Fecal Egg Count and FAMACHA Score in
Ewes
Victoria Marincheva1,*,
Kostadin Kanchev2, and Iliyan Manev1
1Department of Anatomy, physiology and
Animal Sciences, Faculty of Veterinary medicine, University of Forestry, Sofia,
Bulgaria
2Department of Infectious pathology,
hygiene, technology and control of foods from animal origin, Faculty of
Veterinary medicine, University of Forestry, Sofia, Bulgaria
ABSTRACT
Parasitic nematodes present a major
cause of economic loss that impacts the sheep industry worldwide. The
collection of scientific data from different regions and the introduction of
reliable diagnostic methods can provide the instruments for control especially
now when the situation is complicated by increased prevalence and development
of anthelmintic resistance. This
study aims to pay attention to fecal egg count (FEC) of ewes from the Southern
part of Bulgaria and try to correlate results to FAMACHA scoring in the context
of naturally occurring mixed-type gastrointestinal nematode infection.
Keywords: Gastrointestinal nematodes, Sheep,
FEC, FAMACHA
INTRODUCTION
The sheep industry in Bulgaria
comprises predominantly small-scaled farms keeping on average less than 500 to
1000 animals that are raised under grazing conditions during most of the year.
According to data from the Ministry of agriculture, food, and forestry the
total number of sheep in 2019 was equal to 1 280 983 (Bulgarian Ministry of Agriculture, Food
and Forests, 2020). Herds
are often mixed breeds with no pedigree register. Husbandry conditions can be
described as poor to average. Deworming is usually done twice a year as a mass
event and is rarely based on parasitological examination. The climate in the
country is temperate, however, the weather in the Southern parts is mild and
warm even during the winter. There are a few scientific studies on the current
parasitological situation in Bulgaria (Radev et al., 2012; Iliev, 2019).
Parasitic diseases and
gastrointestinal nematodes in the particular present among the main causes of
production loss in sheep farming that impact negatively profitability (Roeber et al., 2013b). Consequences include a
decrease in daily milk yield (Alberti et al., 2012) and a reduction in
weight gain (Ilangopathy et al., 2019) due to
inefficient food conversion (Jas et al., 2017) as well as a fall in wool
production (Liu et al., 2003; Southcott et al., 2006).
One of the most important and widely
used traits to estimate the severity of parasite burden is the fecal egg count
(FEC). The method is inexpensive and easy to perform (Roeber
et al., 2013a), though time-consuming, especially in larger herds. It
has become the golden standard for diagnostics and follow-up and has been
recommended by the World Association for the Advancement of Veterinary
Parasitology (W.A.A.V.P.).
FEC should be checked with attention
during the period of immune relaxation around parturition known as the
periparturient rise (Gibbs, 1986; Chaney, 2012). This
period is characterized by a significant increase in the number of parasite
eggs that presents a major source of pasture contamination for naïve progeny
(Sebastiano et al., 2017). Another important factor is the reactivation
of hypobiotic larvae in spring (Abbott et al.,
2012) and high fecal egg output usually one month after introduction to pasture
(El-Ashram et al., 2017).
The need for a quick diagnostic
strategy has led to the development of the FAMACHA colour
chart- a scoring system from South Africa introduced to estimate the clinical
manifestation of hemonchosis (van Wyk
and Bath, 2002). It is based on anemia level and its
relation to hematocrit results; the scoring is done against a standardized set
of five colours ranging from red-pink (normal) to
white (terminal anemia) (Malan et al., 2001).
This study aims to analyze FEC of
ewes from a typical farming system in Southern Bulgaria and attempt to
correlate results to FAMACHA scoring as well as identify the genus and species
prevalence.
MATERIALS
AND METHODS
1)
Experimental
Animals
The study was conducted from February
to May 2021 in a flock of 800 sheep from dairy breeds, predominantly 4th to 5th
generation Assaf crosses with local breeds. The experimental animals included
25 ewes during the lactation period. All were examined and found to be
clinically healthy before the initiation of the test period.
