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Efficacy of blood plasma IGF I as a marker and implications of fermented yeast culture in
improvement of growth performance of low body weight Murrah buffalo calves
Anand Laxmi*1, Gorakh Nath*2 and Shiv Prasad.**3
1&3 Principal Scientist, 2 MVSc. scholar,* DCP division, ** LRC I/c
National Dairy Research Institute, Karnal, Haryana 132 001 India
Contact author’s1 Phone no. 091-01842259075 Email id alnand44@gmail.com
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ABSTRACT: To find relationship between plasma IGF I and Haptoglobin and body weight in
low body weight male and female Murrah calves and to increase the body weight by
supplementation of fermented yeast culture and study its effect on blood plasma parameters.
According to the technical program low body weight (BW) Murrah calves (male and female) of
100±10kg BW at ten months of age were selected from the animal herd. The experiment was
carried out between November 2012 and March 2013. They were divided into control and
experimental groups respectively. In the experimental group supplementation of fermented yeast
culture Saccharomyces cerevisiae (SC), was done by mixing it along with concentrate
(300g/quintal). In each group for both male and female calves, there were six numbers of
animals. To the control group, SC was not offered with diet. In blood plasma IGF I and
Haptoglobin were estimated. It was observed that in both male and female supplemented groups,
the body weight, concentration of plasma IGF I, Haptoglobin, average daily gain increased
significantly. It can be concluded that the results obtained with concentration of plasma IGF I,
and body weight of male or female calves inferred that animals with less body weight exhibited
less concentration of the plasma hormone and increased with the supplementation. A positive
relationship was observed between plasma IGF I and body weight gain. This may be due to
increase in feed conversion efficiency and digestibility of certain nutrients , due to
supplementation of fermented yeast culture, which is
an economic and non invasive
biotechnological tool resulting in increase in growth performance of low body weight male and
female Murrah buffalo calves. This is an important step suggesting for advancement of puberty
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at later stages. IGF I in Murrah calves can act as a physiological indicator for growth
performance.
Key words: Murrah calves, Body weight, Plasma IGF I, Fermented yeast culture
INTRODUCTION
Management practices as well as environmental and pathological stresses have an impact on
growth performances and health status of calves. Plasma Insulin like growth factor I (IGF I) has
been implicated in post natal growth, reproduction and immune function. Haptoglobin is a
sensitive marker for determining health status of cow. Plasma IGF I can be used to identify
animals differing in their growth rate and productive ability. The somatomedins, IGF I, have
been implicated as being involved in many biological processes which includes pre and postnatal
growth, lactation, reproduction, and immune function. The growth of the organism is dependent
on many endocrine factors and plasma IGF I is one endocrine factor (Ong et al., 2007). It plays a
significant role in the control of growth in cattle (Lucy, 2008; Ortega et al., 2008; Lancaster et
al., 2008). Elevation of serum Haptoglobin (HP) level is generally non specific with regard to the
nature of the inciting agent and therefore can be used to gauge the extent and activity of many
different pathological processes (Horadagoda et al., 1999). One of the best feed additives not
only for sheep ration but also for all ruminant rations is the fermented yeast cultures or Direct
Fed Microbial (DFM), which are viable microbial cultures and enzyme preparations that
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beneficially affect the animal by improving its intestinal microbial balance. Supplementation of
SC to low body weight calves also, increased the body weight gain in cross bred HF calves
(Anand Laxmi et al., 2012). Similar reports are available in other species (Haddad and Goussous,
2005; Kim et al., 2010). Feeding 50g/day of yeast culture to water buffalo calves did not
improve weight gain (Ramirez et al., 2007). The hypothesis is that instead of discarding the low
body weight calves, some simple tool can be applied which can increase the body weight of
calves, which in turn may be useful for augmenting puberty also.
MATERIALS AND METHODS
All animal-related procedures used in these studies were approved by the Institutional Animal
Ethics Committee (IAEC). Blood samples were collected at weekly intervals from twenty four
number of Murrah buffalo calves when they were ten months old and continued till they attained
fourteen months of age for studies on growth performance. Body weight of the calves was
recorded at monthly intervals. The Mean ± SE values for each parameter was computed for 30 d.
The body weight (BW) of calves was low. Average body weight was 110±10 Kg. Blood samples
were collected daily before 8.00 am and feed offered at 8.30 am in the morning daily. The
samples were centrifuged at 3000 rpm for 20 minutes; plasma was separated and stored at -200
C, till further assay of the hormones. The diets were formulated based on recommendations of
the NRC (NRC, 2001). Wheat straw and concentrate were offered in the ratio 1:1 @ 3 kg/100 kg
BW. Greens were offered @ 2.5 kg/calf/day till fourteen months of age. The weight of the
residue feed was also recorded. The selected LBW calves were divided into two groups
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consisting of six number of Murrah calves in each group. One group served as control, which
was not supplemented fermented yeast culture and experimental groups for both male and female
buffaloes (6 nos. each) was supplemented with fermented yeast culture (FYC) @
12g/animal/day. The bovine IGF I assay kit was purchased from CUSA BIOTECH Co. LTD.,
(USA), Haptoglobin assay kit was purchased from Immunology Consultants laboratory Inc.
