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Research Article
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Effect of Green Forage Type on Productive Performance and Milk
Composition of Lactating Egyptian Buffalo
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A.E.M. Mahmoud
and
H.M. Ebeid
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ABSTRACT
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The objective of the present study was to investigate the effect of inclusion
different types of forage in dairy buffaloes rations on the performance of milk
production. Twelve multi parous Egyptian buffaloes, after 8 weeks of calving
(averaged 550 kg live body weight) were assigned into three groups of 4 buffaloes
in 3x3 Latin square design. Each group fed one of the three rations with different
kind forage either berseem (R1), berseem plus corn silage (R2) or corn silage
(R3). All groups were fed forage plus Concentrate Feed Mixture (CFM) by 50%
concentrate: 50% roughage. The digestibility coefficients of DM, CP, CF and
cellulose were significantly higher for R1 compare to other tested rations.
However, no significant differences noticed among tested rations for OM, EE,
NFE, NDF, ADF and hemicelluloses. All tested rations, had nearly similar values
of TDN and DE. R1 contained (B) had the highest DCP value (11.81%) followed
by R2 (10.25%) contained (B+CS) while R3 contained (CS) had the lowest value
(8.63%). No significant differences among the tested groups in both actual and
7% FCM yields. In addition, there were insignificant differences between animals
fed all tested rations in lactose, ash and SNF of milk produced. While feeding
both kinds of forages (B+CS) and CFM (R2) were significantly increased fat,
protein and TS contents compared with feeding R1 and R3. No significant differences
were observed among tested groups for feed efficiency as the amount of DM required
to produce one kg 7% FCM. While highly significant differences among treatments
were detected concerning DCP efficiency. Normal ranges for the blood parameters
were observed with no significant differences as the result of feeding all tested
rations. Short chain fatty acids were significantly higher with ration contained
berseem compared to with rations contained corn silage which had higher values
in long chain fatty acids.
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Received: September 28, 2013;
Accepted: November 11, 2013;
Published: March 11, 2014
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INTRODUCTION
Major components of raw milk include the water carrier, fat protein, lactose
and minerals. Variations in the content or composition of these milk components
are the results of genetic selections and dietary managements. Genetics determines
the relative ability of mammary cells to synthesize and secrete components of
milk, where dietary management influence availability and composition of the
nutrients used for milk component synthesis. However, concentration and thus
yield of milk fat and a much lesser extent of milk protein can be manipulated
through diet management (Bachman, 1992).
Feeding management practices of the dairy farm can have a major impact on the
levels of milk fat and protein concentration in milk. Nutritional strategies
that optimize rumen function also maximize milk production and milk components.
However, there are several strategies that producers can use to enhance rumen
function and the resulting milk components. However, nutritional strategies
that impact milk components include adequate rumen degradable protein and adequate
pounds of forage NDF in the diet especially for early lactation cows (Varga
and Ishler, 2007).
Concentration of fat in milk can vary over a range of about 3 percentage units
through diet manipulation. In contrast, lactose and minerals and the other solids
contents of milk is not responsive whereas the protein percentage can be varied
0.6 units (Bachman, 1992; Varga and
Ishler, 2007).
The kind and type of forage fed to dairy cows influences greatly milk production
and farm profitability. Species differ widely in chemical composition, nutrient
digestibility and of digestion (Bachman, 1992). Chemical
composition of grass and legume are distinctively different CP content is generally
lower for grass than legumes; however the composition of the crude protein differs.
Grass contains more non-protein nitrogen in soluble protein and legumes contain
more amino acids or peptides in soluble crude protein (Varga
and Ishler, 2007).
The FA profile of milk fat can be modified by feeding strategies and there
may be longer-term options by animal breeding. There are possibilities for a
chain-approach from farm to processor to consumer, some examples were presented
and such an integrated approach is essential if scientific findings are to be
put into practice. However, there remain questions about human health claims
of various milk FAs. Research
and standard protocols, for sampling, storage and FA analysis in forages are
needed and there is current research underway in this area in many parts of
the world.
This study was carried out to investigate the effect of inclusion different
type of forage (Berseem or corn silage) in dairy buffaloes rations on the performance
of milk production.