2)
Test
Procedure
Biological materials were obtained
and data were recorded in individual protocols. Blood for hematology was taken
by jugular puncture in pre-labeled tubes. Feces were collected rectally and
examined within 24 hours.
The study can be divided into three
parts. It started end of February 2021 when ewes had given birth and were in
the 6-8th week postpartum. The timing was chosen so it can coincide with the
expected rise in FEC during the periparturient period. The follow-up was
carried out at the beginning of April and then at the beginning of May when
animals were already actively grazing.
Deworming was performed in August
2020 with levamisole/oxiclosanide oral suspension and
later in December 2020 with ivermectin subcutaneously. Antihelmintics`
type and regimen were chosen by the farmer as the herd is privately owned. No
treatment was performed during the test period.
Due to the warm weather, the pasture
season began early in March.
3)
Parasitological
Methods
Parasitology was carried out
according to the modified McMaster technique using original McMaster slides
(EGGZAMIN™) as described by Zajac and Conboy (2012). Fecal egg count is
expressed as the number of eggs per gram of feces. It is an important variable
in sheep for the prevention of parasite disease and the maintenance of
efficient production.
Gastrointestinal strongyle
identification on the level of genus was based on morphological data of
nematode third-stage larvae isolated by the Modified Baermann’s test from faecal culture after performing conventional larval
cultivation (Zajac and Conboy, 2012; Kanchev et al.,
2016).
4)
FAMACHA
Scoring System
FAMACHA scoring was done with the
original FAMACHA colour chart developed by Malan et
al. (2001) and introduced by van Wyk and Bath
(2002). It is based on anemia level and its relation to hematocrit results. The
color of the eye mucous membranes is matched to a chart of five categories with
each corresponding to a definite hematocrit range. The scoring is done against
a standardized set of five colours ranging from
red-pink (normal) to white (terminal anemia) (Malan et al., 2001).
5)
Hematology
The Mindray hematology analyzer
BC-2800 Vet Automatic was used.
6)
Statistical
Analysis
Statistical analysis was conducted by
Microsoft Excel 2016. Mean values and standard deviation (X±SD), correlation
coefficient by the CORREL function, and significance value (р < 0.05) are
represented in the following section.
RESULTS
1)
Parasitological
Results
FEC
of ewes during the periparturient period (February 2021) was characterized by mean values of 688 ±554.78 EPG.
From all 25 animals,
there was 1 with FEC 50 EPG (№
13); 4 with FEC 100 to 200 EPG (№ 3, 4, 12, 24), 11 with FEC
250 to 750
EPG (№ 6, 7, 8, 11, 14, 15,
18, 21, 22, 23, 25) and 9 with FEC above 750 EPG (№ 1, 2, 5, 9, 10, 16, 17, 19, 20).
Therefore,
the percentage distribution was 4% with EPG 50, 16% with EPG 100-200, 44% with EPG 250-750, and 36% with EPG above 750.
The
examination in April 2021 showed mean values of 589.58 ±677.46 EPG. The individual
distribution was 1 animal
with EPG 0 (№ 13); 2 with EPG 50 (№ 12, 18); 6 with FEC
from 100
to 200
EPG (№ 1,
2, 3, 4, 7); 11 with EPG
250-750 (№ 6,
8, 11, 14, 15, 16, 17, 21, 22, 23, 25); 5 with EPG above 750 (№ 5, 9, 10, 19, 20). Or there was
4% with EPG 0, 8% with EPG
50, 24% with EPG
100-200, 44% with EPG
250-750, and 20%
with EPG above 750.
The follow-up in May resulted in a
mean FEC of 447.92 ±628.9 EPG. There was 1 ewe
with EPG 0 (№
11); 7 with EPG
50 (№ 1, 7, 12, 13, 18, 23, 24); 5 with FEC 100-200 EPG (№ 2, 3, 4, 8, 14); 8 with EPG 250-750 (№ 5, 6, 15, 17, 19, 21, 22, 25); 3 with EPG above 750 (№ 9, 10, 20). Or there was 4% with
EPG 0, 28% with EPG 50, 20% with EPG 100-200, 32% with EPG 250-750, and 12%
with EPG above 750.
