{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T04:08:57Z","timestamp":1771042137325,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T00:00:00Z","timestamp":1676937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Increased knowledge of the developmental processes during gestation could provide valuable information on potential alterations in embryonic\/fetal development. We examined the development of ovine conceptus between the 20th and 70th day of gestation with three convergent analyses: (1) uterus ultrasound examination and measurement (eco) of crown\u2013rump length (CRL) and biparietal diameter (BPD) of the conceptus; (2) direct measurement (vivo) of CRL and BPD of the conceptus outside the uterus (3) osteo\u2013cartilage dynamics during development by differential staining. No significant differences were observed between eco and vivo measurements for CRL and BPD in all examined concepti. CRL and BPD, instead, showed a significant positive linear correlation with gestational age. The study of osteogenesis dynamics has demonstrated a completely cartilaginous ovine fetus at up to 35 days of gestation. The ossification begins in the skull (40th day) and is almost complete between the 65th and the 70th of pregnancy. Our study highlighted that CRL and BPD are accurate parameters for gestational age estimation in the first part of sheep pregnancy and provides an overview of osteochondral temporal dynamics. Furthermore, tibia ossification is a valid parameter to estimate fetal age by ultrasound.<\/jats:p>","DOI":"10.3390\/ani13050773","type":"journal-article","created":{"date-parts":[[2023,2,22]],"date-time":"2023-02-22T04:33:56Z","timestamp":1677040436000},"page":"773","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Fetal Growth and Osteogenesis Dynamics during Early Development in the Ovine Species"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4901-9904","authenticated-orcid":false,"given":"Sara","family":"Succu","sequence":"first","affiliation":[{"name":"Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Efisiangelo","family":"Contu","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale della Sardegna, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5277-5698","authenticated-orcid":false,"given":"Daniela","family":"Bebbere","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8579-3799","authenticated-orcid":false,"given":"Sergio Domenico","family":"Gadau","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura","family":"Falchi","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefano Mario","family":"Nieddu","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sergio","family":"Ledda","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"571","DOI":"10.1152\/physrev.00053.2003","article-title":"Developmental origins of the metabolic syndrome: Prediction, plasticity, and programming","volume":"85","author":"McMillen","year":"2005","journal-title":"Physiol. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1071\/RD10226","article-title":"Does size matter in females? An overview of the impact of the high variation in the ovarian reserve on ovarian function and fertility, utility of anti-Mullerian hormone as a diagnostic marker for fertility and causes of variation in the ovarian reserve in cattle","volume":"23","author":"Ireland","year":"2011","journal-title":"Reprod. Fertil. Dev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1016\/j.reprotox.2005.04.007","article-title":"Intrauterine growth restriction-etiology and consequences: What do we know about the human situation and experimental models?","volume":"20","author":"Ergaz","year":"2005","journal-title":"Reprod. Toxicol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2316","DOI":"10.2527\/jas.2006-156","article-title":"Board-invited review: Intrauterine growth retardation: Implications for the animal sciences","volume":"84","author":"Wu","year":"2006","journal-title":"J. Anim. Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2203738","DOI":"10.1002\/advs.202203738","article-title":"Placental MRI Predicts Fetal Oxygenation and Growth Rates in Sheep and Human Pregnancy","volume":"9","author":"Flouri","year":"2022","journal-title":"Adv. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"641","DOI":"10.1071\/RD05030","article-title":"Fluoxetine during pregnancy: Impact on fetal development","volume":"17","author":"Morrison","year":"2005","journal-title":"Reprod. Fertil. Dev."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"S41","DOI":"10.1016\/j.placenta.2006.11.002","article-title":"Animal models of human placentation-a review","volume":"28","author":"Carter","year":"2007","journal-title":"Placenta"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Banstola, A., and Reynolds, J.N.J. (2022). The Sheep as a Large Animal Model for the Investigation and Treatment of Human Disorders. Biology, 11.","DOI":"10.3390\/biology11091251"},{"key":"ref_9","unstructured":"Dyce, K.M., Sack, W.O., and Wensing, C.J.G. (2010). Textbook of Veterinary Anatomy, Elsevier. [4th ed.]."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"560","DOI":"10.1016\/0002-9378(95)90424-7","article-title":"Ultrasonographic assessment of fetal growth: Comparison between human and ovine fetus","volume":"173","author":"Barbera","year":"1995","journal-title":"Am. J. Obstet. Gynecol."},{"key":"ref_11","first-page":"257","article-title":"Estimation of gestational age using ultrasonography in Baluchi sheep","volume":"13","author":"Azizzadeh","year":"2022","journal-title":"Vet. Res. Forum"},{"key":"ref_12","first-page":"91","article-title":"Comparation of Foetal Growth in Natural Mated and Vitrified\/Warmed Ovine Embryos by Ultrasonographic Measurements","volume":"12","author":"Nieddu","year":"2014","journal-title":"Glob. Vet."