Pregnancy diagnosis in swine by palpation and by amplitude-depth ultrasound scanning

The relative accuracy of two pregnancy testing methods for swine were compared in a field study. The procedures used were manual palpation and amplitude-depth ultrasonic scanning. A total of 369 sows were examined by both methods. Seven additional gilts were examined by ultrasound only and 46 sows by palpation per rectum only. The number of correct positive and negative diagnoses made by both methods were calculated, and determination of accuracy as well as comparison between the tests were made on this basis. The relative accuracy was 97.6% for the manual method and 96.8% for the ultrasound method. Both tests had a high sensitivity, 99.2 and 98.9%, respectively. The ability of the tests to detect the non-pregnant animals was not as high, which is reflected by a lower specificity. No significant differences were noted between the two methods. A lower specificity and a lower negative predictive value were provided by ultrasound scanning as compared with those acquired by manual palpation. Both procedures were considered to be quick and convenient to perform. It was concluded that in spite of the new pregnancy testing methods introduced in the swine industry, manual palpation remains the most practical in terms of its accuracy, ease, and the minimal requirement for equipment. In gilts, palpation is unsuitable and ultrasonography currently remains the best choice for the diagnosis of pregnancy.     

Gynecological examination and pregnancy diagnosis in small ruminants using bimanual palpation technique: a review

A palpation technique using both hands was developed by the author and used for examination of internal reproductive organs, pregnancy diagnosis, and assessment of approximate stages of gestation in small ruminants. The study was conducted in 4 stages on 87 female goats and 30 slaughterhouse source ewes First, 20 doelings and 15 does with no recent history of insemination were examined by two hand method for palpability and structural integrity of internal reproductive organs. Next 52 goats (28 doelings and 24 does) were examined at 28 to 30 d post insemination for pregnancy. Among those diagnosed pregnant, 20 goats were examined at 15 d intervals to assess the palpable changes of pregnancy. Preslaughter palpation followed by post-slaughter verification of the findings were performed in 30 ewes. The two hand method was effective for palpating the reproductive tract in the nonpregnant goats irrespective of parity status. Gross palpation of the ovaries was possible in 83% of the goats. Of the 52 goats examined for pregnancy at 28 to 30 d, 29 (56%) had clear distension of uterus while 23 (44%) did not. The results were confirmed by kidding date or returning to service. Changes of the reproductive tract were monitored in 20 goats at biweekly intervals and the findings categorized by the stage of gestation. Post slaughter verification of preslaughter findings based on two handed palpation indicates that this technique can be used for early pregnancy diagnosis and assessment of the stage of gestation in goats and ewes.     

Progesterone levels and relationship with the diagnosis of a corpus luteum by rectal palpation during the estrous cycle in Zebu cows

To assess the accuracy of rectal palpation for detecting functional luteal tissue during the estrous cycle in Zebu cattle, 20 mature non-lactating Indobrazil cows were palpated twice weekly for 7 1/2 weeks. Blood samples were drawn for progesterone analyses at each palpation. Circulating serum progesterone levels were below 0.5 ng/ml from days 0-4 (Day 0 = day of estrus); they increased thereafter, reaching maximum levels of 3.1 ng/ml on days 9 and 10. Values declined sharply to less than 0.5 ng/ml on day 18. Regardless of the stage of the estrous cycle in 71.3% of the cases (117 out of a total of 164 observations) the circulating progesterone levels corresponded to the results of rectal examination. The criteria to assess this relationship were that the presence of CL as determined by rectal palpation would be accompanied by levels of progesterone higher than 0.5 ng/ml, whereas absence of CL would be accompanied by levels less than 0.5 ng/ml. The correlation was significantly higher (P<0.05) on days 5-17 (77.9%) than on days 0-4 (57.5%) and 18-20 (65%). To assess the correlation of both rectal examination and progesterone levels with the stage of the estrous cycle, we expected that on days 0-4 and 18-20 no palpable CL and progesterone levels less than 0.5 ng/ml would occur, whereas on days 5-17 palpable CL and progesterone levels higher than 0.5 ng/ml would be found. On this basis, a correlation of 45% (18 out of 40 observations) between expected and observed values was found on days 0-4, 76% (79 out of 104) on days 5-17 and 60% (12 out of 20) on days 18-20 of the estrous cycle. Of the total of 55 observations which fell outside the expected values, 71% was due to a wrong diagnosis of CL; 14.5% was due to progesterone levels higher or lower than the expected values, and 14.5% to both laboratory and rectal palpation findings.     