Helminthological
study revealed the infestation with two members of Trichostrongylidae family
belonging to genera Trichostrongylus
and Ostertagia
based on nematode third-stage larvae morphology. Ewes № 5, 9, 17 were also
positive for nematodirosis based on egg
identification.
P
value is calculated: p = 0.004 for February/April, p = 0.015 for April/May, and
p = 0.0005 for February/May. Results from FEC are represented in Table 1.
2)
FAMACHA
Scoring System and Hematology
FAMACHA scoring was carried out at the beginning
and end of the test period. The mean values were 3.2 ±
0.4
in February and 3.12 ±
0.32
in May 2021. Most of the animals scored 3 according to
the original colour chart. Only a few were in
category 4.
FAMACHA
scoring is represented in Table 2. Results from hematology are represented in Table 3 and 4.
Table 1: Results from FEC (EPG) in February,
April, and May 2021
|
FEC (EPG) |
February 2021 |
April 2021 |
May 2021 |
Mean individual result |
|
MEAN |
688 |
589.58 |
447.92 |
|
|
± SD |
554.78 |
677.46 |
628.9 |
|
|
MIN/MAX |
50 / 2450 |
0 / 2800 |
0 / 2350 |
|
|
1 |
900 |
100 |
50 |
350 |
|
2 |
800 |
100 |
150 |
350 |
|
3 |
150 |
200 |
200 |
183.3 |
|
|
|
|
|
|
|
4 |
100 |
200 |
150 |
150 |
|
5 |
800 |
800 |
750 |
783.3 |
|
6 |
300 |
450 |
250 |
333.3 |
|
7 |
300 |
150 |
50 |
166.7 |
|
8 |
750 |
400 |
200 |
450 |
|
9 |
2450 |
2200 |
2350 |
2333.3 |
|
10 |
1200 |
1450 |
1200 |
1283.3 |
|
11 |
450 |
350 |
0 |
266.7 |
|
12 |
200 |
50 |
50 |
100 |
|
13 |
50 |
0 |
50 |
33.3 |
|
14 |
300 |
300 |
200 |
266.7 |
|
15 |
350 |
300 |
300 |
316.6 |
|
16 |
1350 |
350 |
100 |
600 |
|
17 |
1350 |
750 |
450 |
850 |
|
18 |
350 |
50 |
50 |
150 |
|
19 |
1400 |
1300 |
750 |
1150 |
|
20 |
1200 |
2800 |
2300 |
2100 |
|
21 |
250 |
300 |
300 |
283.3 |
|
22 |
500 |
450 |
450 |
466.7 |
|
23 |
650 |
500 |
50 |
400 |
|
24 |
150 |
150 |
50 |
116.7 |
|
25 |
400 |
450 |
300 |
383.3 |
Table 2: FAMACHA score in February and
May 2021.
