Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Mar-Apr;36(2):731-737.
doi: 10.21873/invivo.12759.

Sperm Characteristics in Microminipigs

Tatsuo Kawarasaki  1 , Satoko Enya  2 , Masayoshi Otake  2
Affiliations

Sperm Characteristics in Microminipigs

Tatsuo Kawarasaki et al. In Vivo. 2022 Mar-Apr.

Abstract

Background/aim: The microminipig is a relatively new type of mini pig; microminipigs weigh about 10 kg at 6 months of age and are expected to be of use in drug discovery research and safety tests. Herein, we analyzed the characteristics of ejaculated sperm from microminipigs.

Materials and methods: Sperm parameters such as microstructure and sensitivity to cold shock were investigated using optical or scanning electron microscopy.

Results: Ejaculate volumes and total numbers of sperm were lower than in standard pig strains, but were proportional to body weight. Ejaculation time, pH of the ejaculate, sperm motility and morphology, and sensitivity to cold shock were similar to those of standard pig strains.

Conclusion: Herein, we provide the first characterization of the ejaculates of microminipigs and demonstrate that this type of pig will be useful not only in medical research, but also in investigations into sperm preservation in different pig breeds.

Keywords: Pig; SEM; characteristic; cold shock; microminipig; morphology; sperm.

PubMed Disclaimer

Conflict of interest statement

The Authors declare that no conflicts of interest exist.

Figures

Figure 1
Figure 1. Measurement positions in spermatozoa. The positions where the spermatozoa were measured are indicated by green or orange lines. Ten spermatozoa from each of six microminipigs, five Landrace pigs and five Duroc pigs were analyzed by SEM. Whole length (A①), head length (B②), head width (width1, widest part B③; width2, post acrosomal region B④), head thickness (thickness1, peri-acrosomal part C⑤; thickness 2, post-acrosomal region C⑥), neck length (B⑦), midpiece length(D⑧), midpiece width(E⑨), principal piece width (width1, near start point E⑩; width 2, near end point F⑪), end piece length(F⑫), and end piece widths (width1, narrow part F⑬; width2, thick part F⑭) were measured.
Figure 2
Figure 2. Proportion of motile spermatozoa after cold shock treatment. Sperm motility rates were higher with increased culture time (p=0.0001) and with decreased dilutions (p=0.0003). Results are represented as mean±SE.
Figure 3
Figure 3. Proportions of sperm with normal acrosomes rate after cold shock treatment. The rates of sperm with normal acrosomes increased with culture time (p<0.0001). In the 5-h culture group, the rate of spermatozoa with normal acrosomes decreased with increasing dilution (p<0.0307). Results are represented as mean±SE.
See this image and copyright information in PMC

References

    1. Kaneko N, Itoh K, Sugiyama A, Izumi Y. Microminipig, a non-rodent experimental animal optimized for life science research: preface. J Pharmacol Sci. 2011;115(2):112–114. doi: 10.1254/jphs.10r16fm. - DOI - PubMed
    1. Kawaguchi H, Yamada T, Miura N, Takahashi Y, Yoshikawa T, Izumi H, Kawarasaki T, Miyoshi N, Tanimoto A. Reference values of hematological and biochemical parameters for the world smallest microminipigs. J Vet Med Sci. 2012;74(7):933–936. doi: 10.1292/jvms.11-0571. - DOI - PubMed
    1. Miura N, Kucho K, Noguchi M, Miyoshi N, Uchiumi T, Kawaguchi H, Tanimoto A. Comparison of the genomic sequence of the microminipig, a novel breed of swine, with the genomic database for conventional pig. In Vivo. 2014;28(6):1107–1111. - PubMed
    1. Ando A, Imaeda N, Ohshima S, Miyamoto A, Kaneko N, Takasu M, Shiina T, Kulski JK, Inoko H, Kitagawa H. Characterization of swine leukocyte antigen alleles and haplotypes on a novel miniature pig line, Microminipig. Anim Genet. 2014;45(6):791–798. doi: 10.1111/age.12199. - DOI - PubMed
    1. Enya S, Kawarasaki T, Otake M, Kangawa A, Uenishi H, Mikawa S, Nishimura T, Kuwahawa Y, Shibata M. Preservation and reproduction of microminipigs by cloning technology. In Vivo. 2016;30(5):617–622. - PubMed

LinkOut - more resources