(USA). The assay was performed according to the protocol given along with the kit. The intra
and inter assay coefficient of variation was less than 5%. The feed conversion ratio (FCR) and
feed conversion efficiency (FCE) was calculated with respect to dry matter intake (DMI), feed
residue, and BW parameters. A digestibility trial of seven days collection period was conducted
after 60 d of experimental feeding to determine digestibility of dry matter and nutrients. The
sample of feeds, faeces and refusals were analyzed for proximate constituents (AOAC, 1995).
The Kjeldahl method for nitrogen analysis was used for crude protein determination, using a
1031 Kjaltec analyser (Tecator, Sweden) and multiplying the result by 6.25.
Statistical analyses: Statistical analysis was carried out using Microsoft office excel 2007. For
body weight and plasma parameters data was statistically analyzed by SAS software, version
(9.1) of the SAS system for window copy right 2011, SAS Institute Inc., Cary, NC, USA. Data is
expressed as Mean ± SE and analyzed by ANOVA, Results exhibiting significant effect were
compared by the least significant difference pair wise multiple comparison test. Difference was
considered statistically significant at P<0.05 .The data is presented as Mean±SE. Differences
between groups for digestibility coefficient were evaluated by independent t test. Level of
significance was set at P<0.05.
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RESULTS AND DISCUSSION
The effect of supplementation of fermented yeast culture on Means (±SE) of BW (kg) of the
experimental and control groups at 30-days interval is presented graphically in Fig. 1. At the
beginning of supplementation of fermented yeast culture, the body weights of experimental and
control group of animals did not differ significantly (P > 0.10; Fig. 1), and it was low. The range
of ADG for control group was 0.43-0.70kg/d, and for experimental group was 0.53-1.0 kg/d
during 150 d of study tenure. In the females the range for ADG for control group was 0.530.77kg/d and for experimental group was 0.50-1.07kg/d. There was significant increase (P <
0.05) in least square mean (LSM) of the BW and ADG of fermented yeast culture supplemented
group when compared with control group during the treatment period in both male and female
calves (Table-2). Supplementation of Saccharomyces cerevisiae to calves improved feed
intake/live weight gain and decreased effect of transport stress (Fallon and Harte, 1987; Anand
Laxmi et al., 2012).
After sixty days of supplementation of fermented yeast culture to low body weight (LBW)
Murrah buffalo calves, an increase in Mean±SE of plasma IGF-I concentration (42.66 ± 0.84 vs.
55.75±0.45; 42.63±0.48vs.58.32±0.38 ng/ml) was observed in both male and female calves.
Supplementation for further sixty days, the concentration of plasma IGF I increased significantly
(P<0.05) in both male and female calves from the concentration recorded at thirty days of
supplementation (42.66 ± 0.84 Vs 67.23± 0.36; 42.63±0.48vs.70.23±0.41 ng/ml). In the control
group (males) the plasma IGF-I increased only at 120 days with no further significant increase
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till 150 d of experiment, whereas in females it increased at 90d with no further significant
increase in the plasma concentration of the hormone (Table 1). A significant difference (P<0.05)
in (LSM) value was observed between groups (Table 2). The concentration of plasma Hp was
not significantly different between the two groups throughout the course of the study and was
within physiological range <500ng/ml (Table 2) in both male and female calves. The present
study is an attempt to establish the circulatory plasma IGF-I and Haptoglobin in low body weight
Murrah buffalo calves. It was also to assess, if supplementation of commercially available
fermented yeast culture, along with diet could improve the circulatory plasma IGF-I
concentration with an increase in the body weight gain and the possibility of using IGF-I as a
marker for growth performance under tropical conditions. LSM value for the monthly body
weight gain (BWG) resulted in significant increase (P<0.05) in body weight gain of 17.21 ±
1.24 Kg in control group and 26.22 ± 1.24 Kg in the supplemented group of male Murrah calves
where as in females also similar body weight gain was observed (Table 2). In control group
LSM value for ADG of 567 g/male animal was achieved where as in females it was 633g could
be easily achieved under proper care of individual calves, but supplementation of fermented
yeast culture @12g/animal/d could further increase the potential of ADG to 867 and 887
g/animal in males and females respectively, which strongly paralleled with the increase in
plasma IGF-I in the experimental group (Table 2). A strong positive correlation has been
reported between ADG, age and plasma IGF- I (Torrentera et al., 2009). With increase in age
and body weight of pigs, increase in plasma level of IGF-I has also been reported (Cameron et
al., 2003). It is known that plasma IGF-I level is a potential physiological indicator, since it is
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Table 1. Mean±SE of different parameters in male and female Murrah calves
Days
30
60
90
120
150
Male
IGF I
Control
42.89 ± 0.58
48.45± 0.34
48.65± 0.32
52.23a± 0.51
54.23± 0.32
Experimental.