|
FAMACHA score |
February 2021 |
May 2021 |
|
MEAN |
3.2 |
3.12 |
|
±
SD |
0.4 |
0.32 |
|
MIN/MAX |
3
/ 4 |
3
/ 4 |
|
1 |
3 |
3 |
|
2 |
3 |
3 |
|
3 |
3 |
3 |
|
4 |
3 |
3 |
|
5 |
3 |
3 |
|
6 |
4 |
3 |
|
7 |
3 |
3 |
|
8 |
3 |
3 |
|
9 |
4 |
4 |
|
10 |
3 |
3 |
|
11 |
3 |
3 |
|
12 |
3 |
3 |
|
13 |
3 |
3 |
|
14 |
4 |
3 |
|
15 |
3 |
3 |
|
16 |
3 |
3 |
|
17 |
3 |
3 |
|
18 |
3 |
3 |
|
19 |
4 |
4 |
|
20 |
4 |
4 |
|
21 |
3 |
3 |
|
22 |
3 |
3 |
|
23 |
3 |
3 |
|
24 |
3 |
3 |
|
25 |
3 |
3 |
Table 3: Hematology results in February 2021
|
|
WBC |
RBC |
HGB |
HCT |
MCV |
MCH |
MCHC |
PLT |
|
|
109/L |
1012/L |
g/L |
% |
fL |
Pg |
g/dL |
109/L |
|
MEAN |
10.86 |
8.91 |
99.25 |
30.58 |
34.5 |
11.12 |
334.5 |
478.23 |
|
± SD |
1.63 |
0.78 |
5.7 |
2.83 |
1.92 |
0.57 |
15.28 |
121.08 |
|
1 |
11.3 |
9.74 |
107 |
33.7 |
34.6 |
L
10.9 |
317 |
526 |
|
2 |
10.5 |
8.39 |
L
89 |
28.1 |
33.6 |
10.6 |
L
316 |
677 |
|
3 |
13.3 |
8.94 |
108 |
34.3 |
H
38.4 |
12 |
L
314 |
301 |
|
4 |
12.8 |
8.23 |
92 |
28.6 |
34.8 |
11.1 |
321 |
416 |
|
5 |
10.6 |
8.04 |
93 |
28.1 |
35 |
11.5 |
330 |
594 |
|
6 |
10.8 |
9.36 |
105 |
29.7 |
32.3 |
10.9 |
345 |
631 |
|
7 |
11 |
8.5 |
101 |
31.5 |
37.1 |
11.8 |
320 |
547 |
|
8 |
12.4 |
9.21 |
106 |
33.8 |
36.7 |
11.5 |
313 |
459 |
|
9 |
12.6 |
8.33 |
92 |
26.8 |
32.2 |
11 |
343 |
484 |
|
10 |
12.7 |
10.22 |
104 |
30.8 |
30.2 |
10.1 |
337 |
L
123 |
|
11 |
12.4 |
8.05 |
L
89 |
28.5 |
35.5 |
11 |
L
312 |
H
840 |
|
12 |
H
14.9 |
8.37 |
L
87 |
27.2 |
32.6 |
10.3 |
L
319 |
L
100 |
|
13 |
8.8 |
7.81 |
96 |
30.6 |
H
39.3 |
12.2 |
L
313 |
427 |
|
14 |
10.4 |
L
7.43 |
L
88 |
26.9 |
36.3 |
11.8 |
327 |
487 |
|
15 |
8.6 |
8.19 |
97 |
31 |
37.9 |
11.8 |
L
312 |
349 |
|
16 |
7.4 |
9.02 |
95 |
29.1 |
32.3 |
10.5 |
326 |
497 |
|
17 |
10.6 |
10.12 |
93 |
35 |
32.6 |
11.2 |
347 |
473 |
|
18 |
11.4 |
9.63 |
104 |
32.7 |
34 |
10.7 |
L
318 |
360 |
|
19 |
8.9 |
8.3 |
91 |
28 |
33.8 |
10.9 |
325 |
813 |
|
20 |
8.6 |
L
7.5 |
L
89 |
L
25.1 |
33.5 |
11.8 |
354 |
540 |
|
21 |
10.9 |
10.14 |
102 |
26.5 |
36.2 |
11 |
328 |
437 |
|
22 |
10.7 |
8.28 |
97 |
29.7 |
34.7 |
10.6 |
362 |
458 |
|
23 |
12.6 |
8.47 |
96 |
35.2 |
34.1 |
10.3 |
316 |
356 |
|
24 |
8.6 |
9.32 |
108 |
33.4 |
37.3 |
11.4 |
348 |
321 |
|
25 |
12.8 |
10.35 |
98 |
34.7 |
36.1 |
10.8 |
362 |
368 |
Table 4: Hematology results in May 2021
|
|
WBC |
RBC |
HGB |
HCT |
