Productive and Reproductive Traits of Sheep Fed Acacia saligna Leaves-Based Diets

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International Journal of Environment, Agriculture and Biotechnology (IJEAB) Vol-2, Issue-6, Nov-Dec- 2017
http://dx.doi.org/10.22161/ijeab/2.6.9 ISSN: 2456-1878
www.ijeab.com Page | 2829
Productive and Reproductive Traits of Sheep
Fed Acacia saligna Leaves-Based Diets
Mohamed N. El-Gendy2, Mohamed M. Anwar2, Wael G. Fahmy1, Samir Z. El-
Zarkouny1,3, Nesrin M. Hashem1, Adel N. M. Nour El-Din1, Marwa F.A. Attia1, El-Saeed
A. El-wakeel2, Moustafa M. Zeitoun1,*
1Department of Animal and Fish and Production, Faculty of Agriculture, University of Alexandria, Egypt.
2Animal Production Research Institute, Agricultural Research Center, Dokki, Giza, Egypt.
Department of Arid Land Agriculture, Faculty of Meteorology, Environment and Arid Land Agriculture, KAU, KSA
3
Abstract Investigating effects of partial (50%) or total
(100%) substitution of clover hay by tannins -rich plant
(Acacia saligna) on productive and reproductive
performance of ewe lambs was the main goal of this
study. Two experiments were cond ucted: first focusing on
digestibility and N balance using 9 Barky rams (live body
weight, 43 ± 2.5 kg) where animals were randomly
divided into 3 groups (n = 3); con trol (C), 50% Acacia
(AS50%) and 100% Acacia (AS100%); second focusing on
productive and reproductive performance of ewe-lambs
(n=18) where animals were divided into three groups
(n=6); C, AS50% and AS100%. This experiment started 2
months before mating and contin ued till weaning. Dry
matter intake decreased (P<0.05) linearly due with
treatment. The digestion coefficients of dry matter (DM),
organic matter (OM), crude protein (CP), neutral
detergent fiber (NDF) and acid detergent fiber (ADF)
were lower (P<0.05) in treated than C. The nitrogen
intake and urinary nitrogen were reduced (P<0.05) by
treatment, while fecal nitrogen increased (P<0.0%) with
treatment. No change was found in conception rates
among the three groups whereas fertility rates and
lambing rates were higher in the treated compared to the
control. AS100% reduced (P<0.05) total protein and blood
urea nitrogen (BUN) compared to other groups. No
differences in progesterone concentration were foun d
among groups . AS50% resulted in higher (P<0.05) milk
yield than other groups. Treatment decreased (P<0.0 5)
milk fat percentage, whereas didn’t change protein and
lactose. Therefore, partial replacemen t of acacia leaves
in sheep diets could be beneficial for productive and
reproductive performance.
Keywords Feed additives, digestibility, rumen
fermentation, blood metabolites, prolificacy.
I. INTRODUCTION
The major limitation to ruminant’s production in many
tropical regions is poor nutrition, which is characterized
by low nitrogen and high fiber content in native grasses
and crop residues. In Egypt, the primary constraints to
livestock production are scarcity and fluctuating quantity
and quality of the year-round feed supply. The gap
between available and required amounts of animal
feedstuffs in Egypt was estimated to be 3.5 million tons.
There are two alternative strategies to overcome the
problem of feeds shortage in Egypt. The first is to
maximize utilization of agricultural a nd industrial
byproducts and there are several studies focused on this
point. The second strategy is seeking alternative
nonconventional feed resources e.g. tannins -rich plants or
shrub legumes, which have high protein contents and are
potentially promising to overcome nutrient deficiencies.
The multipurpose trees and tannins-rich plants represent
an important fodder reserve for ruminants in periods of
feed scarcity and pla y vital role in bridging the wide gap
between supply and demand of feeds [1]. Use of these
forages in animal diets may participate in reducing the
shortage of animal feed resources, enhance the fertility
performance of animals and subsequently increase milk
and meat production in tropic regions. The shrub foliage s
already play an important role in ruminant feeding
systems in Mediterranean and many tropical
environments around the world [2- 5].
To efficiently use alternative feed resources like tannins-
rich plants, their effects on various aspects need to be
considered. This needs more research to be do ne for fair
judgment within different points of view. Therefore, the
objectives of this study were to assess effects of the
partial or total replacement of clover ha y by acacia leaves
as an alternative feed resource on the dr y matter intake,
nutrients utilization, ruminal fermentation profiles,
reproductive and productive performance of Barky sheep.
