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A 5-MHz sector transducer (experiment 1) and a 7.5 MHz linear-array transducer (experiment 2) were used for early pregnancy diagnosis in two Hungarian dairy herds under field conditions. In the first experiment, ultrasound scanning was conducted three times at 3 or 4-day intervals between 24 and 33 days after artificial insemination (AI), while in the second experiment, it was performed two times at 7-day intervals between 27 and 38 days post-insemination. Significantly more incorrect non-pregnancy diagnoses were made between 24 and 33 days (first experiment) and between 27 and 38 days (second experiment) after AI in cows in which the uterus was located far cranial to the pelvic inlet than in animals in which the uterus was located within or close to the pelvic inlet at the first ultrasonographic examination.

A transabdominal Doppler technique for the recording of fetal heart rate (FHR) was investigated in the bovine fetus. During the last 2 weeks of gestation recordings were made once or twice per week in eight cows by placing a 1.5 MHz Doppler transducer on the right ventral abdominal wall. Continuous FHR recordings with a duration of more than 30 min were obtained in 29 of the 35 sessions. Major displacements of the fetus were the main cause of recording failure. The overall mean baseline FHR was 105 +/- 1.5 bpm with a range of 90 to 125 bpm. The mean bandwidth of the baseline FHR was 10.8 +/- 0.7 bpm with a range of < 5 to 20 bpm. Periods with different bandwidths alternated. The alternation of bovine FHR patterns pointed to the existence of different fetal behavioural states. The mean number of accelerations of FHR was 7.1 +/- 1.0 per hour. Many of the accelerations coincided with visible or perceptible fetal body movements. Decelerations of FHR occurred less frequently (range 0 to 4 per h). A period of tachycardia accompanied by an increased number of fetal movements occurred in 3 of the 29 FHR recordings. This non-invasive technique appears to be suitable to study FHR patterns during gestation and to investigate the presence and characteristics of behavioural states in the bovine fetus. It also provides the possibility to study effects on the fetus of drugs administered to the dam.

The use of a transabdominal or a transrectal scanning technique to visualize the uterus in goats is discussed. The results of sonographic imaging of normal (non-pregnant, pregnant, postpartum) and abnormal (endometritis, hydrometra, fetal death) uterine structures are reviewed. In the goat, special attention must be paid to distinguishing between the sonographic image of hydrometra and early pregnancy. A case of hydrometra that developed in the presence of three dead fetuses is reported. It is concluded that, under field conditions, transabdominal scanning of goats, performed between days 40 and 70 after mating, yields information about pregnancy, fetal viability, and single or multiple pregnancy, while at the same time making possible a reliable differential diagnosis of pregnancy and hydrometra.

Summary Parturition was induced in 112 gilts and sows on day 111, 112, and 113 of gestation by means of a single intramuscular injection of 175 mcg of a prostaglandin F2α analogue (Cloprostenol, I.C.I. 80996). No side effects were detected immediately after injection and the course of the induced parturition was normal. The interval between injection and parturition was approximately 28 hours. Induction of parturition on day 113 resulted in a significant shortening of this interval as compared with day 111 and 112. The average weights of the piglets at birth and at 5 weeks were within the normal range. The percentage of stillbirths and the loss of piglets up to weaning did not differ significantly between control and experimental groups. The practical applications of induction of parturition are discussed.

This paper presents quantitative results of canine pregnancy diagnoses performed by abdominal palpation and/or linear-array real-time echography. Each animal was first palpated by an experienced clinician and then another investigator performed ultrasound scanning using a 3 MHz transducer. In other dogs echography was undertaken only when the result of abdominal palpation was negative or doubtful or when the owner requested ultrasound scanning. Using all tests performed between days 20 and 49 of pregnancy (day 0 = day of first mating or insemination), the results of abdominal palpation (n = 116) versus real-time scanning (n = 135) were: sensitivity: 89.0% v 92.9%; specificity: 93% v 96.0%; positive predictive value: 95.6% v 97.5%; negative predictive value: 83.3% v 88.9%. Results of ultrasound tests performed in 97 other dogs were: sensitivity: 92.4%; specificity: 97.7%; positive predictive value: 98.0% and negative predictive value: 91.4%. Almost identical figures were found when only the tests performed between days 25 and 35 of pregnancy were included. It was concluded that real-time ultrasound scanning is an accurate method for discriminating between pregnant and non-pregnant bitches; sensitivity and specificity of the abdominal palpation technique executed by an experienced clinician approach that of ultrasound scanning; small litter size and lack of knowledge of conception date are the main sources of false negative diagnoses.

