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The efficiency of artificial insemination (AI) in pig breeding plays a critical role in improving reproductive performance, reducing breeding costs, and increasing the sustainability of the pig farming industry. Unlike cervical insemination (CAI), PCAI allows for more precise sperm deposition in the uterus, improving the chances of conception and this ensures more effective intensive boar management.

To evaluate the effectiveness of PCAI in improving pig breeding efficiency, a meta-analysis was conducted using Jamovi software and algorithms from the metaphor package (R). Publication bias estimation was integrated into the analysis to ensure the reliability of the findings. The meta-analysis compared PCAI and CAI across three critical reproductive parameters: farrowing rate, fecundity index, and litter size. Criteria for study inclusion were defined to ensure the integrity of the analysis:  the exclusion of studies involving exogenous hormonal treatments that could interfere with natural reproductive processes, the inclusion of studies with at least 20 animals per group, availability of group sizes and insemination doses, and provision of relevant variation statistics.

A total of 34 studies were included in the analysis for the farrowing rate, 33 studies for the fecundity index, and 33 studies for the litter size. The inclusion of such a large number of studies enhanced the robustness of the meta-analysis and allowed for a comprehensive evaluation of PCAI’s impact on pig breeding efficiency.

The meta-analysis results showed that PCAI does not significantly worsen the farrowing rate. Specifically, the average log odds ratio based on the random-effects model was 0.0061 (95% CI: -0.2042 to 0.2163), indicating no detrimental effect on the farrowing rate when PCAI was used. Similarly, no significant differences were found between PCAI and CAI for the fecundity index (average standardized mean difference was 0.1156; 95% CI: -0.0790 to 0.3103), nor for litter size (average standardized mean difference was 0.0226; 95% CI: -0.0670 to 0.1123). These findings suggest that PCAI is comparable to traditional AI methods in terms of key reproductive parameters, which is a crucial consideration for breeders seeking to improve their production efficiency.

The publication showed that use of PCAI can offer several economic benefits. By increasing the efficiency of boars and making desirable genetics more accessible, PCAI reduces the need for maintaining a large number of boars on farms. This not only reduces the costs associated with keeping boars, but also promotes the wider use of high-quality genetic material, leading to the genetic improvement of industrial pigs.

 

References

Apić, J., Vakanjac, S., Stančić, I., Radović, I., Jotanović, S., Kanački, Z., Stanković, B. (2015). Sow fertility after insemination with varying doses of volume and spermatozoa count. Turkish Journal of Veterinary and Animal Sciences, 39(6), 709–713. https://doi.org/10.3906/vet-1503-50.

Bortolozzo, F., Menegat, M., Mellagi, A., Bernardi, M., & Wentz, I. (2015). New Artificial Insemination Technologies for Swine. Reproduction in Domestic Animals, 50(S2), 80–84. https://doi.org/10.1111/rda.12544

Cane, F., Pereyra, N., Cane, V., Patricia, M., Teijeiro, J. M. (2019). Improved farrowing rate using intrauterine insemination in sows. Revista Mexicana De Ciencias Pecuarias, 10(3), 583–594. https://doi.org/10.22319/rmcp.v10i3.4772.

Dimitrov, S., Zmudzki, J. (2009). Post-cervical insemination of sows with low sperm concentration dose in the commercial pig farm. Bulletin of the Veterinary Institute in Pulawy, 53(2), 225–228.

Feitsma H. (2009). Artificial insemination in pigs, research and developments in The Netherlands, a review. Acta Scientiae Veterinariae, 37 (1), 61-71. https://www.ufrgs.br/actavet/37-suple-1/suinos-07.pdf

Fitzgerald, R. F., Jones, G. F., Stalder, K. J. (2008). Effects of intrauterine and cervical artificial-insemination catheters on farrowing rate and litter size. Journal of Swine Health and Production, 16(1), 10–15.

Francis, G. (2013). Replication, statistical consistency, and publication bias. Journal of Mathematical Psychology. l, 57, 153-169.  https://www.sciencedirect.com/science/article/pii/S002224961300014X?via%3Dihub, https://doi.org/10.1016/j.jmp.2013.02.003

Hancock, J., & Hovell, G. (1961). The effect of semen volume and number of spermatozoa on the fertility of intra-uterine inseminations of pigs. Animal Production, 3(2), 153-161. Doi:10.1017/S0003356100033912.

Hernández-Caravaca, I., Izquierdo-Rico, M. J., Matás, C., Carvajal, J. A., Vieira, L., Abril, D., Soriano-úbeda, C., García-Vázquez, F. A. (2012). Reproductive performance and backflow study in cervical and post-cervical artificial insemination in sows. Animal Reproduction Science, 136(1), 14–22. https://doi.org/10.1016/j.anireprosci.2012.10.007.

Hernández-Caravaca, I., Llamas-López, P. J., Izquierdo-Rico, M. J., Soriano-Úbeda, C., Matás, C., Gardón, J. C., García-Vázquez, F. A. (2017). Optimization of post-cervical artificial insemination in gilts: Effect of cervical relaxation procedures and catheter type. Theriogenology, 90, 147–152. https://doi.org/10.1016/j.theriogenology.2016.11.027.

