Semen Sex Research Articles

Reproductive Biotechnology Tools as a Game Changer for the Dairy Sector: The Case of Sexed Semen and Estrus Synchronization to Produce Seedstock Dairy Heifers

Human curiosity about the sexual orientation of living things has a long history. For thousands of years, livestock owners wanted to find a suitable way to predict the sex of the progeny to be born for their herds on their farm. Thanks to the development of semen sexing technology, animal breeding has undergone a revolution, which allows farmers to control the sex of their offspring. Sexed semen enhances overall productivity and also assists farmers in meeting the rising demand for high-quality dairy animals by enabling them to selectively generate seedstock female calves. The technology is a one-stop solution to enhance breed improvement especially in a country like Ethiopia where 97 percent of the cattle population is indigenous, which is not selected for milk production and results in undernourishment for animal source origin diet, including milk and meat. The benefits of using sexed semen include sex selection, improved genetic selection, enhanced breeding effectiveness, better control over herd dynamics, greater financial gains, environmental sustainability, and improved animal welfare. Hence, with the finding of this study, an overall result of a 98% response rate 95% female skewness, and 79% conception rate was recorded after being inseminated with sexed semen. The finding of the response rate is closer to the results reported by another researcher, while the average conception rate is comparatively higher. This could be due to careful animal selection, the use of fertile quality semen, proper heat detection, and inseminating at an optimum window of time. In general, from the piece of this study, it is possible to foresee and conclude that the adoption and application of sexed semen technology is a groundbreaking and game-changer technology for the dairy industry in a country like Ethiopia, which overcomes the limitations of improved crossbred dairy cattle, replacement heifers, and high milk prices on the one hand, a shortage of grazing land, ...

Reproductive Biotechnology Tools as a Game Changer for the Dairy Sector: The Case of Sexed Semen and Estrus Synchronization to Produce Seedstock Dairy Heifers

Human curiosity about the sexual orientation of living things has a long history. For thousands of years, livestock owners wanted to find a suitable way to predict the sex of the progeny to be born for their herds on their farm. Thanks to the development of semen sexing technology, animal breeding has undergone a revolution, which allows farmers to control the sex of their offspring. Sexed semen enhances overall productivity and also assists farmers in meeting the rising demand for high-quality dairy animals by enabling them to selectively generate seedstock female calves. The technology is a one-stop solution to enhance breed improvement especially in a country like Ethiopia where 97 percent of the cattle population is indigenous, which is not selected for milk production and results in undernourishment for animal source origin diet, including milk and meat. The benefits of using sexed semen include sex selection, improved genetic selection, enhanced breeding effectiveness, better control over herd dynamics, greater financial gains, environmental sustainability, and improved animal welfare. Hence, with the finding of this study, an overall result of a 98% response rate 95% female skewness, and 79% conception rate was recorded after being inseminated with sexed semen. The finding of the response rate is closer to the results reported by another researcher, while the average conception rate is comparatively higher. This could be due to careful animal selection, the use of fertile quality semen, proper heat detection, and inseminating at an optimum window of time. In general, from the piece of this study, it is possible to foresee and conclude that the adoption and application of sexed semen technology is a groundbreaking and game-changer technology for the dairy industry in a country like Ethiopia, which overcomes the limitations of improved crossbred dairy cattle, replacement heifers, and high milk prices on the one hand, a shortage of grazing land, and environmental destruction due to a decreasing number of unwanted cattle population on the other side.

