• TABLE OF CONTENTS
HIDE
 Title Page
 Preface
 Table of Contents
 Main
 Appendix














Group Title: Bulletin
Title: Liver flukes in Florida
CITATION DOWNLOADS THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00008438/00001
 Material Information
Title: Liver flukes in Florida prevalence, economics, and management practices on ranches surveyed
Series Title: Bulletin
Physical Description: 23 p. : map ; 28 cm.
Language: English
Creator: Simpson, James R
Courtney, Charles Hill, 1947-
Publisher: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida
Place of Publication: Gainesville Fla
Publication Date: 1990
 Subjects
Subject: Liver flukes -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
non-fiction   ( marcgt )
 Notes
Statement of Responsibility: James R. Simpson and Charles H. Courtney.
General Note: Cover title.
General Note: "June 1990."
 Record Information
Bibliographic ID: UF00008438
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: ltqf - AAA6703
ltuf - AHG0567
oclc - 22424910
alephbibnum - 001547029

Downloads
Table of Contents
    Title Page
        Title Page
    Preface
        Page i
    Table of Contents
        Page ii
        Page iii
    Main
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
    Appendix
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
Full Text


Bulletin 261


Liver Flukes in Florida:
Prevalence, economics, and management
practices on ranches surveyed


James R. Simpson and Charles H. Courtney


















Florida Cooperative Extension Service
Institute of Food and Agricultural Sciences
University of Florida
John T. Woeste, Dean


June 1990





















Preface


This bulletin is the product of a survey on liver
flukes (Fasciola hepatica) carried out through a do-
nation from MSDAGVET provided in 1984. The pro-
ject, and this bulletin, have been divided into several
parts: (1) fluke information from a five-county survey
in south and central Florida, (2) condemnation rates
due to liver flukes on cattle slaughtered at the
Kaplan Industries, Inc. slaughter plant over a five-
month period, (3) a survey of producers in North
Florida, (4) an economic analysis and, (5) manage-
ment information about ranch production practices
derived from the five county-survey.
The producer surveys resulted in considerable
management-related information. The results are
similar to those derived from other surveys (e.g.
IFAS, N.D.a; IFAS, N.D.b). Overall, it is concluded
that a substantial portion of Florida cattle south of
the Suwannee River are infested with flukes. There
is a relatively low prevalence rate west and north of
the Suwannee River. Producers who suspect their
cattle have liver flukes should have a test conducted
and treat if found, as there is a definite economic
advantage to treatment.








Contents

Page
Preface ................................. .................... ... .... ..................
List of Maps and Tables .................................................................... iii
Five-County Survey ................................................................... ... . 1
Five-County Survey, Fluke Information ..................................................... 4
Prevalence ...................... ........................................... ......... 4
Cost of Flukes ................................................................... ..... 4
Number of Fluke Treatments Annually ................. ..................................... 4
Fluke Treatment Seasons .............................................................. 4
Liver Fluke Treatment Conditions ......................................................... 4
Fluke Treatment Dose ....................................... .......................... 4
Kaplan Slaughter Plant Survey ............................................................. 4
North Florida Auction Market Survey .......................................................... 9
Economic Analysis and Discussion of Results ................................................ 11
Death Loss ............................................ 11
Average Weight of Cull Cows ..................................... ...................... 12
Reproductive Losses ............................................................... 12
Economic Analysis ......................................... ......................... 13
References .................................................................... .......... 13
Appendix: Tables, Five-County Survey, Management Information:
1 Breeding season, five-county Florida survey, 1984 ................ ......................... 15
2 Summary of breeding season, five-county Florida survey, 1984 ................................. 16
3 Age of cull cows at sale, five-county Florida survey, 1984 ................ ................... 16
4 Sale weight of cull cows, five-county Florida survey, 1984 ..................................... 17
5 Cow death losses, five-county Florida survey, 1984 ................. ....................... 18
6 Calf crop on a calves-born-and-weaned basis, five-county Florida survey, 1984 .................... 19
7 Usual nutritional level of cattle in winter, five-county Florida survey, 1984 ......................... 20
8 Replacement heifer death loss, five-county Florida survey, 1984 ................................ 20
9 Age at sale of steer calves, five-county Florida survey, 1984 .................................. 21
10 Age at sale of heifer calves, five-county Florida survey, 1984 ................................. 22
11 Sale weight of steer calves, five-county Florida survey, 1984 ................................. . 23
12 Sale weight of heifer calves, five-county Florida survey, 1984 ...... ............................ 24








Maps and Tables


Page
1 Questionnaires mailed and response rate, five-county liver fluke survey in Florida, 1984 .............. 1
Map 1: Counties included in five-county liver fluke survey, 1984 ................................ 2
2 Total farms responding to liver fluke survey by farm size per brood cow category and by
county, Florida, 1984 ................ . .................. ........................ .... 3
3 Proportion of ranch and brood cow population covered by five-county liver fluke
survey, Florida, 1984 .................................................................. 3
4 Liver fluke prevalence, five-county Florida survey, 1984 ................. ................... . 5
5 Liver fluke prevalence by ranch size, five-county Florida survey, 1984 ............................. 5
6 Costliness of liver flukes, five-county Florida survey, 1984 ...................................... 5
7 Costliness of flukes according to producer estimates of fluke prevalence, five-county
Florida survey, 1984 ................................................................... 6
8 Number of treatments annually for liver flukes, five-county Florida survey, 1984 ..................... 6
9 Number of treatments annually for liver flukes according to producer estimates of
prevalence, five-county Florida survey, 1984 ................................................ 7
10 Summary of liver fluke treatments by season, five-county Florida survey, 1984 ...................... 7
11 Conditions under which cattle are treated for liver flukes, five-county Florida survey, 1984 ............. 8
12 Conditions under which cattle are treated for liver flukes by ranch size, five-county
Florida survey, 1984 ...................... ............................................ 8
13 Summary analysis of Kaplan Industries Inc. slaughter plant liver fluke survey, 1984 .................. 8
14 Prevalence of flukes in North Florida from 1985 survey ................ ....................... 9
Map 2: Counties in North Florida identified as having liver flukes ................................ 10
15 Results of sampling for liver flukes and questionnaire at North Florida auctions, 1985 ............... 10
16 Average death loss of brood cows according to treatment for flukes, all ranches,
five-county Florida survey, 1984 ........................................................ 11
17 Average weight of cull cows according to treatment for flukes, all ranches,
five-county Florida survey, 1984 ................................. .... .................... 12
18 Calving percentage according to estimates of having flukes and treatment for
flukes, all ranches, five-county Florida survey, 1984 ................ ....................... 13
19 Economic advantage of treating for liver flukes ................ ............................ 14









