References

Ali, A. and M. Hayder, 2007. Ultrasonographic assessment of embryonic, fetal and placental development in Ossimi sheep. Small Ruminant Res., 73: 277-282.
CrossRef  |  

Azevedo, E.M.P., C.R.A. Filho, L.M.F. Neto, R.T.D. Moura and E.R. Santos Jr. et al., 2009. Ultrasonographic scan planes for sexing ovine and caprine fetuses. Med. Vet., 3: 21-29.
Direct Link  |  

Bowen, R., 2000. Placentation in ruminants. http://www.vivo.colostate.edu/hbooks/pathphys/reprod/placenta/ruminants.html.

Bretzlaff, K.N., 1993. Development of hydrometra in a ewe flock after ultrasonography for determination of pregnancy. J. Am. Vet. Med. Assoc., 203: 122-125.
PubMed  |  

Buckrell, B.C., 1988. Applications of ultrasonography in reproduction in sheep and goats. Theriogenology, 29: 71-84.
CrossRef  |  

Dawson, L.J., T. Sahlu, S.P. Hart, G. Detweiler and T.A. Gipson et al., 1994. Determination of fetal numbers in Alpine does by real-time ultrasonography. Small Ruminant Res., 14: 225-231.
Direct Link  |  

De Bulnes, A.G., J.S. Moreno and A.L Sebastian, 1998. Estimation of fetal development in Manchega dairy ewes by transrectal ultrasonographic measurements. Small Ruminant Res., 27: 243-250.
CrossRef  |  Direct Link  |  

Doize, F., D. Vaillancourt, H. Carabin and D. Belanger, 1997. Determination of gestational age in sheep and goats using trans-rectal ultrasonographic measurement of placentomes. Theriogenology, 48: 449-460.
CrossRef  |  

Garcia, A., M.K. Neary, G.R. Kelly and R.A. Pierson, 1993. Accuracy of ultrasonography in early pregnancy diagnosis in the ewe. Theriogenology, 39: 847-861.
CrossRef  |  

Goddard, P.J., 1995. Veterinary Ultrasonography. CAB International, Wallingford, Oxon.

Haibel, G.K., 1988. Real-time ultrasonic fetal head measurement and gestational age in dairy goats. Theriogenology, 30: 1053-1057.
PubMed  |  Direct Link  |  

Haibel, G.K., 1990. Use of Ultrasonography in Reproductive Management of Sheep and Goat Herds. In: Advances in Sheep and Goat Medicine. The Veterinary Clinics of North America Food Animal Practice, Smith, M.C. (Ed.). Vol. 6, W.B. Saunders, Philadelphia, pp: 597-613.

Jainudeen, M.R. and E.S.E. Hafez, 2000. Gestation, Prenatal Physiology and Parturition. In: Reproduction in Farm Animals, Hafez, E.S.E. and B. Hafez (Eds.). 7th Edn., Lippincott Williams and Wilkins, Philadelphia, pp: 140-155.

Kahn, W., J. Achtzehn, B. Kahn, A. Richter, J. Schulz and M. Wolf, 1993. Sonography of pregnancy in sheep. II. Accuracy of transrectal and transcutaneous pregnancy diagnosis. Dtsch. Tieraerztl. Wschr., 100: 29-31.
PubMed  |  

Karen, A.M., E.S.M. Fattouha and S.S. Abu-Zeid, 2009. Estimation of gestational age in Egyptian native goats by ultrasonographic fetometry. Anim. Reprod. Sci., 114: 167-174.

Kelly, R.W. and J.P. Newnham, 1989. Estimation of gestational age in Merino ewes by ultrasound measurement of fetal head size. Aust. J. Agric. Res., 40: 1293-1299.
Direct Link  |  

Lavoir, M.C. and M.A.M. Taverne, 1989. The Diagnosis of Pregnancy and Pseudopregnancy, and the Determination of Foetal Number in Goats, by Means of Real-Time Ultrasound Scanning. In: Diagnostic Ultrasound and Animal Reproduction, Taverne, M.M. and A.H. Willemse (Eds.). Kluwer Academic Publisher, Dordrecht, pp: 89-96.

