy season) and May to August 2017 (dry season). The measurement of semen characteristics including semen volume (SV), sperm concentration (SpC), total sperm (TSp), individual sperm motility (ISM), post-thawing sperm motility (PTSM), and frozen semen production (FSP). The rainy season resulted higher SV (P= 0.021), TSp (P= 0.005), ISM (P= 0.028), and FSP (P= 0.005) than the dry season. On the other hand, fat-tailed rams had higher (P0.001) SV, TSp, and FSP compared to Garut rams. There was no interaction (P0.05) between season and breed on all semen characteristic parameters found in the present study. It can be concluded that the semen collection during the rainy season had a beneficial impact to produce high-quality semen for artificial insemination program than in the dry season. Fat-tailed rams have better semen characteristics compared to Garut rams.