A comparison of diagnosis of pregnancy in the goat via transrectal ultrasound scanning, progesterone, and pregnancy-associated glycoprotein assays

Real-time ultrasound scanning (US) via the transrectal route, progesterone (P4) assay, and pregnancy-associated glycoprotein (PAG) detection can be used to diagnose pregnancy at around 3 weeks after breeding. Although several studies have been carried out to evaluate each of these different methods individually, it is difficult to establish adequate comparisons due to differences, such as the breed of goat, age, and farming conditions, among others. The aim of the present paper is to compare the accuracy of diagnosis of pregnancy using transrectal US, P4 assay and PAG detection at the same time and on the same animals. Canary dairy goats (n=143) were synchronized with an 11-day fluorogestone acetate (FGA) intravaginal sponge followed by PGF2alpha and eCG 2 days before the FGA withdrawal. Blood samples were collected on Days 20, 22, 24, and 26 after mating to determine P4 and PAG concentrations. Transrectal US examinations were performed at the same time. There were 79 pregnant goats and another 64 non-pregnant. The US via the transrectal method and the determination of PAG concentrations provide very accurate pregnancy diagnosis at 24-26 days after breeding; on the contrary, P4 assay on plasma samples performed on Day 22 after breeding was accurate, in this case, in detecting pregnant animals but did not always detect the non-pregnant does.     

A comparison between plasma oestrone sulphate concentration and doppler ultrasound as methods for pregnancy diagnosis in sows

Plasma oestrone sulphate (E(1)S) concentration and doppler ultrasound as methods of pregnancy diagnosis in sows were compared. Using either method, pregnancy was accurately detected (test sensitivity > 94% for pregnant sows). E(1)S was a better predictor of nonpregnant animals (test specificity 78 vs 66%, respectively; P < 0.01) and could be used at least 1 wk earlier than doppler ultrasound (24 to 30 d vs 35 d postservice, respectively). E(1)S concentration was not an accurate predictor of litter size.     

Fetal survival in the cow after pregnancy diagnosis by palpation per rectum

It is desirable to determine wheter a cow has failed to become pregnant as early as possible, preferably prior to 50 d after insemination. Although palpation per rectum has been the generally accepted method of pregnancy diagnosis in cattle, the procedure may be a significant iatrogenic cause of fetal attrition. In a study conducted at a North Florida dairy from January through June 1982, pregnancy was determined in 192 Holstein-Friesian cows by measuring low milk progesterone (P4) content on day of insemination (Day 0) and elevated P4 on Days 21 and 24. Pregnant cows were randomly assigned to a treatment and a control group. Cows in the treatment group (n = 85) were palpated per rectum twice between Days 42 and 46 after insemination. Cows in the control group (n = 107) were not palpated until both groups were palpated at Day 90. Palpation, done by two experienced clinicians, consisted of palpation of fetal fluid fluctuation, identification of the amniotic vesicle, and slipping of the chorioallantoic membranes. In both groups of cows fetal viability was monitored by milk P4 content. Last milk (5 to 15 ml) was collected from one front quarter on Days 0, 21, and 24 and twice weekly thereafter through Day 63. Milk was defatted by centrifugation and the fat-free milk progesterone content measured by a radioimmunoassay without extraction. The milk P4 test was 80.0% accurate in determining pregnancy in the palpated and nonpalpated cows. In the cows palpated on Days 42 to 46, pregnancy rates declined by 7.5% as determined by palpation at Day 90, or by 11.4% as determined by milk P4 content through Day 63 (both values P < 0.05). Cows that were not palpated on Days 42 to 46 showed a 1.9% increase or a 4.3% decline in pregnancy rates as determined by the same criteria. Before palpation, at Days 42 to 46, pregnancy rates were better in cows that were inseminated in winter (January to March) than in spring (April to June) (82.3% vs 61.6%; P < 0.05); P4 content was higher (winter > spring = 2.13 ng/ml vs 1.38 ng/ml; P < 0.05). First-lactation cows had higher P4 values on Days 21 and 24 than older cows (P < 0.01).     

A simple technique for experimental hepatic vein catheterization in swine

Hepatic vein catheterization is a valuable technique in studies of hepatic physiology and metabolism. A new technique for hepatic vein catheterization in swine is described which avoids fluoroscopy, incision, or puncture of the hepatic parenchyma. Experience with this new technique in over 40 studies of young pigs has confirmed the reliability of the technique. Management of hepatic vein catheters after insertion and potential sources of error in hepatic venous sampling are discussed.     

A model for economic comparison of swine insemination programs

Optimal artificial insemination schedules are those that result in a high farrowing rate and litter size, while minimizing costs of semen and labor by avoiding unnecessary inseminations. A simulation model programmed in a commercial spreadsheet was developed to permit comparison of alternative schedules. Farrowing rate and litter size for a particular schedule were dependent on the timing of insemination relative to the time of ovulation. Economic return was calculated by multiplying the number of pigs born per bred sow by $33.00 and subtracting the cost of producing a litter of pigs and raising them to weaning ($222.88 per sow plus $2.44 per pig born) and the cost of detection of estrus and breeding. Seven insemination schedules combined with once versus twice per day detection of estrus were simulated in 500 herds of 100 sows each. Inseminations were simulated to occur on schedules of: 1) 0, 12, 24 and 36 h; 2) 12, 24 and 36 h; 3) 0 and 24 h; 4) 12 and 36 h; 5) 12 h; 6) 24 h; and 7) 36 h after first detection of estrus. Schedule 1 was predicted to yield the highest farrowing rate and litter size. Economic return was highest for Schedule 2 with twice per day detection of estrus followed closely by Schedule 1 with once per day detection of estrus at $14.90 and $13.75 per bred sow, respectively. High performance was dependent on insuring that inseminations occurred at an optimum time in as great a proportion of sows as possible.     