MATERIALS AND METHODS
This study carried out at the Experimental Station of Animal Production Department,
Faculty of Agriculture, Cairo University, Giza, Egypt. The experiment lasted
for 90 days Latin square design.
Ensiling procedures: Whole corn plants were chopped to make corn silage.
Silage was kept underground inside the silo with dimensions of (4x3x1.5 m length,
width and height). The walls of the silo were covered with polyethylene sheet
and the top of the silo was covered by a thin layer of polyethylene sheet (1.0
mm), then a clay layer of approximately 20 cm thickness was spread over the
polyethylene sheet for 10 weeks.
Experimental animals and rations: Twelve lactating multiparous Egyptian
buffaloes (in 3rd and 5th lactation seasons) weighed 550
kg on average were used after 8 weeks of calving, they were assigned into three
groups of 4 buffaloes. Each group of buffaloes feed one of the three rations
with different content of forage either Berseem (B), Berseem plus Corn Silage
(BCS) or Corn Silage (CS) in 3x3 Latin square design. Animals in the experimental
groups were fed forage plus concentrate feed mixture in mash form (CFM) by 50%
concentrate: 50% roughage.
Feeding procedures: Animals were individually fed on the experimental
rations to cover energy and protein requirements according to Ghoneim
(1964). The CFM was offered to all animals at milking time (7.0 am and 7.0
pm). Green forages were offered twice daily (9.0 am and at 3.0 pm). The animals
received sodium bicarbonate (as a buffer) at 1% of total dry matter intake when
fed corn silage. Water was available at all times. The daily offered and orts
were individually recorded for each animal.
Milk yield and composition: Buffaloes milk was obtained by hand milking
twice daily (7.0 am and 7.0 pm) and the daily milk yield was individually recorded
and was corrected to 7% FCM by the following equation according to Raafat
and Saleh (1962):
7% FCM = 0.265*milk yield+0.5*fat yield
Milk sampling and analysis: During the 7 days collection period two
milk samples were individually collected from each buffaloes at 7.0 am and 7.0
pm and were composite. Chemical analysis of milk fat, protein, solids not fat,
total solids and ash were determined according to Ling (1963).
Lactose was calculated by difference. Saturated, unsaturated and total fatty
acids were determinate in the fat of the milk after extraction by using methyl
ester boron trifluoride method (AOAC, 2000). The fat is
saponified with sodium hydroxide in methanol. The fatty acids are methylised
with boron trifluoride in methanol, extracted with heptane and determined on
a gas chromatography with FID detector (PE Auto System XL) with auto sampler
and Ezchrom integration system. Carrier gas (He); ca 25 Psi-air 450 mL min-1,
Hydrogen 45 mL-split 100 mL min-1 oven temperature 200°C injector
and detector 250°C.
Digestion trials: At the end of each collection period, nutrients digestibility
were determined by the Acid Insoluble Ash (AIA) technique as described by Van
Keulen and Young (1977), to determine the digestion coefficients and the
nutritive values of the experimental rations. Feces samples were collected for
six successive days from each animal. Total Digestible Nutrients (TDN) were
calculated according to the classic equation of McDonald
et al. (1995) as follows: TDN, Percentage = digestible CP, Percentage+digestible
CF, Percentage+digestible NFE, Percentage+digestible EE, Percentage*2.25.
Blood parameters: Blood samples were collected from all the experimental
buffaloes at the end of tested period of each ration. The blood samples were
taken from the jugular vein in dry clean glasses tubes using heparin as anticoagulant
and then centrifuged for 15 min at 4000 rpm to obtain plasma. Biochemical of
blood plasma constituents was determined by using commercial kits, total protein
and creatinine as described by Tietz (1986, 1990),
albumin was determined according to Doumas et al.
(1971), blood plasma urea was determined according to Patton
and Grouch (1977). Alanin Amino Transferase (ALT) and activity of aspartate
transfearse (AST) were determined by the methods of Young
(1990). Glucose (g dL-1) was executed by using kits of Stanbio
Laboratory Inc, procedure No. 1070. (San Antonio, Texas, USA). Total lipids,
triglycerides and total Cholesterol (mg dL-1) were quantified by
using a calorimetric method by using kits of the Bio diagnostic company.