LIVER FLUKES IN FLORIDA:
PREVALENCE, ECONOMICS, AND MANAGEMENT PRACTICES ON RANCHES SURVEYED
James R. Simpson and Charles H. Courtney*


Liver fluke infection is one of the most important
cattle health problems in Florida, as well as lower
Louisiana and East Texas, and selected areas of the
northwestern United States. It is also a major prob-
lem in many areas of the world. Producers are af-
fected by the need for early culling of cows, reduced
culling weights, lowered reproductive performance
and reduced calf weaning rates. They are also indi-
rectly harmed due to liver condemnations.
The occurrence of liver fluke infestation is limited
by distribution of its snail intermediate host. Wet
pastures favor the growth and reproduction of the
snails, which become infected by fluke eggs shed in
cow manure. After about 6-8 weeks development,
infectious forms are shed by the snail and encyst on
vegetation. These cysts are somewhat resistant to
environmental extremes and may survive several
months on pasture. The cycle is completed when the
cysts are ingested by grazing cattle, migrate to the
liver, and after maturity for 8-10 weeks begin to lay
eggs.

Five-County Survey

A one-page questionnaire with 19 questions was
distributed by county extension agents in five central
and southern Florida counties: Brevard, De Soto,
Hendry, Osceola, and Polk (Map 1). A total of 1,505
questionnaires were mailed out while 231 responses
or 15 percent were returned (Table 1). This response
rate included a second mailout. The return included
36 responses (16 percent of the 231) from question-
naires which were distributed to producers who de-
livered cattle directly to Kaplan Industries, Inc.
slaughter plant during that phase of this research
project or who have operations in more than one
county.
A total of 164,222 brood cows were recorded from
the 184 production units which provided information
on their inventory (Table 2). Because only 184 units
of the 231 responses replied to the question on inven-
tory, more cows are included in most of the question-
naire results than indicated. Thirty-eight percent of
the responses were operations with less than 50 head


of brood cows, 42 percent had 50-499 head (medium
ranches), and 20 percent had 500 head or more (large
ranches).
Another way to describe the survey respondents
is by number of head in each production unit cate-
gory. There were a total of 1,555 head or one percent
of the cows included in the inventory responses on
small ranches, 8 percent on medium ranches, and
91 percent on large ranches (Table 2).
The survey responses can also be evaluated by the
proportion of total farms and inventory covered by
the survey. The responses represent six percent of
all small ranches in the five counties surveyed, 14
percent of all medium ranches, and 30 percent of all
large ranches (Table 3). Again, these percentages
slightly underestimate the survey's magnitude since
only 184 of the 231 replies reported inventory.
The survey responses represent 45 percent of the
total beef cow inventory in the five-county area
(Table 3). State-wide cattle numbers decreased ap-
proximately 5 percent during the period 1982-1984.
Thus, these survey percentages are likely under-
stated since the census data are for 1982 while the
survey was completed at the end of 1984. The ques-
tionnaire response represents about 11 percent of
the state's entire beef cow inventory. The response
rate varied from a high of 78 percent of the beef cows
in Brevard county, to 12 percent of them in De Soto
county.

Table 1. Questionnaires mailed and response rate,
five-county liver fluke survey in Florida,
1984.

Responses
Questionnaires mailed Percent of all
County Number Percent Number responses

Brevard 100 6 15 6
De Soto 300 20 23 10
Hendry 275 18 13 6
Osceola 230 15 45 19
Polk 600 40 99 43
Others 36 16
Total 1,505 100 231 100


* Respectively, Professor and Extension Livestock Marketing Economist, Food and Resource Economics Department; and Associate
Professor, Department of Infectious Diseases; College of Veterinary Medicine; Institute of Food and Agricultural Sciences (IFAS),
University of Florida, Gainesville, FL 32611.























Map 1. Counties included in five-county liver fluke
survey, 1984.


C30004









Table 2. Total farms responding to liver fluke survey by farm size per brood cow category and by county,
Florida, 1984.

Average Number of farms by Number of brood cows by
Responses brood farm size category farm size category
Total indicating Total cows measured by number measured by number of
farms cow brood per of brood cows brood cowsd
County responding inventory cowsc farm 0-49 50-499 >500 0-49 50-499 >500
----- Farms----- ----- Head-----
Brevard 15 12 9,553 637 4 4 8 63 690 8,800
De Soto 23 17 5,741 250 9 6 2 172 969 4,600
Hendry 13 11 34,246 2,634 3 3 5 116 850 33,280
Osceola 45 38 63,943 1,421 13 11 14 273 1,640 62,030
Polk 99 77 9,912 100 33 42 2 822 6,902 2,188
Others 36 29 40,827 1,134 8 12 5 109 1,918 38,800
Total 231 184 164,222 711 70 78 36 1,555 12,969 149,698

-----------------------Percent----------------------
100 38 42 20 1 8 91
aIncludes Collier (1), Glades (1), Hillsborough (3), Lake (1), Lee (3), Manatee (3), No county name given (12),
Okeechobee (2), Sarasota (1), St. Lucie (2).
b 1,505 questionairres mailed out, response rate of 15 percent.
c Total for those responses indicating inventory.
dTotal for all three farm size categories is 164,222 head.


Table 3. Proportion of ranch and brood cow population covered by five-county liver fluke survey, Florida,
1984.