II. MATERIAL AND METHODS
This study was carried out at the Nubaria Research
Station, Animal Production Research I nstitute,
Agricultural Research Center, Ministry of Agriculture and
Land Reclamation, Dokki, (Exp.1) and the Research Farm
International Journal of Environment, Agriculture and Biotechnology (IJEAB) Vol-2, Issue-6, Nov-Dec- 2017
http://dx.doi.org/10.22161/ijeab/2.6.9 ISSN: 2456-1878
www.ijeab.com Page | 2830
of the Department of Animal and Fish Production,
Faculty of Agriculture, University of Alexandria (Exp. 2),
Egypt. Two experiments were designed to investigate the
potential replace ment of clover (Trifolium alexandrina)
hay by acacia (Acacia saligna, AS) leaves either partially
(50%, AS50%) or totally (100%, AS100%). First experiment
was designed to investigate digestibilty and nitrogen
balance trial. However, the second experiment focu sed on
the productive and reproductive performance of ewe-
lambs.
Acacia samples collection
Acacia leaves were collected weekly during b oth
experimental periods in order to offer as fresh materials
for animals. Extra samples of acacia leaves were collected
monthly during a year to analyze total phenols (TP), total
tannins (TT) and condensed tannin (CT). The collection
region was located at latitude
of 30.91and longitude: 29.68. The region climate was
semi-arid Mediterranean climate, which is characterized
by a brief mild and rainy winter and long warm s ummer
months with no rain. The chemical composition and
tannins content of the commercial concentrate mixture,
clover ha y a nd acacia leaves for b oth e xperiments are
presented in Table 1.
Table.1: Chemical composition and tannins content of the concentrate mixture, clover hay and Acacia leaves
(Based on dry matter)
Item (%)
Concentrate
Clover hay
Acacia leaves
OM
88.5
89.3
89.6
CP
14.1
12.5
13.2
EE
5.8
1.0
4.8
NDF
38.3
64.2
64.9
ADF
10.6
55.8
60.6
Tannins content
TP*
-
10.2
42.1
TT*
-
1.6
27.1
CT**
-
2.0
72.0
OM: Organic matter, CP: Crude protein, EE: Ether extract, NDF: Neutral detergent fiber, ADF: Acid detergent fiber. *TP:
total phenols (eq-g tannic acid kg-1DM), *TT: total tannins (eq-g tannic acid kg-1DM), **CT: condensed tannins (eq-g
leucocyanidin kg-1DM).
Experiment 1
Animals and experimental design
Nine mature Barky rams (mean live body weight 43±2.5
kg) were randomly divided into three equal groups (n = 3)
as control (C), AS50% and AS100% according to live body
weight. Animals were housed in well-ventilated shade and
adapted to the treatment feeds for 4 weeks before being
subjected to the digestibility trial and had free access to
fresh water. The animals were fed in groups on a
commercial co ncentrate feed mixture and roughages
according to NRC [6]. The acacia leaves were offered
fresh daily as partial or total replacement to the clover hay
by 1.0 kg and 2.0 kg/h/d, respectively, while the clover
hay was offered to the control and partial replacement
group by 1.0 and 0.5kg/h/d, respectively. The co mmercial
concentrate feed mixture was offered to all groups by 0.75
kg/h/d for all groups. After familiarization to the diets, the
animals were kept in metabolic cages for 8 days of which
3 days for adaptation and 5 days for samples collection.
Experimental animals were offered concentrate and
roughages individually in buckets twice daily at 8:00 and
14:00 hr. During the collection period, animals were
individually kept in metabolic cages and feed refusals,
feces and urine were collected for the purpose of
measuring nutrients digestibility and N balance.
To measure apparent total tract nutrients digestibility, two
representative samples of feces 10 % of the total quantity)
were collected daily from each animal; one of the two
samples was sprayed with citric acid (10%) and stored
under -20C, the second was used for determination of the
feces DM. Immediately, at the end of collection period
stored feces samples during 5 days for each animal were
pooled, mixed well and a sample was obtained for further
analyses. Representative portions of fece s were dried in a
forced air-oven at 50°C for 48 h and then ground to pass
through a 1 mm-screen and stored at -20°C thereafter
until analysis.