Statistical analysis: Data were analyzed using the general linear model
procedure of SAS (2000). One way ANOVA procedure used
to analyze the intake, digestibility, feed intake, milk production, fatty acids
and blood parameter data following the next model; yij = μ+Tij+Eij,
were, μ is the overall mean of yij, Tij is the treatment
effect; the Eij is the experimental error. The differences among
means were separated according to Duncans New Multiple Range Test (Duncan,
1955).
RESULTS AND DISCUSSION
Chemical composition and fiber fractions of the experimental rations: The
chemical analysis of tested feedstuffs (Table 1) indicated
that both tested roughage (berseem and corn silage) considered as a high quality
forage which contain reasonable amounts of nutrients. Corn silage contained
more DM, OM, CF and NFE, while fresh Berseem contained more CP and ash contents.
Concerning the composition of calculating experimental rations, results showed
that all tested rations had practically nearly similar values for DM, EE, NFE,
ash and hemicelluloses. R2 and R3 showed the highest DM, CF, NDF, ADF, ADL and
cellulose. While R1 and R2 contained fresh berseem had the highest CP content
being; 15.16 and 13.94%, respectively. Such results are mainly a reflection
of the chemical composition of CFM and both kinds of tested forages.
Digestion coefficient and nutritive values: Digestibility coefficients
and nutritive values of the experimental rations are shown in Table
2. The digestibility coefficients of DM, CP, CF and cellulose were significantly
(p<0.05) higher for R1 compared to other tested rations (R2 and R3). However,
no significant differences noticed among three tested rations for OM, EE, NFE,
NDF, ADF and hemicelluloses.
In general the higher digestibility values obtained of most nutrients of all
tested rations may be attributed to the effect feeding such high quality forage
(Berseem or corn silage) which provided stimulatory factors to cellulotic bacteria
and other rumen bacteria. These factors resulted in some changes in the digestive
function which lead to increase the availability and utilization of nutrients
in the rumen and could have a significant impact on digestion and nutritive
values of experimental rations.
Data in Table 2 reported that all experimental rations had
nearly similar values of TDN with insignificant differences between tested rations.
On the other hand, R3 had significantly (p<0.05) lower DCP (8.63%) followed
by the 2nd ration (10.25), while the 1st ration (R1) had significantly (p<0.05)
higher value (11.81%). This may be due to the higher CP content of berseem than
corn silage used during formulation R1 and R2 (Table 1). The
chemical composition of grass and legumes are distinctively different. Crude
protein content is generally lower for grass than legumes; however, the composition
of the crude protein differs.
Table 1: |
Chemical composition and fiber fractions of the experimental
foodstuffs and rations consumed by lactating buffaloes (% on a DM basis) |
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B: Berseem, CS: Corn silage, CFM: Concentrate feed mixtures,
R1: B+CFM, R2: BCS+CFM, R3: CS+CFM |
Table 2: |
Digestibility and nutritive value of the experimental rations
consumed by lactating buffaloes |
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Means in the same row with different superscript are significantly
different (p<0.05), R1: B+CFM, R2: BCS+CFM, R3: CS+CFM |
Table 3: |
Effect of experimental rations on milk yield and its composition |
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Means in the same row with different superscript are significantly
different (p<0.05). R1: B+CFM, R2: BCS+CFM, R3: CS+CFM |
Grass contain more none protein nitrogen in soluble protein and legumes contain
more amino acids or peptide in soluble protein (Glenn et
al., 1989). Generally, the present nutritive values are mainly associated
with the chemical composition and proportion of the experimental feedstuffs,
in particular of berseem and corn silage. These results are in agreement with
those obtained by El-Ready (2000), El-Aidy
(2003) and Khalafalla et al. (2007) who
found a higher digestibility of all nutrients for cows or buffaloes fed rations
contained corn silage, berseem or corn silage and berseem along CFM.
Milk production and composition: The effect of feeding tested rations
on the average of actual and 7% FCM yield of the experimental lactating buffaloes
are shown in Table 3. Results indicated that, no significant
differences among tested groups in both actual and 7% FCM yields. However, feeding
experimental buffaloes rations contained either fresh Berseem (R1) or corn silage
(R3) or both tested forages (R2) did not affect such these parameters. These
results revealed also that, the requirements of the expected production of the
experimental buffaloes were covered by given formulated rations. Moreover, all
experimental buffaloes fed these tested rations achieved and maintained higher
milk production as the results of feeding such high quality forage along with
CFM in proper amounts and proportions. Similar results were found by El-Aidy
(2003) who noticed that milk yield of buffaloes did not significantly affected
by the partial replacement of berseem by corn silage.