Lee, Y., O. Lee, J. Cho, H. Shin and Y. Choi et al., 2005. Ultrasonic measurement of fetal parameters for estimation of gestational age in Korean black goats. J. Vet. Med. Sci., 67: 497-502.
CrossRef  |  PubMed  |  

Martinez, M.Z., P. Bosch and R.A. Bosch, 1998. Determination of early pregnancy and embryonic growth in goats by transrectal ultrasound scanning. Theriogenology, 49: 1555-1565.
Direct Link  |  

McDonald, Y., G. Wenham and J.J. Robinson, 1978. Studies on reproduction in prolific ewes. III. The development in size and shape on the foetal skeleton. J. Agric. Sci. Cambridge, 89: 375-391.

Medan, M., G. Watanabe, G. Absy, K. Sasaki, S. Sharawy and K. Taya, 2004. Early pregnancy diagnosis by means of ultrasonography as a method of improving reproductive efficiency in goats. J. Reprod. Dev., 50: 391-397.
PubMed  |  

Nizam, M.A.R., W.E.W. Khadijah and R.B. Abdullah, 2009. Accuracy of ultrasonographic assessment pregnancy related structures in Boer does. Proceedings of the International Conference on Animal Health and Human Safety, Dec. 6-8, Palm Garden Hotel, IOI Resort, Selangor, pp: 310-311.

Padilla-Rivas, G.R., B. Sohnrey and W. Holtz, 2005. Early pregnancy detection by real-time ultrasonography in Boer goats. Small Ruminant Res., 58: 87-92.
CrossRef  |  

Reichle, J.K. and G.K. Haibel, 1991. Ultrasonic biparietal diameter of second trimester Pygmy goat fetuses. Theriogenology, 35: 689-694.
CrossRef  |  

Robinson, J.J., I. McDonald, C. Fraser and R.M.J. Crofts, 1977. Studies on reproduction in prolific ewes. 1. Growth of the products of conception. J. Agric. Sci., 88: 539-552.

Romano, J.E., C.J. Christians and B.G. Crabo, 1998. Applications of transrectal ultrasonography in ewe reproduction. 1998 Minnesota Sheep Research Report, Dept. of Animal Science, Univ. of Minnesota, St. Paul, MN, pp: 81-82.

Romano, J.E., C.J. Christians and B.G. Crabo, 1998. Early pregnancy detection by transrectal ultrasonography in Suffolk Ewes. 1998 Minnesota Sheep Research Report, Dept. of Animal Science, Univ. of Minnesota, St. Paul, MN, pp: 83-86.

Schrick, F.N. and E.K. Inskeep, 1993. Determination of early pregnancy in ewes utilizing transrectal ultrasonography. Theriogenology, 40: 295-306.
PubMed  |  

Sergeev, L., D.O. Kleemann, S.K. Walker, D.H. Smith, T.I. Grosser, T. Mann and R.F. Seamark, 1990. Real-time ultrasound imaging for prediction ovine fetal age. Theriogenology, 34: 593-601.
PubMed  |  Direct Link  |  

Suguna, K., S. Mehrotra, S.K. Agarwal, M. Hoque, S.K. Singh, U. Shanker and T. Sarath, 2008. Early pregnancy diagnosis and embryonic and fetal development using real time B mode ultrasound in goats. Small Ruminant Res., 80: 80-86.
CrossRef  |  

Taverne, M.A., M.C. Lavoir, R. van Oord, G.C. van der Weyden, 1985. Accuracy of pregnancy diagnosis and prediction of foetal numbers in sheep with linear-array real-time ultrasound scanning. Vet. Q., 7: 256-263.
PubMed  |  

Yotov, S., 2005. Diagnostics of early pregnancy in Stara Zagora dairy sheep breed. Bulgarian J. Vet. Med., 8: 41-45.