MCV |
MCH |
MCHC |
PLT |
|
|
109/L |
1012/L |
g/L |
% |
fL |
Pg |
g/dL |
109/L |
|
MEAN |
9.58 |
8.9 |
99.25 |
30.59 |
34.5 |
11.14 |
336.65 |
463.19 |
|
± SD |
1.78 |
0.69 |
5.39 |
2.35 |
2.04 |
0.62 |
14.54 |
159.56 |
|
1 |
9.8 |
9.24 |
103 |
31.6 |
34.3 |
11.1 |
325 |
614 |
|
2 |
9.6 |
7.97 |
L 82 |
26.3 |
33 |
10.2 |
L 311 |
389 |
|
3 |
H 16.2 |
7.93 |
92 |
29.1 |
36.8 |
11.6 |
L 316 |
210 |
|
4 |
8.3 |
9.44 |
106 |
32.5 |
34.5 |
11.2 |
326 |
328 |
|
5 |
8.8 |
10.79 |
109 |
31.8 |
29.5 |
10.1 |
342 |
515 |
|
6 |
8.9 |
8.23 |
98 |
30 |
36.5 |
11.9 |
326 |
H 728 |
|
7 |
12.4 |
8.65 |
104 |
32 |
36.4 |
11.6 |
361 |
620 |
|
8 |
12.6 |
9.23 |
106 |
32.9 |
35.7 |
11.4 |
322 |
422 |
|
9 |
9.2 |
8.49 |
105 |
33 |
36.8 |
11.8 |
337 |
547 |
|
10 |
8.5 |
9.44 |
93 |
36 |
34.7 |
11.6 |
328 |
275 |
|
11 |
8.9 |
8.3 |
91 |
29.2 |
35.2 |
10.9 |
L 311 |
558 |
|
12 |
H 17.1 |
8.84 |
92 |
28.1 |
31.9 |
10.4 |
327 |
L 132 |
|
13 |
H 14.3 |
L 7.46 |
L 88 |
28.2 |
37.9 |
11.7 |
L 312 |
245 |
|
14 |
9.3 |
9.4 |
L 89 |
34 |
35.6 |
11.9 |
371 |
614 |
|
15 |
9.6 |
8.34 |
98 |
31 |
37.2 |
11.7 |
L 316 |
180 |
|
16 |
9.5 |
9.3 |
97 |
29.7 |
32 |
10.4 |
326 |
645 |
|
17 |
10.6 |
8.64 |
99 |
30.3 |
35.1 |
11.4 |
326 |
603 |
|
18 |
H 14.5 |
9.81 |
104 |
32 |
32.7 |
10.6 |
325 |
L 105 |
|
19 |
6 |
L 7.34 |
L 80 |
L 25.4 |
34.7 |
10.8 |
L 314 |
651 |
|
20 |
13.6 |
7.91 |
91 |
L 25.9 |
32.8 |
11.5 |
351 |
291 |
|
21 |
H 14.1 |
8.2 |
100 |
29.4 |
35.9 |
12.1 |
340 |
L 135 |
|
22 |
11.1 |
8.59 |
L 87 |
26.3 |
30.7 |
10.1 |
330 |
292 |
|
23 |
6.8 |
9.2 |
96 |
28.3 |
34.9 |
10.3 |
354 |
641 |
|
24 |
8.3 |
9.46 |
101 |
29.6 |
33.8 |
10.8 |
358 |
573 |
|
25 |
9.7 |
9.23 |
100 |
32.3 |
34.1 |
11.4 |
327 |
514 |
Ewes that fall in category 3 are assumed to
be normal as they also show hematological results within the reference range.
Individuals that scored 4 or had pale/anemic mucus membranes included № 6, 9,
14, 19, 20 in February and № 9, 19, 20 in May. It is observed that № 9, 19, and 20 repeats, while the score of № 6 and 14
has become 3.
As long as the FAMACHA system was developed
for visual estimation of anemia, results should be compared with data from
hematology. Ewes № 6 and 9 show no changes in CBC. Ewe № 14 is characterized by
a decrease in RBC, hemoglobin, PCV in February, but
only hemoglobin remains insignificantly low in May.