Effects of beef semen and beef embryo strategies on profitability: Economics of using beef semen and beef in vitro–produced embryo transfer in Jersey herds

Dairy herds have adopted sexed semen (SS) and beef semen (BS) to control heifer inventory and increase calf sales revenue. Beef in vitro-produced embryo transfer (beef IVP-ET) may be an alternative to increase calf sales revenue. Additionally, raising those Jersey-beef crossbred or pure beef animals in a dairy system may be a new source of revenue. We aimed to evaluate the effects of breed strategies combining dairy conventional semen (CS), SS, BS, and beef IVP-ET on herd dynamics and profitability with strategies of marketing those animals at 1 d old or raising them to a weight of 180 kg. A Markov chain model was developed to maximize the profitability of Jersey herds by changing the number of dairy heifers sold at birth and the culling rate of cows in their third parity or greater. The model presents inputs on the reproductive and productive performance of heifers and cows over time. The last year's data (year 10, steady state) was used to calculate accrual operational cost and revenue per cow per year. We varied the breeding strategy by breeding order and parities, the embryo transfer cost ($85 or $170), the pure beef calf market price ($200 or $300), and the marketing strategy. A total of 8 scenarios plus a default scenario were simulated. Overall, the proportion of SS use was 47.3 ± 0.6% (mean ± SD). For the scenarios replacing all CS breedings with BS breedings, the percentage of BS used was 52.3 ± 0.6%. When beef IVP-ET was used, the percentages of BS and beef IVP-ET used were 22.4 ± 0.1% and 31.0 ± 0.1%, respectively. We observed that when we compared the combination of BS and dairy SS with the default scenario, the production of purebred Jersey male calves was reduced by 83.5%, and profit per cow per year was increased from $113.50 to $203.30. When a beef IVP-ET cost of $85 per transfer was used (scenarios 2 and 3), profit per cow per year was $145.50 and $176.20 for pure beef calf prices of $200 and $300, respectively. In scenario 4, with a beef IVP-ET cost of $170, the lowest profit ($52.90 per cow per year) was found when marketing 1-d-old pure beef calves at $200. The highest profit was achieved for the scenario of raising the Jersey-beef crossbred animals to 180 kg ($232.90, scenario 6), followed by scenario 7 ($222.90, using the combination of BS, dairy SS, and beef IVP-ET) with an embryo transfer cost of $85. Under the current market conditions, combining SS and BS in the reproductive program was a feasible economic opportunity for Jersey herds, yielding the highest net return. The adoption of beef IVP-ET in a reproductive program can potentially increase profit per cow per year, but its profitability will depend on the beef IVP-ET pregnancy cost, the pure beef market price, calf performance, and herd reproductive performance. In conclusion, raising the Jersey-beef crossbred calves may be a profitable strategy, and dairy producers need to evaluate the best option to invest in, as it will take extra risk to produce high-quality animals.

Comparative study of reproductive and estrus characteristics of sexed and conventional semen in crossbred cows under field conditions.

Sexed semen (SS), a reproductive biotechnology tool, can alter the sex ratio of offspring in bovines. This study elucidates a comparative analysis of estrus-related parameters influencing conception rate and pregnancy losses under field conditions between conventional and SS. In the present study, artificial insemination with (SS; n = 143) and conventional semen (CS; n = 143) was performed at spontaneous estrus, i.e., 16-18 h after the onset of estrus signs, to analyze their comparative evaluation in terms of conception rates in crossbred cows under field conditions. Different parameters such as age, parity, body condition score (BCS), estrus duration, inter-estrus interval (IEI), diameter of pre-ovulatory follicle (DPOF) at estrus, and cervical mucus properties (pH and spinnbarkeit [SBK]) were recorded for each cow. The first insemination conception rates for sexed and conventional semen were 55.24% and 63.63% whereas the overall conception rates were 49.14% and 57.37% on days 35 and 75 post-insemination, respectively, with no significant difference (p > 0.05). Conception rates between sexed and CS inseminations were statistically significant (p < 0.01), whereas factors such as age, parity, BCS, DPOF, IEI), and SBK value exhibited no substantial variance (p > 0.05) for both types of semen straw. SS straws yielded a conception rate equivalent to CS straws, with estrus duration being the key factor affecting conception under field conditions.

Semen sexing and its impact on fertility and genetic gain in cattle.