Proportion of ranches covered
Total ranches by herd size by survey, by herd size
500 and 500 and Brood cowsd
County 0-49 50-499 more Total 0-49 50-499 more Total Total respondents proportion
Brevard 111 29 11 151 4 14 73 8 12,237 9,553 78
DeSoto 199 115 24 338 5 5 8 5 46,945 5,741 12
Hendry 82 70 24 176 4 4 21 6 73,584 34,246 47
Osceola 158 95 24 277 8 12 58 14 83,209 63,943 77
Polk 604 267 36 907 5 16 6 8 58,173 9,912 17
Others -
Totalb 1,154 576 119 1,849 6 14 30 10 274,148 123,395 45
Total
FL 1,098,152 11
aSource: 1982 Census of Agriculture.
bThere are responses from other counties (Tables 1 and 2) but these are not included in this table.
c Responses (Table 2) divided by population, this table.
dCategory beef cows from the 1982 Census of Agriculture. DeSoto county does not have an entry so the
category "cows and heifers" is used.








Five-County Survey, Fluke Information

Prevalence
Thirty-four percent of the 231 producers respond-
ing to the question, "do you have flukes on your prop-
erty?" answered "yes". Twenty-four percent said "no",
and 42 percent indicated they did not know (Table
4). The highest proportion of the "yes" answers (85
percent) was in Hendry county while the lowest pro-
portion (23 percent) was in Osceola county.
Another way to evaluate the estimates of prev-
alence is according to responses by size of ranch.
Table 5 shows that nearly two-thirds of the small
producers (61 percent) i.e. those with less than 50
head, did not know if they had flukes, while that
estimate was 44 percent for all producers. Thirty-four
percent of all respondents believed they had flukes,
while the estimate was just 13 percent for the smaller
dnes.

Cost of Flukes
All survey respondents (231) replied to the ques-
tion about cost of flukes. Thirty percent believed
them to be costly, 49 percent said "no", and 21 percent
replied they did not know (Table 6). Hendry county
had the greatest proportion of fluke-infested ranches
among all five counties surveyed. It also had the
greatest response to flukes being costly. However,
this response is somewhat confounded by the greater
prevalence of large ranches in this county.
Among the respondents who replied "yes, they did
have flukes", there was almost the same proportion
of replies to "yes, flukes are costly", among both small
producers and all respondents (78 and 77 percent
respectively) (Table 7). The response was exactly the
same (89 percent) among small and all producers
who replied "no, they did not have flukes", and "no,
they are not costly."

Number of Fluke Treatments Annually
Fifty-six percent of the 231 producers responding
said they do not treat for flukes, 31 percent treat
once a year, 11 percent treat twice annually, and 2
percent three times. Only one producer of the 231
respondents indicated treatment four times annually
(Table 8). Hendry county producers not only per-
ceived flukes to be costly, but also treated to a much
greater extent than in other counties.
Treatments have been broken down in Table 9 ac-
cording to estimates of fluke prevalence. Sixty-seven
percent of small producers who estimated they have
flukes treated once as opposed to 61 percent of all
respondents. Among those who didn't know if they


have flukes, 75 percent of all small producers didn't
treat at all, which was about the same (80 percent)
for all producers.

Fluke Treatment Seasons
There was a wide variety of treatment times ac-
cording to the survey results. However, forty-two
percent of the 106 producers responding stated they
only treated in the spring (January-June) while 31
percent treated only in the fall (Table 10). Sixteen
percent treated in both the spring and fall. Four per-
cent treated all year while two percent treated in
the spring and summer, and another two percent
treated in the summer and fall. Three percent treated
in the summer only. Overall, 49 percent treated at
least once in the fall, which is considered by Univer-
sity of Florida veterinarians the optimal treatment
season.

Liver Fluke Treatment Conditions
There were a total of 110 respondents to the ques-
tion about conditions under which cattle were treated
for flukes. Fifty-seven percent of ranchers indicated
they treated for flukes when they treated for other
parasites, 34 percent when cattle were worked for
other reasons, and 9 percent by special roundup
(Table 11).
Seventy-five percent of small producers indicated
they treated when cattle were treated for other para-
sites, compared with 57 percent for all respondents
(Table 12). About one-third of all respondents treated
when cattle were worked for other reasons as opposed
to 11 percent of small producers.

Fluke Treatment Dose
Eighty-nine percent of the 99 respondents indi-
cated they treated their cattle according to label in-
structions. Ten percent used a little more than the
recommended dose while one percent used a little
less than the label instructions. There was no signif-
icant difference between counties.

Kaplan Slaughter Plant Survey

An agreement was reached with Kaplan Indus-
tries, Inc. for their slaughter plant at Bartow,
Florida, to maintain records on all livers inspected
on mature cattle slaughtered from August 15, 1984,
through December 31, 1984. There were a total of
432 lots of cattle comprising 25,238 head. Of those,
16,207 head or 64 percent had livers condemned due
to flukes (Table 13). There were 9 percent which had
livers condemned for other reasons, making a 73 per-
cent total condemnation rate.








Table 4. Liver fluke prevalence, five-county Florida survey, 1984.

Have County
Flukes Brevard DeSoto Hendry Osceola Polk Others Total

-------------------------------Ranches-------------------------------
Yes 7 8 11 11 23 18 78
No 3 6 1 18 23 4 55
Don't know 5 9 1 17 53 13 98
Total 15 23 13 45 99 35 231

-------------------------------Percent-------------------------------
Yes 47 35 85 23 51 51 34
No 20 26 7 40 23 11 24
Dont'know 33 39 8 37 54 38 42
Total 100 100 100 100 100 100 100



Table 5. Liver fluke prevalence by ranch size, five-county Florida survey, 1984a.

Ranch size Percent Small as a
Prevalence Small Large All Small Large All percent of total

Yes 9 69 78 13 43 34 12
No 18 37 55 26 23 24 32
Don'tknow 43 55 98 61 34 42 44
Total 70 161 231 100 100 100 30
aNo significant difference between size categories p = 0.99


Table 6. Costliness of liver flukes, five-county Florida survey, 1984.

