{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:22:41Z","timestamp":1785410561280,"version":"3.56.0"},"reference-count":27,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,4,19]],"date-time":"2026-04-19T00:00:00Z","timestamp":1776556800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Agris Sardegna"},{"DOI":"10.13039\/501100005642","name":"University of Sassari","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005642","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/01bnjbv91","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Cryptorchidism is the most common non-lethal congenital defect of the male reproductive system in sheep, with potential economic consequences for flock management. This study investigated the incidence, testicular morphology, ultrasonographic characteristics, semen quality, and sexual behavior of bilateral cryptorchid Sarda rams. Slaughterhouse inspections of 2360 lambs showed an incidence of 0.87% cryptorchidism. Cryptorchid testes were significantly rounder and lighter than intact testes, indicating impaired development in affected animals. Ultrasonography of 15 adult bilateral cryptorchid rams showed that retained testes were markedly undersized and that the left testis was less frequently visualized. No significant association with age was detected within the studied age range. All ejaculates recovered from bilateral cryptorchid rams were azoospermic. Nevertheless, behavioral trials suggested that bilateral cryptorchid males retained sexual interest and the ability to identify estrous ewes. These findings confirm the infertility of bilateral cryptorchid Sarda rams while highlighting their preserved sexual behavior, suggesting a potential zootechnical use as teaser rams for heat detection. Repurposing cryptorchid males in this way could represent a potential alternative to surgically modified teaser rams or the use of aprons on intact rams.<\/jats:p>","DOI":"10.3390\/ani16081253","type":"journal-article","created":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T07:15:08Z","timestamp":1776669308000},"page":"1253","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Cryptorchidism in Sarda Sheep: Incidence, Morphology, Ultrasonography and Behavioral Insights"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-9204-7848","authenticated-orcid":false,"given":"Charbel","family":"Nassif","sequence":"first","affiliation":[{"name":"Department of Agriculture, University of Sassari, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4186-2400","authenticated-orcid":false,"given":"Laura","family":"Mara","sequence":"additional","affiliation":[{"name":"Department of Animal Science, Agricultural Research Agency of Sardinia, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabrizio","family":"Chessa","sequence":"additional","affiliation":[{"name":"Department of Animal Science, Agricultural Research Agency of Sardinia, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5049-5713","authenticated-orcid":false,"given":"Ignazio","family":"Cossu","sequence":"additional","affiliation":[{"name":"Department of Animal Science, Agricultural Research Agency of Sardinia, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marilia","family":"Gallus","sequence":"additional","affiliation":[{"name":"Department of Animal Science, Agricultural Research Agency of Sardinia, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federico","family":"Melis","sequence":"additional","affiliation":[{"name":"Department of Animal Science, Agricultural Research Agency of Sardinia, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6297-1556","authenticated-orcid":false,"given":"Antonello","family":"Cannas","sequence":"additional","affiliation":[{"name":"Department of Agriculture, University of Sassari, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1940-1398","authenticated-orcid":false,"given":"Maria","family":"Dattena","sequence":"additional","affiliation":[{"name":"Department of Animal Science, Agricultural Research Agency of Sardinia, 07100 Sassari, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1016\/S0749-0720(15)30681-2","article-title":"Congenital Defects of Sheep","volume":"9","author":"Dennis","year":"1993","journal-title":"Vet. 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