In addition, there were insignificant (p<0.05) differences among animals
fed all tested rations in lactose, ash and SNF of milk. While feeding both kinds
of forage and CFM (R2) was significantly increased the content of milk fat,
protein and TS (7.78, 3.56 and 17.90%, respectively) compared to feeding corn
silage and CFM (R3). Meantime, no significant (p<0.05) differences were observed
in fat and protein content of milk among buffaloes fed R1 and R3. The concentration
of lactose, minerals and the other solids constituent of milk, do not respond
predictably to adjustment in diet (Varga and Ishler, 2007),
which occurred in this study.
The high fat content of milk produced by the buffaloes fed R1 and R2 may be
related to inclusion long fresh berseem in these two rations, while the lower
content of milk produced by feeding corn silage in the 3rd ration may be attributed
to the small particle length of corn silage and fine grinding of CFM used during
formulation (R3). Feeding of forages that are ground finely results in rumen
fermentation that produces a higher proportion of propionic acid and, in turn,
reduced milk fat percentage. Length of forage is an indicator of its effectiveness
in maintaining milk fat percentage. An average forage particle length of 0.25
inches or more is needed to keep ruminal molar percentage of propionate below
25 and milk fat 3.6% in cows milk (Bachman, 1992).
Milk fat percentage of cows fed corn silage based diets with 24% NDF was less
than that of cows fed 29 or 35% NDF (Cummins, 1992)
but in another study (Bal et al., 1997) production
of milk fat and milk was not different among cows fed corn silage based diets
with 25 or 29% NDF. Corn silage elicits similar or greater chewing activity
by cows than does Alfa Alfa (Mertens, 1997) and mean
NDF digestibility is similar for corn and Alfa Alfa silages (Kung
et al., 1992); therefore, the minimum amount of NDF needed to maintain
ruminal function when diets are based on corn silage is probably similar to
that for diets based on Alfa Alfa diets based on Alfa Alfa silage assuming the
particle size is adequate. While, Roseler et al.
(1997) showed that, in models for practicing DMI of lactating cows fed high
energy diets ranging in NDF from 25 to 42% of DM less than 1% of variation in
DMI was accounted for by dietary NDF. Although there are great variations were
observed the optimum values of NDF contents needed to maintain and enhance milk
composition of lactating cows as mentioned previously and by NRC
(2001) for dairy cattle. Although, the NDF and ADF values were recorded
in this study which ranged between 33.22 and 45.44% for NDF and 24.04 and 34.59%
for ADF and hence that fed intake of these nutrients, the milk composition produced
by the experimental buffaloes fed tested rations were within the normal range
of high quality buffaloes milk, which had fat, protein, SNF, TS, lactose and
ash %, not below than 7.04, 3.41, 9.73, 16.77, 5.19 and 1.15%. These results
may be explained by the fact which, indicated that, the micrflora of buffaloes
rumen were more efficient in degradation of plant tissue than that of cows as
explained by the results obtained by Bendary et al.
(2002) and Bahira et al. (2002), indicated
that DM, CF fractions and nutrients disappearance percentage of some synthetic
and natural cellulosic materials were more pronounced when samples were incubated
in buffaloes rumen than in cow rumen.
The results of the protein percentage (Table 1) indicated
that R2 had the highest value (3.65%) followed by R1 (3.56%) with insignificant
differences, while the 3rd ration recorded the lowest value (3.41%) with significant
(p<0. 05) differences.
The high protein content of milk produced by feeding R1 and R2 compared to
feeding R3 may be due to the higher TDN consumed by the buffaloes fed these
rations compared to those fed R3 ration as shown in Table 6.