County
Items Brevard DeSoto Hendry Osceola Polk Others Total
------------------ ------------ Ranches-------------------------------
Yes 7 4 10 8 27 14 70
No 7 14 1 28 49 14 113
Don'tknow 1 5 2 9 23 8 48
Total 15 23 13 45 99 36 231

------------------------------P ercent-------------------------------
Yes 47 17 77 18 27 39 30
No 47 61 8 62 50 39 49
Don'tknow 6 22 15 20 23 22 21
Total 100 100 100 100 100 100 100








Table 7. Costliness of flukes according to producer estimates of fluke prevalence,
survey, 1984.


five-county Florida


Ranch size Percent Small as a
Costliness Small All Small All percent of total

Don't know if they have flukes
Yes 1 6 2 6 17
No 19 51 44 52 37
Don't know 23 41 53 42 56
Subtotal 43 98 100 100 44

Yes, they do have flukes
Yes 7 60 78 77 12
No 1 13 11 17 8
Don't know 1 5 11 6 20
Subtotal 9 78 100 100 12

No, they don't have flukes
Yes 2 4 11 7 50
No 16 49 89 89 33
Don't know 0 2 0 4 0
Subtotal 18 55 100 100 33

Total
Yes 10 70 14 30 14
No 36 113 52 49 32
Don'tknow 24 48 34 21 50
Total 70 231 100 100 30



Table 8. Number of treatments annually for liver flukes, five-county Florida survey, 1984.

Annual County
treatments Brevard DeSoto Hendry Osceola Polk Others Total

-----------------------------Ranches-----------------------------
0 5 13 3 27 64 17 129
1 6 5 7 15 27 12 72
2 2 5 2 3 8 5 25
3 2 0 1 0 0 1 4
4 0 0 0 0 0 1 1
Total 15 23 13 45 99 36 231

----------------------------- Percent-----------------------------
0 34 56 23 60 65 47 56
1 40 22 54 33 27 33 31
2 13 22 15 7 8 14 11
3 13 0 8 0 0 3 2
4 0 0 0 0 0 3 0
Total 100 100 100 100 100 100 100








Table 9. Number of treatments annually for liver flukes according to producer estimates of prevalence, five-
county Florida survey, 1984.

Number of Ranch size Percent Small as a
Treatments Small All Small All percent of total


Don't know if they have flukes
78 75


2
0
100


0
1
2
3
4
Subtotal


0
1
2
3
4
Subtotal


0
1
2
3
4
Subtotal


Table 10. Summary of liver fluke treatments by season, five-county Florida survey, 1984.

Season Percent Months

Spring 42 January-June only
Summer 3 July-August only
Fall 31 September-December only
Spring, Summer 2 January-June and July-August
Summer, Fall 2 July-August and September-December
Spring, Fall 16 January-June and September-December
All Year 4 Jannuary-December


32
7
3
1
0
43


Yes, they do have flukes
9 22
48 67
17 11
3 0
1 0
78 100

No, they don't have flukes
42 67
10 28
3 5
0 0
0 0
55 100

Total
129 66
72 26
25 7
4 1
1 0
231 100


80
14
5
1
0
100


12
61
22
4
1
100


76
18
6
0
0
100


56
31
11
2
0
100


0
1
2
3
4
Total








Table 11. Conditions under which cattle are treated for liver flukes, five-county Florida survey, 1984.

County
Conditions Brevard DeSoto Hendry Osceola Polk Others Total
---------------------------- Ranches---------------------------
When treated for
other parasites 4 7 6 14 23 9 63
When worked for
other reasons 6 5 2 4 11 9 37
By special roundup 0 0 1 1 6 2 10
Total 10 12 9 19 40 20 110

-----------------------------Percent---------------------------
When treated for
other parasites 40 58 67 74 58 45 57
When worked for
other reasons 60 42 22 21 27 45 34
By special roundtrip 0 0 11 5 15 10 9
Total 100 100 100 100 100 100 100


Table 12. Conditions under which cattle are treated for liver flukes by ranch size, five-county Florida survey,
1984a.

Ranch size Percent Small as a
Condition Small Large All Small Large All percent of total
----- Ranches -----
When treated for
other parasites 21 42 63 75 51 57 33
When worked for
other reasons 3 34 37 11 41 34 8
By special roundup 4 6 10 14 7 9 40
Total 28 82 110 100 99 100 -
aNo significant difference between size categories, p = 0.99-0.01 level.


Table 13. Summary analysis of Kaplan Industries Inc. slaughter plant liver fluke survey, 1984.

Slaughtered Condemnation for flukes
Class of Cattle Number Proportion Number Proportion
-Head- -Percent- -Head- -Percent-
Beef breed cows 9,924 39 6,727 68
Beefbreed steers 244 1 137 56
Heifers 57 0 24 42
Bulls 544 2 391 72
Dairy Cows 945 4 560 59
Subtotal 11,714 46 7,839 70
Mixed 13,524 54 8,368 62
Total 25,238 100 16,207 64








An analysis of the data by class of cattle reveals
the highest proportion of fluke condemnations, 72
percent, was from bulls (Table 13). The next largest
proportion was beef breed cows (68 percent) with the
third largest group being dairy cows (59 percent).
Beef breed steers had a 56 percent condemnation
rate while 42 percent of heifers were condemned.
About half the lots (54 percent of all cattle) were
made up of several classes. These mixed lots had a
62 percent condemnation rate. A chi square analysis
indicated there was a significant difference between
the condemnation rate for beef cows and all other
classes of cattle.
Examination of livestock source indicates that the
vast majority of cattle slaughtered (probably 90 per-
cent or more) were from central or southern Florida.

North Florida Auction Market Survey

Review of the survey results from Kaplan's slaugh-
ter plant indicated that a fluke prevalence might
exist in northern Florida. Consequently, a survey
was carried out to confirm the proposal. The ap-
proach taken was to have one laboratory technician
collect manure samples and fill out a survey form at
four North Florida auction markets for a five-week
period during July and August, 1985. The manure
samples were subsequently examined for the pres-
ence of fluke eggs. The technician attended a total
of 13 market days over the period at the Gainesville,
Lake City, Chipley and Graceville auction markets.