Knox R.V. (2016). Artificial insemination in pigs today. Theriogenology, 85(1), 83-93. https://doi.org/10.1016/j.theriogenology.2015.07.009.

Kovalenko, V., Pilipenko S. (2005). Intrauterine method of inseminating sows. Animal breeding of Russia, 11, 31.

Llamas-López, P. J., López-Úbeda, R., López, G., Antinoja, E., García-Vázquez, F. A. (2019). A new device for deep cervical artificial insemination in gilts reduces the number of sperm per dose without impairing final reproductive performance. Journal of Animal Science and Biotechnology, 10(1). https://doi.org/10.1186/s40104-019-0313-1.

Llanes Chalé, J. E., López, A.-A., Segura Correa, J. C., Álvarez Fleites, M. J., Góngora Castro, G. (2007). Gestation percentage and prolificacy of sows under tropical conditions using traditional and intra-uterine artificial insemination techniques. Livestock Research for Rural Development, 19(10), https://www.lrrd.org/lrrd19/10/llan19145.htm.

Mellado, M., Gaytán, L., Macías-Cruz, U., Avendaño, L., Meza-Herrera, C., Lozano, E. A., Rodríguez, Á. Mellado, J. (2018). Effect of climate and insemination technique on reproductive performance of gilts and sows in a subtropical zone of Mexico. Austral Journal of Veterinary Sciences, 50(1), 27–34. https://doi.org/10.4067/s0719-81322018000100106.

Pearodwong, P., Tretipskul, C., Panyathong, R., Sang-Gassanee, K., Collell, M., Muns, R., Tummaruk, P. (2020). Reproductive performance of weaned sows after single fixed-time artificial insemination under a tropical climate: Influences of season and insemination technique. Theriogenology, 142, 54–61. https://doi.org/10.1016/j.theriogenology.2019.09.032.

Pylypenko S.V. Physiological grounds and improvement of the pigs’ intrauterine insemination. Manuscript. Poltava, 2006, 32.

R Core Team (2021). R: A Language and environment for statistical computing. (Version 4.1) [Computer software]. Retrieved from https://cran.r-project.org. (R packages retrieved from MRAN snapshot 2022-01-01).

Roberts, P., Bilkei, G. (2005). Field Experiences on Post-cervical Artificial Insemination in the Sow. Reproduction in Domestic Animals, 40(5), 489–491. doi:10.1111/j.1439-0531.2005.00616.x.

Roca J., Vázquez J.M., Gil M.A., Cuello C., Parrilla I., Martínez E.A. (2006). Challenges in pig artificial insemination.  Reproduction in Domestic Animals, 41 (2), 43 – 53. DOI: 10.1111/j.1439-0531.2006.00664.x.

Sbardella, P. E., Ulguim, R. R., Fontana, D. L., Ferrari, C. V., Bernardi, M. L., Wentz, I., Bortolozzo, F. P. (2014). The post-cervical insemination does not impair the reproductive performance of primiparous sows. Reproduction in Domestic Animals, 49(1), 59–64. https://doi.org/10.1111/rda.12224.

Serret, C. G., Alvarenga, M. V. F., Cória, A. L. P., Dias, C. P., Corcini, C. D., Corrêa, M. N., Deschamps, J. C., Bianchi, I., Jr, T. L. (2005). Intrauterine artificial insemination of swine with different sperm concentrations, parities, and methods for prediction of ovulation. Anim Reprod, 2(4), 250-256.

Singh, M., Mollier, R. T., Sharma, P. H. R., Chaudhary, J. K. (2020). Reproductive performance in cervical and postcervical artificial insemination (PCAI) with liquid boar semen in Gunghroo × Hampshire crossbreed pig in Nagaland. Indian Journal of Animal Sciences, 90(5), 708–711. https://doi.org/10.56093/ijans.v90i5.104610.

Suárez-Usbeck, A., Mitjana, O., Tejedor, M. T., Bonastre, C., Moll, D., Coll, J., Ballester, C., Falceto, M. (2019). Post-cervical compared with cervical insemination in gilts: Reproductive variable assessments. Animal Reproduction Science, 211. https://doi.org/10.1016/j.anireprosci.2019.106207.

Ternus, E. M., Vanz, A. R., Lesskiu, P. E., Preis, G. M., Serafini, L., Consoni, W., Traverso, S. D., Cristani, J. (2017). Reproductive performance of gilts submitted to post-cervical artificial insemination. Arquivo Brasileiro de Medicina Veterinaria e Zootecnia, 69(4), 777–784. https://doi.org/10.1590/1678-4162-9285.

The Jamovi project (2022). Jamovi. (Version 2.3) [Computer Software]. Retrieved from https://www.jamovi.org.

Viechtbauer, W. (2010). Conducting meta-analyses in R with the metafor package. Journal of Statistical Software, 36, 1-48. https://www.jstatsoft. org/article/view/v036i03,  https://doi.org/10.18637/jss.v036.i03

Will, K. J., Mellagi, A. P. G., Bernardi, M. L., Bortolozzo, F. P., Ulguim, R. D. R. (2021). Perspectives of intrauterine artificial insemination applicability in gilts. Ciencia Rural, 51(5). https://doi.org/10.1590/0103-8478cr20200612.