Semen sexing is among one of the most remarkable inventions of the past few decades in the field of reproductive biotechnology. The urge to produce offspring of a desired sex has remained since traditional times. Researchers have tried many methods for accurate semen sexing, but only the flow cytometry method has proved to be effective for commercial utilization. However, there were always concerns about the effects of sexed semen, especially on fertility and the rate of genetic gain. Some concerns were genuine because of factors such as low semen dosage in sexed semen straws and damage to sperm during the sorting process. Various researchers have conducted numerous studies to find out the effect of sexed semen on fertility and, in this article, we reflect on their findings. Initially, there were comparatively much lower conception rates (∼70% of conventional semen) but, with refinement in technology, this gap is bridging and the use of sexed semen will increase over time. Concerning genetic gain with use of sexed semen, a positive effect on rate of genetic progress with the use of sexed semen has been observed based on various simulation studies, although there has been a mild increase in inbreeding.

40 years of AETE: the contribution of scientists and practitioners to the progress of reproductive biotechnologies in Europe.

This conference celebrates the 40th anniversary of AETE. Over the past 40 years, AETE has served as a forum for scientists, practitioners, and students working in assisted animal reproduction in livestock species. AETE conferences have reflected developments in the field, from basic to applied science, as well as regulatory changes in assisted animal reproduction practices. Europe has led the way in these developments for many years, progressing from artificial insemination, embryo transfer, and cryopreservation to semen sexing, in vitro production of embryos, cloning by nuclear transfer, genomic selection, and the rescue of highly endangered species. These significant contributions were made possible by the support of funding agencies, both at the national and European levels, promoting cooperation between scientists and practitioners. Assisted reproduction, and animal breeding more generally, face opposition from various groups, including animal rights activists, vegetarians, proponents of organic farming, environmentalists, certain political parties, and increasing regulatory burdens. These challenges seriously affect funding for scientific research, the work of practitioners, and the breeding industry as a whole. It is crucial to invest time and resources in communication to remind the public, politicians, and regulators of the achievements in this field and the contributions made to the food supply chain and the care of the rural and natural environment.

Analysis of Motility Characteristic of Pesisir Bulls Sexed Semen with Different Pre-Freezing Method Based on Computer Assisted Sperm Analyzer (CASA)

This study aimed to find the best combination between pre-freezing method and layer of post sexing on semen quality of Pesisir Bulls. This study used 2 Pesisir Bulls. The semen was evaluated using Computer Assisted Sperm Analyzer (CASA). This study used factorial randomized block design with 2 factors. Factor A was sexed semen layer of BSA column with 2 level, whereas Factor B was pre-freezing method with 3 level. Analysis of Variance (ANOVA) were used in this study for data Analysis. According to the analysis of variance, there is no interaction of the combination of two factors on each paramters. Pre-freezing method showed highly statistically significant effect (P&lt;0.01) on the quality of motility on upper layer and bottom layer which was about (52.86-72.93%; 52.32-65.50%) and about (40.17-56.99%; 40.33-53.18%) on progressive motility. The value of Distance Curve Line on (39.15-43.24 μm; 49.25-53.86 μm), Distance Average Path (22.38-24.60 μm; 26.52-29.94 μm), Distance Straight Line (17.32-19.07 μm; 20.93-24.25 μm). The value of Velocity Curve Line (88.67- 97.50 μm/s; 109.85-117.90 μm/s), Velocity Average Path (50.98- 55.63 μm/s; 59.32- 64.69μm/s), Velocity Straight Line (34.45-42.37 μm/s; 46.80-50.62 μm/s), Beat Cross Frequancy (23.91-25.17 Hz; 25.63-27.35 Hz), Straightness (0.75-0.77; 0.77-0.80), and Wobble (0.56-0.57; 0.53-0.55), highly statistically significant (P&lt;0.01) on post sexing layers. Meanwhile, the value of Amplitude of Lateral Head (4.24-4.94 μm; 4.25-4.44 μm) showed highly significant effect (P&lt;0.01) on factor A and factor B treatment, and value Linearity was about (0.42-0.44; 0.43-0.44) showed not significant effect (P&gt;0,05) on every factor. According to the study, it can be concluded that the best treatment was treatment modified procedure layer by space the straw 16 cm every layers and The quality of post sexing X- and Y- spermatozoa motility effect on motility characteristic such as DCL, DAP, DSL, VCL, VAP, VSL, STR, WOB, ALH and BCF.