Producers bringing mature cattle to market were
approached by the technician who requested permis-
sion to collect manure samples. There was only one
refusal. Two to three samples were collected per
transport unit. The same survey form used in the
five-county southern Florida survey was completed
by direct interview.
A total of 225 transport units was surveyed (includ-
ing 20 from Georgia and Alabama) of which 9 were
positive for the relatively harmless rumen fluke, 1
for the true liver flukes (fasciola) and 5 for both (Table
14). Ranches and farms infected with liver flukes
were located in only five of the 27 counties from which
cattle originated: Flagler, Okalusa, Seminole,
Suwannee, and Washington (Map 2).
One of the survey questions involved producer es-
timation of whether he/she thought flukes were
present on his/her farm. There were only two produc-
ers (1 percent of the sample) who believed they had
flukes while 106 (or 47 percent) of the respondents
indicated they didn't know (Table 15). Twenty per-
cent felt they did not have flukes. One of the two
producers who believed liver flukes were present
tested positive while the other was negative. There
were only nine producers who treated for flukes, two
each in Columbia and Holmes counties, and one each
in Flagler, Levy, Hamilton, Putnam, and Suwannee
counties. The technician and a county agent visited
7 farms suspected of having flukes in August in
Union and Columbia counties and collected samples.
None of the samples tested positive.


Table 14. Prevalence of flukes in north Florida from 1985 survey.

Positive for
Farms Paramphistomes Fasicola
County tested (rumen flukes) (liver flukes) Both
-number-
Alachua 19 1 -
Bradford 4 1 -
Columbia 17 1 -
Flagler 1
Gadsden 1 1 -
Jackson 17 1 -
Okalusa -1 -
Putnam 5 1 -
Seminole -- 1
Suwanee 22 2 2
Washington 18 1 1
Subtotal 103 9 1 5
Others 122 -
Total 225 9 1 5



























Map 2. Counties in North Florida identified as
having liver flukes.


Table 15. Results of sampling for liver flukes and
questionnaire at North Florida auctions,
1985.

Producer estimation Response
of fluke prevalence Number Percent

Yes 2 1
No 44 20
Don't know 106 47
Not answered 73 32
Total 225 100


dO
CD~








Economic Analysis and Discussion
of Results

A previous economic analysis on liver flukes
(Simpson, Kunkle, Courtney, and Shearer, 1985) es-
timated that financial benefits to producers from
fluke control are derived from reduced death, weight
and productive loss in cows and replacement heifers
as well as reduced calf sale weight. However, at the
time of the analysis published data were scanty, and
consequently estimates were largely based on opin-
ions of veterinarians associated with the disease. The
purpose of this section is to compare and contrast
data and results from the previous study with data
generated by the surveys, and to include new infor-
mation from the author's study. Information in addi-
tion to that presented in the text and associated
tables is provided in Appendix.


Death Loss
The average death loss for producers in the five-
county survey area (the five counties described in
the first section of this report) who treated for flukes,
and also estimated they do have flukes, was 1.51
percent (Table 16). In contrast, the death loss re-
ported was 1.05 percent for those who didn't treat
(6 producers). These results may be biased by the
small number of those who didn't treat, only repre-
senting 10 percent of the cattle. Perhaps more impor-
tant were the group who indicated they didn't know,
in which the average death loss was 0.90 for those
who treat versus 1.65 for those who didn't treat. The
number of producers by size category was too small
to permit statistical analysis by category. Thus, no
conclusions can be drawn concerning the effect of
flukes on cattle mortality.


Table 16. Average death loss of brood cows according to treatment for flukes, all ranches, five-county
Florida survey, 1984.

Total cow Total death Average
Treatment Ranches inventory loss death loss

-Number- -----------Head----------- -Percent-
Don't know if they have flukesa
Yes 20 2,455 22 0.90
No 54 4,001 66 1.65
Subtotal 74 6,456 88 1.36

Yes, they do have flukesb
Yes 59 135,027 2,035 1.51
No 6 15,315 161 1.05
Subtotal 65 150,342 2,196 1.46

No, they don't have flukesc
Yes 13 2,206 30 1.36
No 20 2,350 39 1.66
Subtotal 33 4,556 69 1.51

Totald
Yes 92 139,688 2,007 1.44
No 80 22,466 266 1.18
Total 172 162,152 2,352 1.45
aSignificant difference between yes and no, p = 0.015
bSignificant difference between yes and no, p = 0.00001
c No significant difference between yes and no.
dSignificant difference between yes and no, p = 0.014








Average Weight of Cull Cows
Analysis of all respondents shows that on average
those who did treat received a 40 lb. advantage over
those who did not treat (Table 17). However, these
totals, and the rest of those in this section on
economic analysis, are subject to misrepresentation
since they include some producers whose ranches
probably didn't have flukes. In addition albendazole,
which was the only flukicide available at the time of
the survey, was a potent nematocide and some of the
apparent albendazole benefit may be from its control
of stomach and intestinal worms. An attempt is made
to circumvent this problem by dividing the results
according to treatment.
Results from the aggregation of the 37 producers
who do treat, even though they don't know if they
have flukes, indicate they have a 37 lb. advantage
compared with those who do not treat. However,


Table 17. Average weight of cull cows according to
treatment for flukes, all ranches, five-
county Florida survey, 19848.

Average Advantage
Treatment Ranches weight treatment
-Number- ----- Pounds -----
Don't know if they have flukes
Yes 8 878 37
No 29 841 -
Subtotal 37 849

Yes, they do have flukes
Yes 47 884 1
No 5 883 -
Subtotal 52 884

No, they don't have flukes
Yes 7 926 74
No 14 852 -
Subtotal 21 877

Total
Yes 62 888 40
No 48 848 -
Subtotal 110 871
a Significance levels between treated and non-treated
cannot be calculated due to not having individual
cow weights.


oddly enough, of the respondents who estimated they
do have flukes on their property, there was no differ-
ence between those who do treat (47) and those who
don't treat (5). In contrast, there was a 74 lb. advan-
tage to the 7 producers who treat even though they
feel flukes are not present on their ranches compared
with those 14 who say no, but don't treat. Thus, it
is not possible to arrive at a firm conclusion with
this data about cull cow weight differences.
Results from a recent survey conducted over a two
year period on a large central Florida ranch indicated
that on a whole herd basis cows treated for flukes
weighed 77 lbs. more per head than controls. Treated
cull cows averaged about 20 lbs. heavier than con-
trols (Simpson, Griner and Richey, 1989).
Overall, it appears that the range in weight loss
is probably from 30-50 lbs. per cow in the herd on
average, and that the low to high range could easily
be 20 to 60 lbs. The range for cull cows is likely 10-30
lbs.