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1016\/j.anireprosci.2018.08.028","article-title":"B-mode ultrasonography and ecobiometric parameters for assessment of embryonic and fetal development in sheep","volume":"197","author":"Taira","year":"2018","journal-title":"Anim. Reprod. Sci."},{"key":"ref_14","unstructured":"McGeady, T.A., Quinin, P.J., Fizpatrich, E.S., and Rayon, M.T. (2006). Veterinary Embryology, Wiley-Blackwell."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1007\/978-1-62703-989-5_9","article-title":"Whole-Mount Skeletal Staining","volume":"1130","author":"Rigueur","year":"2014","journal-title":"Methods Mol. Biol."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Vernunft, A., Eggert, A., and Br\u00fcssow, K.-P. (2023). Ultrasonographic Monitoring of Fetal Growth and Fetal Weight Calculation in Sows during Gestation. Agriculture, 13.","DOI":"10.3390\/agriculture13010016"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1046\/j.1439-0442.1999.00221.x","article-title":"Intrauterine growth retardation as a cause of perinatal mortality in Japanese black beef calves","volume":"46","author":"Ogata","year":"1999","journal-title":"J. Vet. Med."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/S1701-2163(15)30664-2","article-title":"Diagnostic Imaging Committee. Determination of gestational age by ultrasound","volume":"36","author":"Butt","year":"2014","journal-title":"J. Obstet. Gynaecol. Can."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1016\/j.theriogenology.2018.11.012","article-title":"Transrectal three-dimensional fetal volumetry and crown-rump length measurement during early gestation in mares: Intra- and inter-observer reliability and agreement","volume":"126","author":"Becsek","year":"2019","journal-title":"Theriogenology"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4534","DOI":"10.3168\/jds.2021-21006","article-title":"Variability of bovine conceptus-related volumes in early pregnancy measured with transrectal 3-dimensional ultrasonography","volume":"105","author":"Rotheneder","year":"2022","journal-title":"J. Dairy Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1437","DOI":"10.7863\/ultra.16.06069","article-title":"Quantitative ultrasound texture analysis for differentiating preterm from term fetal lungs","volume":"36","author":"Ghorayeb","year":"2017","journal-title":"J. Ultrasound Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1016\/j.ultrasmedbio.2021.08.020","article-title":"Prediction of lung maturity in fetuses with growth restriction through quantitative ultrasound analysis","volume":"48","author":"Zamarian","year":"2022","journal-title":"Ultrasound Med. Biol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"332","DOI":"10.4274\/jcrpe.galenos.2019.2019.0091","article-title":"Metabolic bone disease in premature neonates: An unmet challenge","volume":"12","author":"Chacham","year":"2020","journal-title":"J. Clin. Res. Pediatr. Endocrinol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"725","DOI":"10.1111\/rda.13163","article-title":"Qualitative and quantitative ultrasound attributes of maternal-foetal structures in pregnant ewes","volume":"53","author":"Uscategui","year":"2018","journal-title":"Reprod. Domest. Anim."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1293","DOI":"10.1071\/AR9891293","article-title":"Estimation of gestational age in Merino ewes by ultrasound measurement of fetal head size","volume":"40","author":"Kelly","year":"1989","journal-title":"Aust. J. Agric. Res."},{"key":"ref_26","first-page":"493","article-title":"Measurement of foetal growth via transabdominal ultrasonography during first half of pregnancy at ewes from synthetic population Bulgarian milk","volume":"18","author":"Metodiev","year":"2012","journal-title":"Bulg. J. Agric. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"437","DOI":"10.1016\/0301-6226(84)90055-1","article-title":"Diagnosis of pregnancy and number of foetuses in sheep by real- time ultrasonic imaging. Effects of number of foetuses, stage of gestation, operator, and breed of ewe on accuracy of diagnosis","volume":"11","author":"Fowler","year":"1984","journal-title":"Livest. Prod. Sci."},{"key":"ref_28","first-page":"37","article-title":"Utiliza\u00e7\u00e3o da ultrassonografia por via transretal em vacas da ra\u00e7a girolando para acompanhamento do desenvolvimento embrion\u00e1rio e\/ou fetal 26 a 181 dias de gestacao","volume":"3","author":"Menezes","year":"2011","journal-title":"Nucl. Anim."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1017\/S0021859600037230","article-title":"Studies on reproduction in prolific ewes. A radiographic study of the primary and secondary ossification centers in the fetus","volume":"88","author":"Wenham","year":"1977","journal-title":"J. Agric. Sci."},{"key":"ref_30","first-page":"52","article-title":"A study of the prenatal ossification centers and epiphyseal ossification in the limb bones of the goat","volume":"42","author":"Dhingra","year":"1972","journal-title":"Vet. Bull."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"529","DOI":"10.1292\/jvms.58.529","article-title":"Radiographical evaluation of bone maturation in Japanese black beef cattle","volume":"58","author":"Oishi","year":"1996","journal-title":"J. Vet. Med. Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1017\/S0021859600057142","article-title":"A radiographic study of skeletal growth and development in the pig. Temporal pattern of growth","volume":"80","author":"Wenham","year":"1973","journal-title":"J. Agric. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1016\/S0007-1935(17)39201-1","article-title":"Radiographic appearance of the centers of ossification of the limb bones in the feline fetus","volume":"124","author":"Boyed","year":"1968","journal-title":"Br. Vet. J."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1002\/ar.1092030211","article-title":"A radiographic study of the longitudinal growth of primary ossification centers in limb long bones of the human fetus","volume":"203","author":"Bagnall","year":"1982","journal-title":"Anat. Rec."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"394","DOI":"10.1002\/jcu.20156","article-title":"Sonographic identification and measurement of the epiphyseal ossification centers as markers of fetal gestational age","volume":"33","year":"2005","journal-title":"J. Clin. Ultrasound"},{"key":"ref_36","first-page":"e79940","article-title":"Evaluation of bi-iliac distance and timing of ossification of sacrum by sonography in the second trimester of pregnancy","volume":"16","author":"Moradi","year":"2019","journal-title":"Iran. J. Radiol."},{"key":"ref_37","first-page":"50","article-title":"The embryonic development of the sternum in sheep and goats","volume":"7","author":"Ahmed","year":"2008","journal-title":"J. Vet. Med. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1016\/S0007-1935(17)49057-9","article-title":"Observations on the loci of ossification in the prenatal and neonatal bovine skeleton. I. The appendicular skeleton","volume":"125","author":"Lindsay","year":"1969","journal-title":"Br. Vet. J."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1111\/j.1439-0264.1996.tb00078.x","article-title":"Osteogenesis of the fetal bovine skull","volume":"25","author":"Soana","year":"1996","journal-title":"Anat. Histol. Embryol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"251","DOI":"10.2217\/iim.10.14","article-title":"Cranial development in the first trimester: The use of 3D in the study of complex structures","volume":"2","author":"Rosignoli","year":"2010","journal-title":"Imaging Med."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1111\/joa.13184","article-title":"Fetal bone development in the lowland paca (Cuniculus paca, Rodentia, Cuniculidae) determined using ultrasonography","volume":"237","author":"Silva","year":"2020","journal-title":"J. Anat."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"741","DOI":"10.1111\/joa.13724","article-title":"Ultrasound evaluation of fetal bone development in the collared (Pecari tajacu) and white-lipped peccary (Tayassu pecari)","volume":"241","author":"Valsecchi","year":"2022","journal-title":"J. Anat."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"2188","DOI":"10.1098\/rspb.2011.2481","article-title":"Skeletal development in the African elephant and ossification timing in placental mammals","volume":"279","author":"Hautier","year":"2012","journal-title":"Proc. R. Soc. B Biol. Sci."},{"key":"ref_44","first-page":"24","article-title":"Sequential pattern of prenatal ossification in the fore limb bones in white New Zealand rabbits by double stained techniques and computed tomography","volume":"4","author":"Kamal","year":"2019","journal-title":"PSM Vet. Res."},{"key":"ref_45","first-page":"175","article-title":"The timing of mineralization of the limb bones, and growth rates of various long bones of the fore and hind limbs of the prenatal and early postnatal laboratory mouse","volume":"186","author":"Patton","year":"1995","journal-title":"J. Anat."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1258\/002367776781035161","article-title":"Skeletal development in the foetal and neonatal marmoset (Callithrix jacchus)","volume":"10","author":"Phillips","year":"1976","journal-title":"Lab. Anim."},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Starck, J.M., and Ricklefs, R.E. (1998). Avian Growth and Development. Evolution within the Altricial Precocial Spectrum, JM Stark & RE Ricklefs, Oxford University Press.","DOI":"10.1093\/oso\/9780195106084.001.0001"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1148\/radiol.2332030131","article-title":"Skeletal development in fetal pig specimens: MR imaging of femur with histological comparison","volume":"233","author":"Connolly","year":"2004","journal-title":"Radiology"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s12917-017-1092-6","article-title":"Small-sized newborn dogs skeletal development: Radiologic, morphometric, and histological findings obtained from spontaneously dead animals","volume":"13","author":"Modina","year":"2017","journal-title":"BMC Vet. Res."},{"key":"ref_50","first-page":"421746","article-title":"Biology of bone tissue: Structures, function, and factors that influence bone cells","volume":"2015","author":"Sasso","year":"2015","journal-title":"BioMed Res. Int."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1017\/S1751731113001614","article-title":"Maternal behavior and lamb survival: From neuroendocrinology to practical application","volume":"8","author":"Dwyer","year":"2014","journal-title":"Animal"}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/13\/5\/773\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T18:38:01Z","timestamp":1760121481000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/13\/5\/773"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,2,21]]},"references-count":51,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2023,3]]}},"alternative-id":["ani13050773"],"URL":"https:\/\/doi.org\/10.3390\/ani13050773","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,2,21]]}}}