Changes in RBC, hemoglobin, PCV, MCHC are seen in ewe № 19 in May. Ewe № 20
shows low RBC, hemoglobin, PCV in February, and hemoglobin in May.
The correlation coefficient between FEC and
FAMACHA equals 0.416 in February and 0.813 in May.
DISCUSSION
The analysis of results shows that the
percentage of animals with medium to high FEC (EPG 250-750) was 44% in February
and April but decreased to 32% at the end of the study. Individuals with high
FEC (EPG above 750) account for 36% during the periparturient period and
decrease to 20% in April and 12% in May. The percentage of animals with low FEC
(EPG 50) is characterized by increasing values: from 4% in February to 8% in
April and 28% in May; from April on there are 4% with EPG 0.
The difference between test results is
statistically relevant as manifested by the calculated p-value. This is better
pronounced between February/April (p = 0.004) and February/May (p = 0.0005).
The value is less significant when comparing April/May (p = 0.015), as test
results become more evenly distributed after the end of the critical
periparturient period.
Changes in mean values are also relevant. Mean
FEC decreased from 688 ± 554.78 EPG in February to 589.58 ± 677.46 EPG in April
and 447.92 ± 628.9 EPG in May though it could be expected that FEC should rise
with the beginning of the pasture season and the spring warming. It should be
noted again that the number of animals with high FEC decreased, while those
with low FEC increased. This can be explained by the recovery of the immune
response after the end of the critical periparturient period (Abbott, 2018). It
is speculated that the rise in FEC can be due to low levels of antibodies in
the gastrointestinal tract which allows the attachment of larvae and/or the
activation of parasites from the state of hypobiosis
(Jeffcoate et al., 1992). After hypobiosis adult worms are capable of producing a large number
of eggs (Gibbs, 1986), which can be the reason for the high percentage of ewes
with FEC equal to or above 750 EPG.
The ability of an individual to limit or
reduce the parasite load represents its natural resistance. This concept is
widely discussed as a part of the sustainable parasite control approach (Hoste and Torres-Acosta, 2011). Therefore, it is worth
dividing animals from this experiment into several groups.
The first group includes animals that show
constantly low FEC (below 250 EPG). These are ewes № 3, 4, 12, 13, 24. This
category can include ewes that are characterized by low FEC after the initial
increase during the periparturient rise like ewe № 7.
Ewes with high FEC (above 750 EPG) include №
5, 9, 10, 19, 20. It is important to note that ewes № 5, 9, and 17 were also
positive for nematodirosis.
The other animals can be categorized as
having medium FEC (250-750 EPG). However, certain animals cannot be classified
so straightforwardly. For example, ewes № 1, 2, and 16 with high FEC during the
periparturient rise but significantly low in April and May (50-150 EPG). Ewe №
17 may also be included though the decrease in FEC is not as prominent.
The parasite invasion is controlled by
mechanisms that suppress the growth, establishment, and survival of nematodes; however,
the immune response to species that are localized in the abomasum is slower
(McRae et al., 2015). The competence of the immune reactivity ensures
the expulsion of adult worms and reduced fecundity of females (Kemper et al.,
2010; Hendawy, 2018). An interesting phenomenon is
the so-called “self-cure effect” when larvae and adult parasites are removed
from the organism without the intake of anthelmintics (Garza, 2014). The
expulsion relies on mucin hypersecretion (Benavides et al., 2016), high
levels of histamine and leucotrienes as well as
increased peristalsis (Alba-Hurtado and Muñoz-Guzmán, 2012).
It can be speculated that animals from the
last group developed a “self-cure” reaction which resulted in the decrease in
FEC. As it was mentioned ewes were regularly dewormed, but not during the
experimental period. Nevertheless, results from FEC were predominantly medium
to high in the February testing probably due to the consequences of the
periparturient rise. However, many animals were able to withstand or overcome
the infection which is demonstrated by the overall decrease in EPG.