Reproductive Losses
The measure for reproductive loss is reduced calf
crop. Overall, of the 176 respondents who replied to
the questions on treatment as well as provided esti-
mates of flukes, the 94 who replied "yes" they do
treat, had an average calf crop of 85 percent (Table
18). In contrast, those who do not treat had a 77
percent calf crop, i.e. 8 percent less.
Results from the two-year study on the central
Florida ranch mentioned earlier (Simpson, Griner
and Richey, 1989) indicated there was no statistical
difference in reproductive losses between the treated
and control groups. At this point, estimates of repro-
ductive losses are open to wide discussion. Given
that flukes do have a long-term debilitating effect,
an estimate of 1-3 percent is reasonable, but not sup-
ported by statistical evidence.
It was not possible to determine calf weight differ-
ences in treated versus non treated cows from the
survey. However, the central Florida study
(Simpson, Griner and Richey, 1989) indicated that
steer calves treated only for flukes averaged 44 lbs.
more than controls over the two-year period while
those treated for both flukes and parasites averaged
32 lbs. more than controls. The corresponding
weights were 31 and 26 lbs. for heifer calves. The
combined weighted average advantage (for steer and
heifer calves) was 39 lbs. Thus, while the results are
open to discussion, it is concluded that the appro-
priate range in weight advantage for calves from
treating is 30-45 lbs.








Economic Analysis
It is concluded that reasonable ranges for the ad-
vantage from treating includes 18-22 lb. heavier cull
cows, 1-3 percent more calves, and 30-45 lb heavier
calves weaned. These parameters are open to wide
discussion, but appear to be the best available esti-
mates.
A cost and returns budget, presented in Table 19,
indicates that if a producer had a 70 percent calf
crop and sold calves at an average of $0.60 per lb,
the net benefit from treating for flukes would be
$15.19 per cow unit (i.e. a total breeding cows in the
herd basis). If the calves were sold at $0.90 per lb
the net return would be $23.83 per cow unit. In effect,
as the value of livestock increases, there is more
incentive to treat. Another way to analyze fluke
treatment is that the risk from not treating increases
as output price increases. The net return increases
to $19.99 and $31.03 when the calf crop increases
from 70 to 90 percent for the two calf prices, respec-
tively.


References


IFAS, "Survey of Beef-Forage Production Practices:
Greater Tampa Bay Area, 1982 Summary," Florida
Cooperative Extension Service, PE2, n.d.a.

IFAS, "Survey of Beef-Forage Practices: South Cen-
tral Florida, 1986 Summary," Florida Cooperative
Extension Service, n.d.b.

Simpson, James R., William Kunkle, Charles
Courtney and Jan Shearer. "Economic Analysis of
Controlling Liver Flukes." Agri-Practice, Vol. 6, No.
2 (Feb.,1985):20-24.

Simpson, James R., Ellis C. Griner and Eddie J.
Richey. "It Costs, But It Pays to Control Liver Flukes,
Other Parasites." The Florida Cattleman June, 1989,
pp. 27-29.


Table 18. Calving percentage according to estimates of having flukes and treatment for flukes, all ranches,
five-county Florida survey, 1984.a

Average Weighted
calves average
Number Total Total per calving
Treatment ranches cows calves ranch percent
-Number- ---------------Head --------------- -Percent-
Don't know if they have flukes
Yes 23 3,100 2,563 111 83
No 54 5,189 4,074 75 79
Subtotal 77 8,289 6,637 86 80

Yes, they do have flukes
Yes 58 135,027 115,189 1,986 85
No 6 15,315 11,890 1,982 78
Subtotal 64 150,342 127,079 1,986 84

No, they don't have flukes
Yes 13 2,206 1,690 130 77
No 22 3,385 2,443 111 72
Subtotal 35 5,591 4,133 118 74

Total
Yes 94 140,333 119,441 1,271 85
No 82 23,889 18,407 224 77
Subtotal 176 164,222 137,848 783 84
a Significance level between treated and non-treated cannot be calculated due to not having individual cow data.








Table 19. Economic advantage of treating for liver flukes.

70 percent calf crop 90 percent calf crop
and calf price of: and calf price of:
Item Advantage 0.60 0.90 0.60 0.90
----------------- $ per cow unit-----------------
Cull cowsa 20 lbs/hd 0.56 0.80 0.56 0.80
Deathlossb 1 Pct 2.63 2.63 2.63 2.63
Heavier calves 40 lbs/hd 16.80 25.20 21.60 32.40
Total income 19.99 28.63 24.79 35.83
Expenses 4.80 4.80 4.80 4.80
Net 15.19 23.83 19.99 31.03
a$0.60 per lb for calves corresponds to $0.35 per lb for cull cows while $0.90 for calves corresponds to $0.50
for cull cows. The advantage would thus be $7.00 per cull cow sold when the calves sell for $0.60 per head.
Assume an 8 percent replacement rate, then the advantage is $0.56 per cow unit.
bAssume cows weigh 750 lbs. Then, the total value is $263 per head. A one percent death loss means there
is a loss of $263 for 100 cows so it is $2.63 per cow unit.
c 40 lbs per head and 70 percent calf crop is 28 lbs per cow unit @ $0.60 per Ib plus $16.80 per cow unit.
dGriner, Simpson and Richey, 1988.








Appendix: Tables, Five-County Survey, Management Information


The information in this appendix contains management information derived from the five-county survey.
In general, the results are similar to those found in surveys conducted in other parts of the state. The reader
is directed to them for specifics (IFAS, N.D.a; IFAS, N.D.b).


Appendix Table 1. Breeding season, five-county Florida survey, 1984.