Genetic group and swim-up processing affect SYBR Green real-time PCR-based porcine semen sex ratio in Landrace and its crossbred boars.

Determination of factors affecting sex ratio is important while considering application of sex ratio enrichment approach. Present study aimed to design a SYBR Green qPCR-based method for measurement of primary sex ratio and to evaluate different factors (genetic group, sire, spermiogenic cycle and processing layer) affecting boar sperm sex ratio. The qPCR was based on relative copy number analysis of sex chromosome-specific single copy gene fragments with an autosomal gene as reference and was evaluated using DNA dilution series from pigs with numerically normal karyotype. The sex ratio was estimated from genomic DNA samples isolated from boar semen collected from different genetic groups at different time points and different processing layers. The X chromosome frequencies of semen samples revealed significant effect of genetic group. However, significant variation was observed neither within same genetic group nor between ejaculates of different spermatogenic cycles. Among the processing techniques studied, swim-up technique produced a significant X sperm enrichment in comparison to control whereas, Percoll density gradient failed to show any significant difference among layers. The lower layer in swim-up technique was found to contain higher proportion of X sperms. The designed qPCR is found to be an easy, less time-consuming method and does not require high end laboratory facilities or the specialized expertise. The lower layer of swim-up processing has a scope for X sperm enrichment in boar semen with proper validation.

X-Y Chromosom bearing Sperm Proportion of Local Ram after Sexing with Different Combination of Bovine Serum Albumin (BSA) Concentration

The research aims to evaluate proportion of X-Y chromosom bearing sperm after sexing of local ram semen with different combination of BSA concentration. The research object was ten ejaculated semen of local ram, three years old. The research design used CRD (completely randomize design) with four treatments of BSA concentration combination on upper and bottom layer (T1: 3% &amp; 6%, T2: 4% &amp; 6%, T3: 5% &amp; 10%, and T4: 6% &amp; 12%), and 10 repetitions. Data analysis using analysis variance and Duncan’s Multiple Range Test. The result showed that combination of BSA concentration was significantly effect on proportion of X-Y chromosome bearing sperm of local ram sperm. The higher average proportion of X- and Y- chromosome bearing sperm was obtained at combination 5% (75.55±1.09% for X) at upper layer and 10% BSA (76.45±1.12% for Y) of bottom layer. The conclusion is that combination of BSA concentration significantly effect on proportion of X-Y chromosome bearing sperm, and concentration of 5% and 10% BSA at upper layer and bottom layer gave the higher proportion of X-Y chromosome bearing sperm of local ram sperm.

Using mid-infrared spectroscopy to identify more fertile cows for insemination to sexed semen

Context Broader applications of milk mid-infrared spectral data could add value to milk-recording data. One such application is to rank cows on the probability of conception to first service (MFERT) which could help prioritise cows for insemination with dairy sexed semen (SS). Aims This study compared the use of MFERT estimates against two other approaches, to (1) identify most and least fertile dairy cows and (2) prioritise cows predicted to be most fertile for first service insemination with SS. Methods Mid-infrared spectral data from first herd test after calving was used to generate 13 379 MFERT predictions for 76 cohorts. Reproduction records were used to calculate reproductive parameters, calf numbers and net benefit, i.e. calf values minus mating costs, for two breeding programs. Breeding program 1 used SS and conventional dairy semen, while Breeding program 2 used SS, conventional dairy and beef semen. Three semen-allocation approaches were compared, namely, allocation via MFERT, calving date (CDATE) or assignment via random number generator (RANDOM). Key results MFERT significantly outperformed (1) RANDOM in identifying cows most and least likely to calf after first insemination (P &lt; 0.05), and (2) both CDATE and RANDOM in identifying cows most and least likely to calf overall (P &lt; 0.05). This resulted in up to 1.5 and 4.5 more dairy heifer calves, in Breeding programs 1 and 2 respectively, and up to six fewer dairy-beef calves in Breeding program 2. Differences in net benefit among semen-allocation approaches were modest, although generally favoured MFERT. Few significant differences between MFERT and CDATE were found. However, significant net benefit differences among all three semen-allocation approaches were seen in Breeding program 2. Conclusions MFERT outperformed CDATE and RANDOM in identifying most and least fertile cows. Realised net benefits of semen allocation by MFERT over other approaches were modest. Given the impact of semen type and dairy-beef calf prices value proposition will vary. Implications Our study confirmed that MFERT can add value to milk recording data by identifying the most and least fertile cows. As MFERT value is sensitive to individual farm parameters, incorporation alongside other fertility parameters into a decision support tool is desirable.