Pregnancy diagnosis and abnormalities of pregnancy in the dog

New and traditional techniques for pregnancy diagnosis in the dog are reviewed. Imaging techniques yield the most information, with ultrasonography the preferred technique for assessment of fetal viability and radiography the preferred technique for assessment of litter size. Diabetes mellitus and pregnancy toxemia are uncommon complications of pregnancy. Pathogenesis, diagnosis and treatment of infectious and non-infectious causes of pregnancy loss are reviewed.     

A comparison of portable ultrasound and fully-equipped clinical ultrasound unit in the thyroid size measurement of the Indo-Pacific bottlenose dolphin

Measurement of thyroid size and volume is a useful clinical parameter in both human and veterinary medicine, particularly for diagnosing thyroid diseases and guiding corrective therapy. Procuring a fully-equipped clinical ultrasound unit (FCUS) may be difficult in most veterinary settings. The present study evaluated the inter-equipment variability in dolphin thyroid ultrasound measurements between a portable ultrasound unit (PUS) and a FCUS; for both units, repeatability was also assessed. Thyroid ultrasound examinations were performed on 15 apparently healthy bottlenose dolphins with both PUS and FCUS under identical scanning conditions. There was a high level of agreement between the two ultrasound units in dolphin thyroid measurements (ICC = 0.859–0.976). A high intra-operator repeatability in thyroid measurements was found (PUS: ICC = 0.854–0.984, FCUS: ICC = 0.709–0.954). As a conclusion, no substantial inter-equipment variability was found between PUS and FCUS in dolphin thyroid size measurements under identical scanning conditions, supporting further application of PUS for quantitative analyses of dolphin thyroid gland in both research and clinical practices at aquarium settings.     

The role of endoscopic ultrasound in the evaluation of rectal cancer

Accurate staging of rectal cancer is essential for selecting patients who can undergo sphincter-preserving surgery. It may also identify patients who could benefit from neoadjuvant therapy. Clinical staging is usually accomplished using a combination of physical examination, CT scanning, MRI and endoscopic ultrasound (EUS). Transrectal EUS is increasingly being used for locoregional staging of rectal cancer. The accuracy of EUS for the T staging of rectal carcinoma ranges from 80-95% compared with CT (65-75%) and MR imaging (75-85%). In comparison to CT, EUS can potentially upstage patients, making them eligible for neoadjuvant treatment. The accuracy to determine metastatic nodal involvement by EUS is approximately 70-75% compared with CT (55-65%) and MR imaging (60-70%). EUS guided FNA may be beneficial in patients who appear to have early T stage disease and suspicious peri-iliac lymphadenopathy to exclude metastatic disease.     

A comparison of healthy human and swine articular cartilage dynamic indentation mechanics

Articular cartilage is a multicomponent, poroviscoelastic tissue with nonlinear mechanical properties vital to its function. A consequent goal of repair or replacement of injured cartilage is to achieve mechanical properties in the repair tissue similar to healthy native cartilage. Since fresh healthy human articular cartilage (HC) is not readily available, we tested whether swine cartilage (SC) could serve as a suitable substitute for mechanical comparisons. To a first approximation, cartilage tissue and surgical substitutes can be evaluated mechanically as viscoelastic materials. Stiffness measurements (dynamic modulus, loss angle) are vital to function and are also a non-destructive means of evaluation. Since viscoelastic material stiffness is strongly strain rate dependent, stiffness was tested under different loading conditions related to function. Stiffness of healthy HC and SC specimens was determined and compared using two non-destructive, mm-scale indentation test modes: fast impact and slow sinusoidal deformation. Deformation resistance (dynamic modulus) and energy handling (loss angle) were determined. For equivalent anatomic locations, there was no difference in dynamic modulus. However, the HC loss angle was ~35% lower in fast impact and ~12% higher in slow sinusoidal mode. Differences seem attributable to age (young SC, older HC) but also to species anatomy and biology. Test mode-related differences in human-swine loss angle support use of multiple function-related test modes. Keeping loss angle differences in mind, swine specimens could serve as a standard of comparison for mechanical evaluation of e.g. engineered cartilage or synthetic repair materials.     

A single radial hemolysis technique for the measurement of influenza virus antibody in swine serum

A single radial hemolysis technique was applied to the measurement of swine influenza virus antibody in swine serum. It was recognized to be useful for the detection of this antibody, although heating at 56 degrees C for 30 minutes was necessary to remove non--specific hemolysis from the test sample. The single radial hemolysis titer was correlative with the hemagglutination--inhibition titer in serum from pigs infected experimentally or naturally. This technique is simple, rapid and unaffected with non--specific inhibitors in swine serum. It does not require concentrated purified virus either. Therefore, it is applicable to the sero--epizootiologic surveillance of swine influenza on a large scale.