Energy intake is the primary nutritional factor affects milk protein percentage
and yield. As intake of energy from carbohydrate sources increases, milk yield
and protein percentage increase and contribute, in about 85:15 proportion, to
the observed increase in yield of milk protein. Energy intake as dependent upon
DMI and energy density of the diet (Bachman, 1992). Varga
and Ishler (2007) indicated that energy is needed for maintaining milk protein
production. In early lactation, increased energy seems to stimulate both milk
and milk protein production with little effect on the percentage of protein
in milk. Later in lactation, energy does increase the concentration of protein
in milk to a certain extent. Some of this response in milk protein may be due
to the extra glucose and acetate available at the udder but added energy may
importantly cause an increase in microbial protein synthesis that increase amino
acid supply at the udder. Studies have shown that feeding more rumen available
carbohydrate can increase milk protein production.
Generally, milk composition produced by the experimental buffaloes was within
the normal range of buffalo's milk produced under similar conditions (El-Aidy,
2003).
Fatty acids profile: Fatty acid composition of milk fat is depicted
in Table 4. Generally results indicated that short chain fatty
acids (from C6:0 to C16: 1 ω) were significantly higher with ration contained
Berseem plus CFM. On contrast, long chain fatty acids (C≥18)were significantly
higher (p<0.05) with rations containing corn silage. Olic C18: 1ω9 had
a higher value being; 25.26% with R3 compared to other rations. No significant
differences observed in vaccinic acid percentage among tested rations. R2 appeared
high significant effect on linolic and linolenic contents of milk fat comoared
to rations contained Berseem or silage only.
Table 4: |
Effect of experimental raions on milk fatty acids profil |
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Means in the same row with different superscript are significantly
different (p<0.05). R1: B+CFM, R2: BCS+CFM, R3: CS+CFM |
Table 5: |
Blood constituents of lactating buffaloes fed the experimental
rations |
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Means in the same row with different superscript are significantly
different (p<0.05), R1: B+CFM, R2: BCS+CFM, R3: CS+CFM |
Table 6: |
Feed intake, feed conversion of the experimental rations |
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Means in the same row with different superscript are significantly
different (p<0.05), R1: B+CFM, R2: BCS+CFM, R3: CS+CFM |
These results investigated that fatty acids profile of buffaloes milk could
be mainapulate by using two type of green forage together (grass and legumes).
Blood constituents: Blood plasma constituents of experimental lactating
buffaloes as affected by partial or complete substitution of complete berseem
with corn silage are summarized in Table 5. Results of all
blood plasma conistuents cleared that no significant differences were observed
among the tested groups. Generally, in the present study blood parameters values
measured were within the normal range for healthy lactating buffaloes as recorded
by many authors, El-Aidy (2003) and Eweedah
et al. (2007), when lactating buffaloes fed rations containing different
roughages. They found that, globulin values ranged from 4.00 to 4.61 g dL-1,
total lipids from 378.80 to 622.10 mg dL-1, ceritainen from 1 to
2 mg dL-1. Wide variation is noticed among reviewed values, which
may be due to the plan of nutrition, kinds of feedstuffs used in feeding, age
and status of animals (lactation, pregnancy, etc.) along with the differences
in the technique adopted for estimating the plasma constituents.
Feed intake and feed conversion: Average daily feed intake by lactating
buffaloes are presented in Table 6. Buffaloes fed R2 recorded
the highst DM and TDN followed by R1, while those fed R3 showed the lowest intake
(p<0.05). The higest feed intake of DCP was recorded for animals fed R1 followed
by feeding R2, while the animals fed R3 consumed the lowest amounts DCP head/day.
This was attributed to the high content of DCP as results of incorption Berseem
in these rations (Table 2).
Data on feed conversion expressed as DM, TDN and DCP required producing one
kg 7% FCM are presented in Table 6. The production efficiency
expressed as the amount of 7% FCM produced by one kg TDN consumed by R3 tended
to be lower than other incorporation of CFM compared to feeding Berseem or corn
silage with CFM (R1 and R2). From a statistical point of view, the differences
among all tested groups were not significant. While highly significant difference
among treatment were detected concerning DCP efficiency. The better efficiency
of feed utilization obtained with the combination of corn silage and concentrate
feed mixture (R3) observed in this study is in agreement with El-Aidy
(2003) who found that lactating buffaloes fed corn silage along with CFM
were more efficient concerning the amount of 7% FCM produced by one kg DM and
TDN consumed if compared to feeding berseem and CFM.
CONCLUSION
The present results indicated that using such high quality forage for feeding
lactating buffaloes formulated balanced rations with adequate protein and energy
that reflect on health conditions and enhanced milk production and composition.
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