• Beccaglia M, Luvoni GC, 2006: Comparison of the accuracy of two ultrasonographic measurements in predicting the parturition date in the bitch. J Small Anim Pract 47, 670673.
  • Beccaglia M, Anastasi P, Grimaldi E, Rota A, Faustini M, Luvoni GC, 2008: Accuracy of the prediction of parturition date through ultrasonographic measurement of fetal parameters in the queen. Vet Res Commun 32(Suppl 1), S99S101.
  • Concannon PW, Whaley S, Lein D, Wissler R, 1983: Canine gestation length: variation related to time of mating and fertile life of sperm. Am J Vet Res 44, 18191821.
  • England GCW, Allen WE, Porter DJ, 1990: Studies on canine pregnancy using B-mode ultrasound: development of the conceptus and determination of gestational age. J Small Anim Pract 31, 324329.
  • Johnston SD, Root Kustritz MV, Olson PNS, 2001: Feline pregnancy. In: Johnston SD, Root Kustritz MV, Olson PNS (eds), Canine and Feline Theriogenology. WB Saunders Company, Philadelphia, PA, pp. 414430.
  • Karki DB, Sharmqa UK, Rauniyar RK, 2006: Study of accuracy of commonly used fetal parameters for estimation of gestational age. J Nepal Med Assoc. 45, 233237.
  • Kim Y, Travis AJ, Meyers-Wallen VN, 2007: Parturition prediction and timing of canine pregnancy. Theriogenology 68, 11771182.
  • Kutzler MA, Yeager AE, Mohammed HO, Meyers-Wallen VN, 2003: Accuracy of canine parturition date prediction using fetal measurements obtained by ultrasonography. Theriogenology 60, 13091317.
  • Lopate C, 2008: : Estimation of gestational age and assessment of canine fetal maturation using radiology and ultrasonography: a review. Theriogenology 70, 397402.
  • Luvoni GC, Beccaglia M, 2006: The prediction of parturition date in canine pregnancy. Reprod Domest Anim 41, 2732.
  • Luvoni GC, Grioni A, 2000: Determination of gestational age in medium and small size bitches using ultrasonography measurement of foetal structures. J Small Anim Pract 41, 292294.
  • Zambelli D, Castagnetti C, Belluzzi S, Bassi S, 2002: Correlation between the age of the conceptus and various ultrasonographic measurements during the first 30 days of pregnancy in domestic cats (Felis catus). Theriogenology 57, 19811987.