The division into groups of low/medium/high
FEC is useful to direct treatment decisions on the individual and herd levels.
This method can also be applied as a selection tool to estimate the level of
resistance/tolerance of sheep to gastrointestinal nematodes (Gauly and Erhardt, 2001; Vanimisetti
et al., 2004; Bishop, 2009; Greeff et al., 2009; Bishop, 2012; Valilou et al., 2015). FEC is an important variable
with known intermediate inheritance (Smith et al., 1999) that can
influence the distribution of parasites within the population. It can be
measured regularly to estimate the adverse effects of parasitism. Set as a selective trait in reproductive animals or as an indicator of
infection severity, it can be used for decision-making about the selective
treatment of the herd or the individual animal. The application of deworming to
the whole population once or twice a year is no more recommended due to the
possibility of parasite resistance and the wider concept of the benefits of
refugia (van Wyk, 2001; van Wyk
et al., 2006).
The finding of Trichostrongylus
and Ostertagia nematodes indicate the possible wide
spread of trichostrongylides among the population of
sheep on pasture housing technology in Bulgaria which has been discussed in
other regional studies as well (Radev et al.,
2012; Iliev, 2019).
According to many authors FAMACHA score can
be well correlated to a decrease in PCV in gastrointestinal nematode infections
(Kaplan et al., 2004; Burke et al., 2007; Assefa, 2015). However,
results from the current experiment showed that the method is not reliable
enough to predict the presence of anemia. It should be mentioned that the
system is specifically directed to the clinical consequences of hemonchosis. The infection in the Bulgarian context is
expected to be mixed and there can be other blood-sucking species present (Di
Loria et al., 2008; Radev et al., 2012;
Iliev, 2019). The manifestations can also be
influenced by the ratio between different parasites (Douch et al.,
1996). Therefore, FAMACHA should not be used independently but can supplement
the clinical examination. Information about the application of the colour chart in Europe is still insufficient but the
conclusions published by Di Loria et al. (2008) are in accordance.
The correlation between FEC and FAMACHA is
also widely discussed. Studies suggest that a higher FAMACHA score corresponds
to a higher FEC (Notter et al., 2017; Galyon et al., 2020). However, the increase in FEC
is variable (Cintra et al., 2018). In the case of this experiment, ewes
№ 9, 19, 20 are scored FAMACHA 4 and have high FEC; ewes № 5,10 are
characterized by high FEC, but the FAMACHA score is 3; ewes № 6, 14 belong to
the group with medium FEC and their FAMACHA score is changed from 4 in February
to 3 in May. Again, the sensitivity of FAMACHA scoring is not reliable enough
to predict the rise in FEC.
The correlation coefficient between FEC and
FAMACHA was calculated and interestingly it was high enough: 0.416 in February
and 0.813 in May. Therefore, statistically the two variables are positively
correlated and should be considered together.
Estimating the effects of gastrointestinal
parasitism based on reliable parameters such as FEC, FAMACHA scoring and
hematology represents a promising approach to the prophylaxis of these
economically relevant diseases. Decisions that help to lower the costs and
reduce the losses in animals or production should be investigated and then
incorporated into practice.
CONCLUSION
Results from the current study were able to
identify the periparturient rise in ewes and perform a follow-up examination at
the beginning of the grazing season based on the standard FEC technique. The
introduction of the FAMACHA scoring system was aimed at as an additional tool
in diagnostics. It can be recommended that these variables are estimated
together with hematology to aid treatment decisions. Furthermore, routine
testing can be utilized in the effort to select sheep that are possibly
resistant or tolerant to gastrointestinal nematodes as a part of the
sustainable parasite control approach.
CONFLICT OF INTERESTS
The authors declare no
potential conflict of interest is reported regarding the subject matter of this
manuscript either for financial, commercial, or intellectual purposes
FUNDING
The authors received no financial support for the research,
authorship, and/or publication of this article.
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