42.66 ± 0.84
53.93± 0.45
55.75*± 0.45
59.82*± 0.41
67.23*± 0.36
14.5±0.92
20.2±1.2
17.2±0.82
21.4±1.24
16.4±0.99
26.3*±0.54
29.3*±0.98
25.4*±1.02
30.01*±1.23
Control
43.52± 0.52
48.23± 0.49
52.96± 0.23
52.36± 0.36
53.98± 0.45
Experimental
43.63± 0.48
48.78± 0.45
58.32*± 0.38
64.52*± 0.43
70.23*± 0.41
Control
16.2±0.98
19.12±1.02
15.42±1.13
22.21±1.02
23.30±0.96
Experimental
15.3±0.88
26.22±1.23
29.32*±1.22
31.25*±1.14
32.15*±1.01
BWG
Control
Experimental
13.2±0.85
Female
IGF I
BWG
IGF I = Insulin like growth factor I (ng/ml), SE = Standard error, BWG-body weight gain
(kg/30d). Each group contained six numbers of calves. Control- Group without supplementation
of FYC, Experimental- Group supplemented with FYC,*P<0.05(between groups)
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Table 2.
Least square mean (LSM) of different body weight parameters and plasma parameters
for 150d of experimental period
Male
Female
Parameters
Control
Experimental
SE
Control
Experimental
SE
BW(kg)
157.20
182.6*
5.27
168
187*
5.05
ADG ( g/d)
567
867*
41.5
633
887*
57.50
BWG (Kg)
17.21
26.22*
1.24
19.40
26.6*
1.45
51.23
59.17*
1.91
50.94
59.69*
2.08
345.53
352.70
8.95
412.64
350.46
12.23
IGF I (ng/ml)
Hp(ng/ml)
Body Weight (BW) , Av. Daily Gain (ADG) , Body Weight Gain (BWG) , Insulin Like Growth
Factor-I (IGF I), Haptoglobin (Hp) Av. =Average, SE = Standard Error of LSM
Control- Group without supplementation of FYC, Experimental- Group supplemented with FYC
Each group contained six numbers of calves. .*P<0.05(between groups)
not secreted in a pulsatile manner and associated with gain in body weight and growth rate
(Davis et al., 1995). Plasma IGF-I has been implicated in pre- and postnatal growth, lactation,
reproduction and immune function, and is produced primarily in the liver, although many other
tissues also produce smaller quantities of it. Davis and Simmen (2010), reported that reductions
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in serum IGF-I concentration due to inbreeding may contribute to the decline in BW and BW
gains.DMI was not significantly different between control and experimental groups in both
males and females throughout the course of the study. The daily dry matter intake (DMI)
calculated in terms of kg/100 kg BW was also not significant. This is in agreement with Kumar
and Ramana (2008) and Kumar et al., (2011) who reported non-significant decrease (P>0.05) in
DMI (kg / 100 kg BW). It has similarly been reported by Vyas et al., (2014). However,
contradictory observations with respect to DMI (Putnam et al., 1997) upon yeast
supplementation have also been reported. In the supplemented group in both male and females,
the digestibility co-efficients of dry matter (DM), organic matter (OM), ether extract (EE) and
crude fiber (CF) was observed to be significantly more (P<0.05) when compared with control,
while the increase in crude protein digestibility (CPD) in the experimental group, was not
significantly different (Table 3). The improvement in digestibility could be due to increased rate
of fiber breakdown (Haddad and Goussous, 2005). Improvement in digestibility of nutrients in
ruminants on feeding Saccharomyces cerevisiae has been reported by Mahender et al., (2006),
and Kumar and Ramana (2008). The fermented yeast culture provides soluble growth factors
(i.e., organic acids, B vitamins, and amino acids) that stimulate growth of ruminal bacteria that
utilize lactate and digest cellulose (Callaway and Martin, 1997). These growth factors may
stimulate synthesis and secretion of IGF I from liver on absorption from gastrointestinal tract.
The increased digestibility of nutrient may be due to improvement of microbial activities
(Tricarico et al., 2006; Chevaux and Fabre, 2007); increased ruminal anaerobes and cellulolytic
bacteria (Jouany, 2001) .