The acid-base status of 58 calves (all in normal anterior presentation) was determined from venous blood samples before the onset of traction and immediately after vaginal delivery. Calves were assigned to one of three groups according to their blood pH value: group 1 - normal, pH greater than 7.2; group 2 - acidotic, pH 7.2 to 7.0; group 3 - severely acidotic, pH less than 7.0. Before the onset of traction (i.e. during the 30 minutes following the appearance and rupture of the membranes), 43 calves (74.1%) had normal acid-base values, 14 (24.1%) had slight acidosis, and only 1 (1.7%) had severe acidosis. At birth the three groups of calves showed the following distribution: 23 (39.7%) were normal, 29 (50%) had slight acidosis, and 6 (10.3%) had severe acidosis. Seven calves (12.1%) died during birth or within 48 hours after birth; 2 were normal shortly before birth, 4 were acidotic shortly before birth, and 1 was severely acidotic even before the onset of traction. Traction was significantly longer for cows that delivered severely acidotic calves compared to cows in the other two groups.

Pregnancy diagnosis was carried out in sheep by means of transabdominal linear-array real-time ultrasound scanning. Animals were restrained standing, and the transducer was placed on the hairless area of the ventral abdominal wall just in front of the udder. Of a total of 818 tests, 724 were performed between days 29 and 89 of pregnancy, 598 animals subsequently lambed and 126 were non-lambing animals. Only 8 of these tests were wrong: 3 false positive and 5 false negative diagnoses. Sensitivity, specificity, positive- and negative predictive values for these tests were 99.2%, 97.6%, 99.5%, and 96% respectively. There was evidence to indicate that the three false positive tests were caused by foetal mortality or unobserved abortions that took place after testing. Only 2 of the 5 false negative tests were carried out after day 39 of gestation. Counting of foetal numbers (1, 2 or 3) was performed in only some animals (n = 210) between days 45 and 77 of gestation. Three groups of animals (A: 89 ewes; B: 27 PMSG-treated ewes; C: 94 ewes) were analyzed separately. Overall accuracy of all predictions was 83.1%, 37.0% and 78.7% for the 3 groups respectively. Animals in group B produced only 3 or more lambs. Sensitivity of the countings of singles, twins and triplets or more were 90.4%, 90.4% and 50% respectively for the animals from group A and 91.9%, 86% and 21.4% for the animals from group C.(ABSTRACT TRUNCATED AT 250 WORDS)

Between days 24 and 32 after mating/insemination, 881 pigs (785 pregnant and 96 not-pregnant) were tested for pregnancy on a commercial farm with a linear-array real-time ultrasound scanner. 5-7 Days later, 785 of these animals (708 pregnant and 77 not-pregnant) were tested again with A-mode equipment by farm employees. Confirmation of pregnancy was based on recorded farrowings or abortions; confirmation of non-pregnancy was based on return to oestrus and rebreeding, recorded non-farrowing, or inspection of the uterus of culled animals at the slaughterhouse. From the number of correct positive (a), incorrect positive (b), correct negative (c) and incorrect negative (d) diagnoses, a sensitivity (a/a + d) of 100% versus 97.5%, a specificity (c/c + b) of 90.6 versus 55.8%, a positive predictive value (a:a + b) of 98.9% versus 95.3% and a negative predictive value (c:c + d) of 100% versus 70.5% were calculated for the real-time ultrasound technique versus A-mode technique. It was concluded that real-time ultrasound scanning provides a very accurate technique for pregnancy diagnosis in pigs, enabling immediate decision making on treatment or culling of animals diagnosed as non-pregnant.

Pregnancy diagnoses were performed under farm conditions in 201 cows (Hungarian Red Pied and crossbreds with Holstein) between 21 and 70 days after last insemination date, using a linear-array real-time ultrasound scanner with a 3.0 MHz rectal transducer. Identification of (a) sharply demarcated black area(s) and/or an embryo within the uterus were used as criterions for pregnancy. Pregnancy was confirmed by rectal examination at 6 and/or 8 weeks after A.I. From the total number of correct positive diagnoses (n = 129), incorrect positive diagnoses (n = 3, made on days 36, 40 and 44 after A I), correct negative diagnoses (n = 62) and incorrect negative diagnoses (n = 7, made on days 25, 28, 28, 29, 30, 31, and 33 after A I), a sensitivity of 94.8%, a specificity of 95,3%, a positive predictive value of 97.7% and a negative predictive value of 89.8% were calculated. From these preliminary results it was concluded that real-time ultrasound scanning is a useful and reliable technique for early pregnancy diagnosis in cows. It is suggested that a combination of milk/plasma progesterone estimation between days 21 and 24 and real-time ultrasound scanning between days 25 and 45 would allow the confirmation and quantification of (late) embryonic mortality in the cow.