Season Ranches Season Ranches


January-March
January-April
January-May
January-June
January-July
January-August
January-September
January-October
January-November


2
4
2
3
10
2
1
1
1


April-May
April-June
April-July
April-August
April-September
April-October
April-November


Subtotal


Subtotal


February-April
February-May
February-June
February-July
February-August
February-September
February-October


Subtotal


March-May
March-June
March-July
March-August
March-September
March-October
March-November
March-December


May-July
May-August

Subtotal

June-August
July-May
August-November
November-January
November-March

Subtotal


Subtotal


0
0
5
5
0
2
2








Appendix Table 2. Summary of breeding season, five-county Florida survey, 1984.

Season Number Percent

Spring only, four months or less 20 10
Spring only, five or six months 12 6
Spring and summer 50 26
Spring, Summer, Fall and Winterc 12 6
Summer and Falld 1 1
Fall only 0 0
Winter onlyf 2 1
Nine-eleven months 7 4
11year 89 46
Total 193 100
a January-June. d July-November.
b January-August. e September-November.
c Eight months or less. fNovember-March.


Appendix Table 3. Age of cull cows at sale, five-county Florida survey, 1984.

County
Age Brevard DeSoto Hendry Osceola Polk Others Total

-Years- ------------------------------Ranches -----------------------------
15 1 0 0 1 1 1 4
14 0 0 1 2 1 0 4
13 0 1 0 0 2 0 3
12 1 3 2 4 7 5 22
11 0 1 0 3 1 1 6
10 0 2 6 6 19 3 36
9 0 0 0 0 0 0 0
8 0 1 1 1 4 1 8
7 or less 14 14
Total 2 8 10 17 35 25 97

------------------------------- Percent ------------------------------
15 50 0 0 6 3 4 4
14 0 0 10 12 3 0 4
13 0 12 0 0 6 0 3
12 50 39 20 23 20 20 23
11 0 12 0 18 3 4 6
10 0 25 60 35 54 12 37
9 0 0 0 0 0 0 0
8 0 12 10 6 11 4 8
7orless 0 56 15
Total 100 100 100 100 100 100 100








Appendix Table 4. Sale weight of cull cows, five-county Florida survey, 1984.

Sale County
Weight Brevard DeSoto Hendry Osceola Polk Others Total
-Lbs- ------------------------------Ranches-----------------------------
950-999 4 3 6 6 10 3 32
900-949 0 2 1 8 11 9 31
850-899 1 0 1 3 5 0 10
800-849 0 2 2 8 4 2 18
750-799 0 0 0 0 4 2 6
700-749 0 1 1 1 4 2 9
650-699 0 1 0 0 0 0 1
600-649 0 0 0 0 3 0 3
Total 5 9 11 26 41 18 110

-------------------------------Percent------------------------------
950-999 80 34 55 23 24 17 29
900-949 0 22 9 31 27 50 28
850-899 20 0 9 12 12 0 9
800-849 0 22 18 31 10 11 16
750-799 0 0 0 0 10 11 5
700-749 0 11 9 3 10 11 9
650-699 0 11 0 0 0 0 1
600-649 0 0 0 0 7 0 3
Total 100 100 100 100 100 100 100








Appendix Table 5. Cow death losses, five-county Florida survey, 1984.

County
Loss Brevard DeSoto Hendry Osceola Polk Others Total

-Percent- ---.---------------------------Ranches ------------------------------
<1 3 6 2 16 26 9 62
1 2 5 8 9 23 8 55
2 6 4 1 9 14 3 37
3 1 1 0 1 11 4 18
4 1 1 0 0 2 1 5
5 0 0 0 0 1 1 2
6 0 0 0 0 0 1 1
7 0 0 0 0 0 0 0
8 1 0 0 0 0 0 1
9 0 0 0 0 0 0 0
10 1 0 0 0 1 0 2
Total 15 17 11 35 78 27 183

------------------------------- Percent------------------------------
<1 20 35 18 46 33 33 34
1 12 29 73 26 29 30 30
2 40 24 9 26 28 11 20
3 7 6 0 2 14 14 10
4 7 6 0 0 3 4 3
5 0 0 0 0 1 4 0
6 0 0 0 0 0 4 0
7 0 0 0 0 0 0 0
8 7 0 0 0 0 0 0
9 0 0 0 0 0 0 0
10 7 0 0 0 2 0 3
Total 100 100 100 100 100 100 100








Appendix Table 6. Calf crop on a calves-born-and-weaned basis, five-county Florida survey, 1984.

Born or
Weaning County
Percent Brevard DeSoto Hendry Osceola Polk Others Total
------------------------------Ranches------------------------------


Calves Born
18
11
5


Calves Weaned
11
9
5
1
1
27


88
58
24
6
4
180


65
54
27
5
4
155


-------------------------------Percent -----------------------------


Calves Born
50
30
14
3
3
100


Calves Weaned
40
33


0
100


4
100


52
30
13
5
0
100


46
32
16
6
0
100


56
30
10
4
0
100


38
46
12
0
4
100


49
32
14
3
2
100


90-99
80-89
70-79
60-69
50-59
Total


90-99
80-89
70-79
60-69
50-59
Total


50
36
14
0
0
100


38
38
6
0
18
100


90-99
80-89
70-79
60-69
50-59
Total


90-99
80-89
70-79
60-69
50-59
Total


0
100


13
100








Appendix Table 7. Usual nutritional level of cattle in winter, five-county Florida survey, 1984.

Nutritional County
Level Brevard DeSoto Hendry Osceola Polk Others Total

------------------------------ Ranches-----------------------------
High 5 10 2 10 39 18 84
Medium 7 10 9 30 55 16 127
Low 2 0 2 0 2 1 7
Total 14 20 13 40 96 35 218

------------------------------Percent -----------------------------
High 36 50 15 25 41 51 39
Medium 50 50 70 75 57 46 58
Low 14 0 15 0 2 3 3
Total 100 100 100 100 100 100 100



Appendix Table 8. Replacement heifer death loss, five-county Florida survey, 1984.

Death County
Loss Brevard DeSoto Hendry Osceola Polk Others Total

-Percent- ----------------------------- Ranches-----------------------------
0 11 10 7 25 66 23 142
1 1 4 4 6 9 4 28
2 1 2 0 2 1 0 6
3 0 0 0 1 1 0 2
4 0 0 0 0 1 0 1
Total 13 16 11 34 78 27 179

------------------------------Percent -----------------------------
0 85 63 64 74 85 85 79
1 8 25 36 18 12 15 16
2 7 12 0 6 1 3
3 0 0 0 2 1 1
4 0 0 0 0 1 1
Total 100 100 100 100 100 100 100








Appendix Table 9. Age at sale of steer calves, five-county Florida survey, 1984.