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Table 3 Mean±SEM of different feed parameters in Murrah buffalo calves subjected to
digestibility trial.
Male
Parameters
Control
Female
Experimental
Control
Experimental
DMI
( Kg/d)
5.48± 0.75
5.27±0.41
6.50±0.21
6.03±0.41
(Kg/100Kg BW)
2.83±0.07
2.72±0.04
2.85±0.03
2.76±0.05
Dry matter
54.70±0.85
60.85*±1.56
60.14±0.71
63.76*±0.52
Organic matter
60.36±0.67
63.99*±1.42
61.34±0.39
65.26*±0.39
Crude protein
58.74±0.98
61.75±0.77
60.59±0.58
63.69±0.82
Crude fiber
53.30±0.67
56.32*±0.62
54.43±0.26
57.71*±0.56
Ether extract
68.32±0.52
70.69*±0.41
68.11±0.79
71.62*±0.41
Feed conversion
ratio
Feed conversion
efficiency (%)
12.78*±0.84
8.89±0.81
11.54*±0.73
8.52±0.34
7.92±0.52
11.55*±1.21
8.77±0.57
12.02*±0.61
Digestibility (%)
DMI = Dry matter intake, SEM = Standard error of means, % = percentage
Control- Group without supplementation of FYC, Experimental- Group supplemented with FYC
Each group contained six number of calves.*P<0.05 (between groups)
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Figure 1.
Body weight of male and female Murrah buffalo calves during pre and post
supplementation period
Control- Group without supplementation of FYC, Experimental- Group supplemented with FYC
Each group contained six numbers of calves.
Initiation of supplementation of FYC.
*P<0.05 (between groups)
and utilization of residual oxygen to maintain anaerobic environment of rumen (Calsamiglia et
al., 2006). The supplementation of Saccharomyces cerevisiae culture at recommended doses
improves fiber digestion and reduces lactate accumulation in the rumen. Growth of yeast in the
rumen utilizes the trace amounts of dissolved oxygen and thereby stimulates growth of rumen
bacteria, which may be beneficial for fiber break down. It is also known that they utilize end
products of fiber fermentation to prevent their accumulation, which may alter pH of the rumen
and hence maintains congenial atmosphere in the rumen. Dietary supplementation of yeast
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cultures (YC) have been reported to increase bodyweight (BW) gain and feed conversion
efficiency of bulls (Mutsvangwa et al., 1992). Inclusion of YC from Saccharomyces cerevisiae
strains in rations of ruminants has been shown to alter molar proportions of ruminal volatile fatty
acids (Beharka et al., 1991).Contradictory reports are available, as no effect of YC
supplementation was observed on nutrient digestion in sheep (Garcia et al., 2000) or ruminal
fermentation (Arcos-Garcia et al., 2000). The increase in nutrient digestibility observed in the
present study agrees with Wiedmeier et al. (1987), Haddad and Goussous (2005), who observed
an increase in digestibility of CP and hemicelluloses of diet fed to lactating cows, suggesting that
adding YC could have stimulated rumen fermentation. Panda et al., (1995) reported beneficial
effect of supplementation of yeast culture in preruminant calves, on feed conversion efficiency
and digestibility of nutrients. The Mean±SEM of FCR was significantly less (P<0.05) for the
experimental group when compared with control group (8.89±0.81 vs. 12.78±0.83) (Table 3),
whereas the Mean±SEM of FCE was significantly more (P<0.05) for the experimental group
(11.55±1.21 vs.7.92±0.51) in male calves. Similar results were obtained with female
experimental group of calves (Table 3). Feed efficiency is an important parameter to identify
cattle that are more economic to produce (Lancaster et al., 2008) and IGF I has been attributed
an important role in nutrient utilization (Moore et al., 2005). The significant increase in the body
weight of calves during growth phase may be due to increase in plasma IGF I level. It may also
advance the age of puberty in these buffaloes, which, usually attains late sexual maturity. It was
suggested by Bhatti et al., (2007) that under tropical conditions forage along with concentrates
and other performance modifiers should be supplemented to gain a faster growth rate to attain
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early puberty. Supplementation of fermented yeast culture which is an economic non invasive
biotechnological tool to growing low body weight Murrah calves enhanced some of the
parameters. IGF I can act as a marker for growth in Murrah buffalo calves. Plasma IGF I can act
as a marker for screening Murrah calves based on body weight, and BW of low body weight
calves can be increased on supplementing feed additive like fermented yeast culture.
ACKNOWLEDGEMENTS
Acknowledgements are due to Indian Council of Agricultural Research, New Delhi, INDIA, for
providing financial assistance to carry out the research work.
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