Качественные характеристики замороженно-оттаянного семени (обычное и разделенное по полу ) у быков-производителей голштинской черно-пестрой породы и возраст полового созревания полученных от них телочек

A study was carried out to assess the quality of frozen-thawed semen using the sex separation method and the traditional method in a comparative aspect, and the authors believe that the work will be of some interest to specialists in zootechnical and biological fields, as well as to veterinary specialists. The work was carried out at the Federal Research Center for Animal Husbandry named after Academy Member L.K. Ernst and on the basis of LLC “Agrofirma Zarya”, Bogorodsky district, Nizhny Novgorod region in the period from 2017 to 2022. usng the semen of eight sires. To assess the quality of the semen, the index of nuclear DNA fragmentation (nDNA) in chromatin was determined, and the activity of spermatozoa was assessed visually and using the Biola AFS‑500 sperm analyser (ZAO Biola, Moscow). On the basis of the studies conducted, it was found that the morphology of the spermatozoa depends on the individual characteristics of the sires; the content of abnormal spermatozoa varies from 2 to 8% when collected by the traditional method and from 4.10 to 15% when collected by the sexing method. A significant difference between the sires is observed in the iDNA fragmentation index – this indicator varies from 2.66 to 8.62% and from 8.50 to 28.57%, respectively. The division of spermatozoa by sex has a direct effect on the quality indicators, leading to a decrease in their activity. This indicator is 11.2% higher in semen obtained by the traditional method than by the alternative technique. The number of abnormal cells in the semen divided by sex is 2.2% higher than in the semen collected by the traditional method, and the proportion of spermatozoa with fragmented iDNA is 7% higher. The velocity of spermatozoa in the studied doses of semen collected using the technique of sex separation was 96–113 μm/s immediately after thawing, and five hours after incubation at +38°C in a thermostat this indicator decreased to the level of 20–34 μm/s. The age of puberty of their calves obtained from the sexed semen from birth to fruitful insemination is 490 days, which is 16 days more than in group I, where heifers were obtained from the semen frozen in the traditional way (TS). The term of fruiting in heifers born from the use of the sexed semen (SS) was 273 days, while that of heifers born from the use of traditionally frozen semen (TS) was 275 days (2 days more). The age of heifers from birth to first calving in the SS group was 762 days and was 14.4 days more than in the TS group, which was 748 days.

Идентификация популяций клеток крови рыб на основе сверточной нейронной сети для составления лейкограммы