County
Age Brevard DeSoto Hendry Osceola Polk Others Total

-Months- ------------------------------Ranches ------------------------------
13 and more 0 0 0 0 0 1 1
12 1 2 0 1 5 0 9
11 0 0 0 1 0 1 2
10 0 1 0 1 5 2 9
9 0 2 1 3 2 2 10
8 3 0 5 7 12 6 33
7 1 4 1 5 8 3 22
6 1 2 0 0 9 2 14
5 0 0 0 2 2 0 4
4 0 0 0 0 3 0 3
Total 6 11 7 20 46 17 107

------------------------------Percent------------------------------
13 and more 0 0 0 0 0 6 1
12 17 18 0 5 11 0 8
11 0 0 0 5 0 6 2
10 0 10 0 5 11 12 8
9 0 18 14 15 4 12 9
8 50 0 72 35 26 35 31
7 17 36 14 25 17 17 21
6 16 18 0 0 20 12 13
5 0 0 0 10 4 0 4
4 0 0 0 0 7 0 3
Total 100 100 100 100 100 100 100








Appendix Table 10. Age at sale of heifer calves, five-county Florida survey, 1984.

County
Age Brevard DeSoto Hendry Osceola Polk Others Total
-Months- ------------------------------ Ranches ------------------------------
13 and more 0 0 0 0 0 7 7
12 0 1 0 1 5 0 7
11 0 0 0 1 0 1 2
10 0 2 0 1 3 2 8
9 0 0 1 5 2 4 12
8 3 0 5 6 10 6 30
7 1 4 1 5 8 1 20
6 0 3 0 2 9 0 14
5 0 0 0 0 2 0 2
4 0 0 0 0 2 0 2
Total 4 10 7 21 41 21 104

------------------------------ Percent------------------------------
13 and more 0 0 0 0 0 33 7
12 0 10 0 5 12 0 7
11 0 0 0 5 0 5 2
10 0 20 0 5 7 10 8
9 0 0 14 24 5 18 11
8 75 0 72 29 24 29 29
7 25 40 14 24 20 5 19
6 0 30 0 10 22 0 13
5 0 0 0 0 5 0 2
4 0 0 0 0 5 0 2
Total 100 100 100 100 100 100 100








Appendix Table 11. Sale weight of steer calves, five-county Florida survey, 1984.

Sale County
Weight Brevard DeSoto Hendry Osceola Polk Others Total

-Lbs.- ------------------------------Ranches ----------------------------
700-749 0 0 0 0 1 0 1
650-699 0 0 0 1 0 0 1
600-649 0 0 0 3 8 1 12
550-599 0 1 1 0 0 3 5
500-549 3 3 4 5 4 3 22
450-499 2 2 1 9 6 8 28
400-449 0 4 1 5 15 2 27
350-399 1 1 0 2 6 1 11
300-349 0 0 0 0 6 0 6
250-299 0 0 0 0 4 0 4
200-249 0 0 0 0 1 0 1
Total 6 11 7 25 51 18 118

------------------------------Percent------------------------------
700-749 0 0 0 0 2 0 1
650-699 0 0 0 4 0 0 1
600-649 0 0 0 12 16 6 10
550-599 0 9 14 0 0 17 4
500-549 50 27 58 20 8 17 19
450-499 33 18 14 36 12 43 24
400-449 0 37 14 20 28 11 23
350-399 17 9 0 8 12 6 9
300-349 0 0 0 0 12 0 5
250-299 0 0 0 0 8 0 3
200-249 0 0 0 0 2 0 1
Total 100 100 100 100 100 100 100








Appendix Table 12. Sale weight of heifer calves, five-county Florida survey, 1984.

Sale County
Weight Brevard DeSoto Hendry Osceola Polk Others Total

-Lbs.- ------------------------------Ranches -----------------------------
700-749 0 0 0 0 1 1 2
650-699 0 0 0 0 1 0 1
600-649 0 1 0 0 1 1 3
550-599 0 0 0 2 1 2 5
500-549 0 0 0 4 5 4 13
450-499 2 4 3 3 6 4 22
400-449 1 1 4 11 13 3 33
350-399 1 4 0 4 11 3 23
300-349 0 1 0 1 6 0 8
250-299 0 0 0 0 4 0 4
200-249 0 0 0 0 0 0 0
Total 4 11 7 25 49 18 114

------------------------------Percent------------------------------
700-749 0 0 0 0 2 6 2
650-699 0 0 0 0 2 0 1
600-649 0 9 0 0 2 6 3
550-599 0 0 0 8 2 10 4
500-549 0 0 0 16 10 22 11
450-499 50 36 43 12 12 22 19
400-449 25 9 57 44 27 17 29
350-399 25 36 0 16 22 17 20
300-349 0 9 0 4 12 0 7
250-299 0 0 0 0 9 0 4
200-249 0 0 0 0 0 0 0
Total 100 100 100 100 100 100 100


This publication was produced at a cost of $1,218.80 or $1.22 per copy, to provide information on the
prevalence and economics of liver flukes in Florida and management practices on ranches surveyed. 06-1M-90


COOPERATIVE EXTENSION SERVICE, UNIVERSITY OF FLORIDA, INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES, John T.
Woeste, director, in cooperation with the United States Department of Agriculture, publishes this information to further the purpose of the
May 8 and June 30, 1914 Acts of Congress; and is authorized to provide research, educational information and other services only to
individuals and institutions that function without regard to race, color, sex, age, handicap or national origin. Single copies of extension
publications (excluding 4-H and youth publications) are available free to Florida residents from county extension offices. Information on bulk
rates or copies for out-of-state purchasers is available from C.M. Hinton, Publications Distribution Center, IFAS Building 664, University of ... ..
Florida, Gainesville, Florida 32611. Before publicizing this publication, editors should contact this address to determine availability.




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs