THE ADVANTAGES AND SAVINGS FROM USING THE BLOOD PREGNANCY TEST COMPARED TO RECTAL PALPATION A PREGNANCY DETECTION SYSTEM FOR DAIRY CATTLE BioTracking 105 East Second Moscow, Idaho 83843 Web Site: www.boitracking.com E-mail: biotracking@turbonet.com Ph/Fax: 208 882 9736 BioTracking provides a complete service to dairies beginning with consulting on how to obtain, handle and ship blood and ending with laboratory testing and providing an electronic report for downloading into the computer management program of the dairy. BioTracking has eight years of experience testing serum samples of ruminant animals from across the United States and Canada and certain foreign countries. Major clients are breeders of dairy cattle, beef cattle, elk, deer, bison, goats and sheep and wildlife biologists who manage and study wild ruminant populations (elk, deer, mountain sheep and goats, caribou, moose and wood bison). Until this year, the test for cattle has been by radioimmunoassay. Recently, an enzyme-linked immuno-sorbent assay (ELISA) was established for dairy and beef cattle and provides an inexpensive test. This paper describes the Pregnancy Detection System of BioTracking for cattle. A Worksheet is provided so that breeders can compare costs of pregnancy testing by rectal palpation with the blood test. There are hidden costs in doing rectal exams and these can be avoided with the blood test. The reason for this savings is that blood testing is not invasive and the embryo/fetus is not touched. Touching is harmful to the embryo and abortion can occur. Calculation of these costs are provide and backed up by citation of scientific literature. Additionally, disease can be spread by doing rectal palpation. It is also shown herein that actual costs of professional labor and travel are high and that blood sampling can be done at less cost. Breeders are encouraged to complete the Worksheet, compare their own costs to the example provided and to find the economic advantage of the blood test. Various costs listed in the Worksheet are explained in pages that follow. Breeders are encouraged to substitute their cost-estimates to fit enterprise expenses. ABOUT THE TEST: The test measures presence of Pregnancy-Specific Protein B (PSPB). It is a protein that was discovered in the placenta of cattle by researchers at the University of Idaho (R. G. Sasser and students). The protein enters the blood of the mother and can be measured at BioTracking in this blood. BioTracking has a license from the university for use of PSPB in testing pregnancy and has developed a highly accurate and very inexpensive blood test (enzyme-linked immuno-sorbent assay, ELISA) for pregnancy. Samples of blood are collected on the dairy, ranch or farm and are mailed to BioTracking for analysis. Samples arriving by Tuesday will be tested over a three-day period and an e-mail, FAX, phone or mail (client's choice) report will be available by Saturday of each week. Results can be posted on a web site for access through a code by the client. Accuracy of the result is OVER 95% correct Volume of Sample: Just 1 cc of serum is needed (2cc of whole blood). Use a red topped or gray and red topped vacuum tube. When to test cattle: Heifers: 28 days after breeding. to term Lactating Cows: 30 days after breeding AND 90 days after calving to term Other Animals: All ruminant animals are tested. See the web site for time of sampling. How to ship: Send blood tubes by Fed Ex, UPS, Federal Post Office or other carrier. Ice in the package is NOT needed. Tubes must be sealed and packed well to prevent breakage. Samples can stay in shipment for up to 10 days without compromising the test. For obtaining timely results, a reliable carrier that delivers within one or two days is preferred. A form to submit sample can be obtained on the BioTracking web site or by Fax. ACCURACY OF THE BLOOD TEST TABLE: Accuracy of the PSPB blood test for pregnancy compared to examination of the uterus at slaughter. The 378 cows were bred between 26 and 61 days before uteri and blood were collected at slaughter. _________________________________________________________________________ UTERINE EXAM PSPB BLOOD TEST % OF STATUS NUMBER NUMBER UTERINE _________________________________________________________________________________________________________ NON-PREGNANT 187 177 95 PREGNANT 191 189 99 OVERALL TOTAL 378 366 97 ____________________________________________________________ From Mauer et al., 1985 *In the above study we examined the uteri of 378 cows (that were at least seven months postpartum) after slaughter and compared the results from visual observation of the uterus or uterine flushings with the blood test for pregnancy. Cows had been bred from 26 to 61 days before slaughter. The test was 99% correct in detection of pregnancy and 95 % correct in detection of non-pregnancy. This table shows that the test is extremely accurate in detection of pregnancy in cows. We have since shown that the test is highly accurate at 30 days after breeding in lactating cows and at 28 days in heifers (Humblot, et al., 1988). WORKSHEET COMPARE YOUR PALPATION TO BLOOD TEST COSTS PER COW FOR EACH STEP TO PREGNANCY DETECTION* 50 SAMPLES/TWO WEEKS (1313/Yr) Blood Estimated Cost Palpation Estimate Test Rectal Palpation Differential Your Costs/Cow 1. PROFESSIONAL TRAVEL 0.00 $ 1.20 +1.20 $_____/ _____hr, _____ trips ______ $60/1hr, 1trip, 1 hr 2. SAMPLE or PALPATE 0.33 3.00 +2.67 $_____/hr, one cow/1.5min ______ $20/hr, 1 sample/1 min $120/hr, 1 cow/1.5min 3. SUPPLIES & SHIPPING 0.50 0.10 gloves, lube, - 0.40 4. CORRAL RECORDER 0.00 0.50 +0.50 $_____/hr, one cow/1.5min ______ $20/hr, 1 cow/1.5min 5. EMBRYO DEATH COST 0.00 0.83** +0.83 ______ 6. TEST INACCURACY COST 0.00 2.00*** +2.00 Give value to you ______ 7. LAB ANALYSIS 2.10 to 5.00**** 0.00 - 2.10 to 5.00**** 8. RECORD IN COMPUTER 0.01 0.16 +0.15 $_____/hr, ____ min ______ $20/hr, 0.5 min TOTAL $2.94 to $5.84 $ 7.79 $4.85 to $1.95 ______ Blood Test Palpation Difference Your Total _______________________________________________________________________________________________________________________ * EXPENSES CONSIDERED THE SAME FOR BOTH TESTS ARE ANIMAL IDENTIFICATION, CATCHING ANIMALS, AND MANAGER ANALYSIS OF DATA * * CALCULATED AT 2.2% (the minimum) LOSS PER EMBRYO TOUCHED (ie. 38 embryos per 50 palpated) X $2.50/DAY FOR 20 DAYS *** EXAMPLE: EXPENSE OF FOLLOW-UP TREATMENT WITH PROSTAGLANDINS (LUTALYSE OR ESTRUMATE) OF THOSE DETERMINED NOT PREGNANT IN ERROR AND RESULTING IN EMBRYO DEATH **** TO BE DETERMINED BY CONTRACT WORKSHEET ITEMS 2 AND 3 EXPENSES FOR BLOOD SAMPLE COLLECTION ON A 1000 COW DAIRY NUMBER TESTED/YEAR 25% TESTED TWO TIMES; 6.25% TESTED THREE TIMES 1313 NUMBER TESTED AT 2 WEEK INTERVALS 50 LABOR (Worksheet Item 2) Number of Cows = 50/2 wks Bleed 1 cow/minute = 50 minutes/2 wks Wages ($20/hr) @ $ .33/min X 50 min = $ 16.50/2 wks Wages cost per sample = $16.50/50 = $ .33 SUPPLIES and SHIPPING (Worksheet Item 3) Vacutainer tubes (red topped) $ .15 Vacutainer needles, 18 G, 1 inch .15 Shipping, (50 samples) .20 TOTAL $ .83 WORKSHEET ITEM 5 PALPATION-EMBRYO-DEATH VALUE LOST DAYS 1. Cow conceives at 60 days postpartum 60 60 2. If aborted when palpated at 30 to 45 days after breeding 30 To 45 3. Cow conceives again 20 to 45 days later 20 To 45 TOTAL DAYS POSTPARTUM 110 To 150 4. A break-point at 90 days postpartum if open -90 -90 5. For each day open beyond 90 postpartum, it costs from $2.50 to $7.50 per day in lost milk and calves. Days open past 90 20 To 60 6. Cost for One Aborted Embryo Applies to Worksheet Item 5 (See next page) Value Lost* Cost at $2.50 /day, 20 to 60 days $ 50 To $ 150.00 Cost at $7.50 /day, 20 to 60 days $150 To $450.00 (per lactation: loss in milk and timely calf production) * Value does not include cost of semen, drugs or extra labor WORKSHEET ITEM 5 (Cont'd) PALPATION EMBRYO DEATH VALUE LOST HERD BASIS COST/ 1000 COWS In 1000 cows, if 75% are pregnant, 750 embryos are touched (palpated at 30 to 45 days after breeding at 60 days postpartum) TOUCHING- EMBRO-LOSS (of 750) DAYS LOST BEYOND 90 POST- PARTUM DOLLAR COST PER DAY % Number $2.50 $7.50 2.2 16.5 20 each 60 each $ 825* 2,475 $ 2,475 7,425 8.0 60 20 each 60 each $ 3,000 9,000 $ 9,000 27,000 Abbitt et al., 1978 and Alexander et al. 1995 for % embryo loss due to palpation * $825 divided by 1000 cows that are palpated equals: $ .83 per cow Apply this value to Worksheet at Item 5 This table shows that $ .83 is the minimum loss per palpation and that it can reach as high as $ 27 per palpation. Breeders are encouraged to substitute their own estimate to obtain a value for themselves. WORKSHEET ITEM 6 BLOOD TEST COMPARED TO RECTAL PALPATION Rectal Palpation: Vs. Blood Test by PSPB Pregnant (MISSED 9.3%) More Accurate Non-pregnant Equal Accuracy It depends upon the dairy as to how this can affect expenses. One example is in the use of Lutalyse to initiate a new cycle. Expense of such errors are shown below and on the next pages. Table : Accuracy of rectal palpation when the PSPB blood test and palpation was used to determine pregnancy between 30 to 45 days after AI. Pregnancy was confirmed by a second palpation and blood test at 60 days after AI. ___________________________________________________________ Not Detected No. Days Number Pregnant by Palpation* After Breeding Pregnant Number % 30 to 35 125 17 13.6 36 to 39 126 15 11.9 40 to 45 167 7 4.2 Overall 30 to 45 418 39 9.3 Alexander et al., 1995. Theriogenology 43:551-556. *The experiment was done in south central Washington with heifers in a commercial herd that bred 200 heifers per month. Heifers were synchronized to heat with prostaglandins. The person doing the palpation had several years experience in palpation for pregnancy within this size of herd and had more experience than most in the region. He also palpated the lactating herd. WORKSHEET ITEM 6 (Cont'd) Lutalyse Error Expense of Treatment Error 100 Head per Palpation Event Lutalyse is a prostaglandin drug that is used to induce heat in non-pregnant animals. Single and two-dose treatment regimes are available for timed insemination of cows and heifers. If Lutalyse is given to a cow early in pregnancy she will abort. Often Lutalyse is given to cows and heifers to induce an early heat when they are determined by palpation to be not pregnant. If the diagnosis is incorrect and the cow is pregnant, she will abort from the treatment. Per 100 head that are palpated it is expected that 75% are pregnant and 25% are not pregnant. Of the 75% that are pregnant, rectal palpation will miss from 5% to 9% and categorize them as NOT PREGNANT while they are actually pregnant. In 75 head this will be from 3.75 to 6.75 cows. If the management practice is to induce early estrus with Lutalyse following palpation then 4 to 7 cows will be aborted. This abortion is not discernable by clinicians or management without proper analysis. Until the clinician determines accuracy of palpation the exact loss cannot be certain. However, the best palpator will make errors when testing at 30 to 45 days after conception. A very, very experienced palpator missed 9% of heifers tested by palpation between 30 and 45 days after conception. This was confirmed by follow-up PSPB blood test and palpation at 60 days after conception (Alexander et al., 1995). It will take 20 days to reestablish pregnancy at $2.50 to $7.50 per day per cow. The total loss for aborting one cow is: Loss in calf and milk production per lactation: From: 20 days X $2.50 = $ 50 To: 20 days X $7.50 = $ 150 Total loss per 100 cows palpated: There are 5% to 9% of the cows that are pregnant and are called not pregnant in error. This is 4 to 7 cows per 100 palpated cows. Multiply The $ 50 to $ 150 in total loss per cow by 4 to 7 cows of the 100 palpated: A. $ 50 X 4 = $ 200 B. X 7 = $ 350 C. $150 X 4 = $ 600 D. X 7 = $1050 This extra hidden expense distributed over the whole 100 cows that were palpated is: From $ 200/100 = $ 2.00 each palpation (TO WORKSHEET ITEM 6) To $ 1050/100 = $ 10.50 each palpation Why risk these losses? It is more prudent to avoid these losses by using the non- invasive blood test. In summary, if clinicians induce early heat with Lutalyse treatment the hidden expense from palpating 100 cows can be added to other expenses of a) induced palpation abortions (another hidden cost), b) palpation labor c) professional travel expense and d) supplies. ACCURACY OF THE BLOOD TEST COMPARED TO OTHER PREGNANCY TESTS A. Ultrasonography Vs. Blood Test by PSPB Pregnant Animals: Equal Accuracy Non-pregnant Animals: More Accurate B. Progesterone in milk Vs. Blood Test by PSPB at 21 days after AI & blood test at 30 days Pregnant Animals: Less than 80% correct More accurate Non-pregnant Animals: Almost 100% correct Equal Accuracy SUMMARY Dairy managers are encouraged to assign pregnancy testing to BioTracking. It is possible for professionals who visit the dairy periodically or who are employed by the dairy to spend their valuable time with other important duties. Blood sampling for pregnancy testing can be assigned to other staff of the dairy at a lessor cost. In addition, data above show the importance of an accurate pregnancy test that does not touch and harm the embryo/fetus. Hidden costs which may not be apparent to managers or clinicians are realized when rectal palpation for pregnancy is practiced. Likewise, extreme care must be exercised when treating non-pregnant cows with drugs when one is not certain they are truly not pregnant. Managers may know of other expenses for not having an accurate test. A very high degree of certainty is obtained with the BioTracking blood test while scientific literature shows this is not the case with rectal palpation. Managers are asked to evaluate their expenses using the WORKSHEET in this document to determine the savings that are possible.