A study was carried out to assess the quality of frozen-thawed semen using the sex separation method and the traditional method in a comparative aspect, and the authors believe that the work will be of some interest to specialists in zootechnical and biological fields, as well as to veterinary specialists. The work was carried out at the Federal Research Center for Animal Husbandry named after Academy Member L.K. Ernst and on the basis of LLC “Agrofirma Zarya”, Bogorodsky district, Nizhny Novgorod region in the period from 2017 to 2022. usng the semen of eight sires. To assess the quality of the semen, the index of nuclear DNA fragmentation (nDNA) in chromatin was determined, and the activity of spermatozoa was assessed visually and using the Biola AFS‑500 sperm analyser (ZAO Biola, Moscow). On the basis of the studies conducted, it was found that the morphology of the spermatozoa depends on the individual characteristics of the sires; the content of abnormal spermatozoa varies from 2 to 8% when collected by the traditional method and from 4.10 to 15% when collected by the sexing method. A significant difference between the sires is observed in the iDNA fragmentation index – this indicator varies from 2.66 to 8.62% and from 8.50 to 28.57%, respectively. The division of spermatozoa by sex has a direct effect on the quality indicators, leading to a decrease in their activity. This indicator is 11.2% higher in semen obtained by the traditional method than by the alternative technique. The number of abnormal cells in the semen divided by sex is 2.2% higher than in the semen collected by the traditional method, and the proportion of spermatozoa with fragmented iDNA is 7% higher. The velocity of spermatozoa in the studied doses of semen collected using the technique of sex separation was 96–113 μm/s immediately after thawing, and five hours after incubation at +38°C in a thermostat this indicator decreased to the level of 20–34 μm/s. The age of puberty of their calves obtained from the sexed semen from birth to fruitful insemination is 490 days, which is 16 days more than in group I, where heifers were obtained from the semen frozen in the traditional way (TS). The term of fruiting in heifers born from the use of the sexed semen (SS) was 273 days, while that of heifers born from the use of traditionally frozen semen (TS) was 275 days (2 days more). The age of heifers from birth to first calving in the SS group was 762 days and was 14.4 days more than in the TS group, which was 748 days.

Semen Sexing: Technique, Scope, and Constraints

Semen Sexing: Technique, Scope, and Constraints

PSI-1 An Evaluation of Functionality of Cryopreserved Sperm Cells Treated with Heifer-Plus™

Abstract The commercial beef cattle industry produces calves for replacement or slaughter. Female replacements are important to advance herd genetics, therefore, a tool to influence sex ratios may enhance reproductive efficiency. A commercial semen sexing kit, Heifer-Plus™, used in conjunction with artificial insemination, may alter the sex ratio of offspring by increasing motility of the X chromosome-bearing sperm. The aim of this research was to assess the methodology of Heifer-Plus™ through evaluation of motion patterns and kinematic parameters in conventional semen straws. Four bulls representing Angus, Wagyu, and Holstein breeds were utilized. Six straws of cryopreserved semen from each bull were thawed in a water bath (37.5°C for 35 sec). Three straws from each bull were pooled and treated with Heifer-Plus™ and 3 straws were pooled as the no-treatment control. Post treatment, all samples were aliquoted in microcentrifuge tubes and Computer Assisted Semen Analysis (CASA) measurements of motility and kinematic factors were assessed. Semen samples were held at 37.5°C for incubation for three 15-min periods (15-mins, 30-mins, and 45-mins) measuring thermoresistance and longevity of spermatozoa. After incubation, 80 µL of each semen sample were observed on CASA. Data were analyzed using ANOVA method in GraphPad Prism and P-values ≤ 0.05 were considered significant. No effect of treatment on motility parameters or rapid velocity were measured, however there was a decrease in total motility (P=0.0045), progressive motility (P=0.0115) and rapid velocity (P =0.0099) across time intervals. Heifer-Plus™ treated cells had higher incidence of static velocity compared to control (P = .0038). Semen samples were clustered into subpopulation threshold-based on sperm average path velocity (VAP) and linearity (LIN) at each time point. Spermatozoa treated with Heifer-Plus™ consistently exhibited a high velocity and variable linearity therefore were categorized consistently into two categories at each time point.

Study of the quality and integrity of spermatozoa acrosome caps in frozen sexing semen Friesian Holstein cattle

Artificial insemination (AI) of dairy cows using sexing semen is the right choice to obtain female calves as replacement stock. The success of AI is influenced by the quality of the spermatozoa used. The purpose of this study was to determine the quality of semen produced by Lembang Artificial Insemination Center. The material used is 30 frozen semen straws of FH cattle produced by Lembang Artificial Insemination Center. This research method uses observational methods. The research variables included individual motility, viability, abnormalities, concentration, total motile spermatozoa, and intact acrosome caps of spermatozoa. The data obtained were analyzed by the Analysis of Variance (ANOVA) test and continued with Duncan's test if significantly different. The results showed that individual motility, concentration, total motile spermatozoa, and intact acrosome caps of spermatozoa had a very significant effect on all treatments (P&lt;0.01), while spermatozoa abnormalities had a significant effect (P&lt;0.05) on all treatments, but on viability, there was no effect (P&gt; 0.05) in all treatments. Motility of individual spermatozoa in non-sexing semen (55.80±4.56)%, sperm X (46.30±5.36)%, sperm Y (46.70±6.40)%. Viability of spermatozoa in non-sexing semen (74.57±4.05)%, sperm X (73.24±2.30)%, sperm Y (72.51±2.68)%. Spermatozoa abnormalities in non-sexing semen (2.73±2.24)%, sperm X (4.94±1.57)%, sperm Y (3.25±2.72)%. Concentration of non-sexing semen (33.88±1.98 million/mini straw), sperm X (25.06±4.29 million/mini straw), sperm Y (25.13±5.74 million/mini straw). The number of sperm motile non-sexing (18.60±1.58 million/mini straw), sperm X (11.68±2.82 million/mini straw), sperm Y (25, 11.64±2.68 million/mini straw). Intact acrosome caps, non-sexing semen (78.40±4.84)%, sperm X (74.08±3.80)%, sperm Y (70.70±4.78)%.

Addressing stray animal population through alteration of sex ratio

Livestock plays a significant role in rural economy and livelihood by providing milk, meat, hide, drought power, etc. India’s livestock sector is one of the largest in the world with a holding of 11.6% of world livestock population. But due to economic reasons, dairy farmers have a strong preference for female calves for milk production and hence there is a very limited demand for male calves. Apart from that, there are several other reasons such as negligence of the indigenous populations and excessive focus on crossbreeding in the past few decades, increased mechanisation and the national policy to ban on cow slaughter have further added to the problem. In the common parlance, stray cattle include low-yield cows, bulls or calves that are abandoned and free to roam about in the open during the daytime because they are unproductive and creating traffic nuisance in cities, they also attack crops in villages. Therefore, techniques for gender selection and skewing of sex ratio towards female are demand of the hour. Flow cytometric sorting of spermatozoa is one of the best approaches to select the sexed semen for desire sex of calf, but its cost and patented technology is a definite disadvantage of this technology. In the present review, we will discuss in detail about the techniques available for skewing of sex ratio to address the stay animal population.

Characteristics of Bali Bull (Bos Sondaicus) Sexed Sperms with Freeze Dry Egg White at Different Incubation Time

The development of reproductive technology for the separation of spermatozoa with X and Y chromosomes, which is better known as sexing, can be carried out in vitro using various methods, one of which is using freeze dry egg whites. This study aims to determine the quality of semen based on incubation time. This study used four types of treatment, namely P0 = No Incubation, P1 = Incubation 30 minutes, P2 = Incubation 45 minutes, P3 = Incubation 60 minutes with six replications. Parameters observed were the quality of spermatozoa macroscopically (volume, odor, color and consistency) and microscopically (motility, abnormality, concentration, intact plasma membrane, intact acrosome cap). Y using descriptive statistical test. The results of analysis of variance that sexing spermatozoa using freeze dry egg whites at different incubation times showed a significant effect (P&lt;0.05) on intact plasma membrane (IPM), intact acrosomal membrane (IAM), but had no significant effect P&gt;0.05) on concentration, motility, and abnormalities. Evaluation of fresh Bali cattle spermatozoa showed results that were in accordance with the standards for further examination of semen sexing. Incubation time of 30 minutes in the sexing process of spermatozoa caused a significant decrease in motility and concentration, meanwhile, IPM and IAM of sexed spermatozoa experienced a significant decrease in incubation time of 60 minutes, but the decrease was still within the normal range for spermatozoa. to be used in the artificial insemination process. Keywords: Sexing, incubation, concentration, motility, abnormality, intact plasma membrane, intact acrosome caps.

Effect on physiological parameters and semen quality upon oral administration of fresh onion juice to V-line rabbit buck during severe heat stress

Severe heat stress is recognized as a factor that severely influences the semen quality and antioxidant status of rabbits. In this context, fresh onion juice (FOJ) may be a safe and useful option to improve reproductive performance. This research was designed to evaluate the anti-stress effects of FOJ on physiological and semen parameters in heat-stressed bucks. Thirty-six V-line rabbit bucks were randomly distributed into three groups. The bucks received FOJ orally at different doses [0 (water), 1.5, and 3 ml/kg live body weight] every 2 days over a period of 2 months, with 3 weeks as an adaptation period. FOJ treatments significantly improved semen characteristics, such as libido, mass and individual sperm motility, semen concentration, sperm viability, and acrosome reaction with increased initial seminal fructose, via the oral administration of 1.5 and 3 mL FOJ/kg body weight, compared with the findings in control bucks. Seminal plasma antioxidant status was significantly enhanced by FOJ treatments. It was concluded that the oral administration of FOJ under severe heat stress can improve bucks’ semen characteristics and sex hormone concentrations except for testosterone, and it is considered a good strategy for improving the heat resistance of rabbit bucks, possibly due to its antioxidant activity.

Pregnancy and calving rates improved using modified swim-up method for buffalo semen sexing.

Present study aimed to evaluate field fertility rate and calf sex ratio of Nili Ravi buffalo semen sexed through modified swim-up method (Animal Reproduction Science, 182, 2017, 69). For this purpose, five mature Nili-Ravi buffalo bulls kept at semen production unit, Qadirabad, Pakistan, were selected. Two consecutive ejaculates per week were collected with artificial vaginą for 3weeks. Qualified semen ejaculates were pooled and divided into two aliquots. The first aliquot was processed by routine procedure (control), whereas the second was processed by modified swim-up technique. After separation, semen was diluted in tris-citric acid extender and cryopreserved using standard techniques. Sexed semen was evaluated for fertility trials during peak breeding season. Artificially inseminated animals were examined for pregnancy rate through rectal palpation at least 3months after insemination under field conditions. Calving ratio of female and male calves were recoded after Parturition. The fertility rate was higher (p<.05) in X-sorted sperm (70%) as compared with control (47%). The female calf ratio was higher (p<.05) in X-sorted sperm (78.58%) compared with control (53.3%). In Conclusion, conception rate and production of female calf were significantly higher with sexed semen separated through modified swim-up method compared with unsexed control.

Molecular sexing in Bos taurus using quantitative polymerase chain reaction (qPCR) method

Cattle are animals that are widely found all over the world which is the domestication of bulls. In Indonesia, domesticated cattle are used as livestock, could be meat cattle or dairy cattle. The sex of the cattle is very influential in terms of selling, especially the type of bull. Calf bull is a product of the process of artificial insemination with spermatozoa resulting in sexing. Mammals have X and Y chromosomes to distinguish their sex. Each chromosome has a special gene such as the SRY gene on the Y chromosome and the PLP gene on the X chromosome. Molecular methods are effective methods of determining the chromosomes carried by spermatozoa. Both special genes are found in the home box (GADPH) of mammals. Primer is made from the mRNA SRY (sex-determining region Y) sequence from Bos taurus with a size above 200bp (SRY B) and below 200bp (SRY A) so that optimal results are obtained between the two. The type of sample that has been used in this research was sexing semen from limousin bulls that are treated from 4 pairs of primers each. The results of the qPCR from both primers are viewed from the melt-peak graph and comparison analysis. The differences between SRY A and SRY-B primer indicates that SRY-A produces a more stable melt-peak graph than SRY B. This indicates that the SRY A primer is more stable when used for molecular verification processes using qPCR.