The urine was collected daily throughout the collection
period in plastic buckets containing 100 mL of H2SO4
(10%). Also, representative samples (10% of total
volume) were collected daily from each animal and kept
in dark bottles. At the end of collection period, urine
samples from each a nimal were mixed well and obtained
a sample, which kept under -20C until a nalysis. Upon
analysis, thawed uri ne samples were centrifuged at 2000
rpm for 20 min and sub-samples were analyzed for
International Journal of Environment, Agriculture and Biotechnology (IJEAB) Vol-2, Issue-6, Nov-Dec- 2017
http://dx.doi.org/10.22161/ijeab/2.6.9 ISSN: 2456-1878
www.ijeab.com Page | 2831
Kjeldahl N [7]. Ruminal fluid samples were obtained
from each animal via a stomach tube before morning
feeding for two consecutive days. The ruminal fluid
samples were separated from the feed particles through
four layers of cloth sheets and then stored under -20oC for
VFA and ammonia N analyses.
Experiment 2
Animals and experimental design
Eighteen ewe-lambs (li ve body weight of 35±2.5 kg and
age of 10 months) were divided into three equal groups
(n=6) according to the body weight; control (C), AS50%
and AS100% to study the reproductive and productive
performance. Ewe-lambs were fed on a co mmercial
concentrate feed mixture, clover hay and acacia leaves
according to NRC [6]. The acacia leaves were collected
and offered fresh daily. The Alexandria University
guideline for the ethics and use of experimental animals
was approved.
Reproductive performance of ewe-lambs
This study was started two months before mating and
continued till lambing. T he control ewe-lambs were fed
on a commercial concentrates feed mixture and clover hay
(1.0 kg/h/d). The AS50% animals were fed a co mmercial
concentrate feed mixture and clover hay (0.5 kg/h/d) and
acacia leaves (1.0 kg/h/d). The AS100% animals were fed a
commercial concentrate feed mixture and acacia leaves
(2.0 kg/h/d).
Ewe-lambs were fed the commercial concentrate mixture
in groups, hay and acacia leaves in about two equal parts
at 8:00 and 14:00 hr daily. The ewe-lambs had free access
to fresh water through the experimental period. Blood
samples were collected every mo nth from the jugular
vein, before access to feed and water in test tube without
anti-coagulant. The samples were centrifuged at 3000 rpm
for 20 min to get the serum for biochemical parameters
assay. T otal protein and albumin were assayed by
colorimetric kits (Stanbio, Boerne, Texas, USA). Glucose
was assayed using colorimetric kits (Futura System,
Formello, Rome, Italy) and blood urea nitrogen (BUN),
creatinine and cholesterol were assayed by colorimetric
kits (BioSystems, Costa Brava, Barcelona, Spain).
Globulin concentration was calculated as the difference
between total protein and albumin.
After two months of the beginning of the experiment, all
ewe-lambs were injected with prostaglandin PGF (0.5
ml of estroPLAN with the concentration of 125 μg
Cloprostenol; Par nell Technologies, Alexandria, New
South Wales, Australia). The animals were submitted to
estrus detection twice daily using mature teaser ram at
7.00 and 19.00 hr for 3 days, ewe-lambs which were
mounted by teaser rams, were mated by fertile rams. The
ewe-lambs which was insensitive to the effects of first
PGFreceived a second injection of PGF (0.5 ml of
estroPLAN with the concentration o f 125 μg
Cloprostenol) after 12 days from the first injection then
submitted to estrus detection twice daily using mature
teaser ram at 7.00 and 19.00 hr for 3 days. Ewe-lambs
which were mounted by teaser rams were mated by fertile
rams. A blood sample was taken from each ewe-lamb at
the days of i njection, estrus, 5, 10 and 20 after estrus for
determination of BUN and progesterone.
Productive performance of ewes
Birth weight of the neonates were recorded at the day of
birth and their weaning weights were recorded when
lambs reached the age of 4 months. Daily weight gain of
lambs was calculated using weekly body weight for each
lamb.
Milk production was measured weekly postpartum and
for seventeen weeks (119 day). Daily milk yield for each
ewe was p erformed using weigh suckle-weigh technique
[8]. Lambs were separated from their dams at 14:00 hr the
day before milking and in the day after. The lambs were
weighed at 6:00 hr and left to suckle their dams till
satisfactions. They were weighed again and kept in closed
pens till next milking at 14:00 hr. In the meantime their
dams were striped to estimate the stripping milk. The
same procedure was followed again at 14:00 hr in the
same day. The daily milk yield was calculated by
summing the weight of suckled milk (differences between
lamb's weight before and after suckling) and the weight of
striped milk in both morning and afternoon milking. Milk
production was evaluated using a graduated cylinder (±5
mL). The amount of milk obtained was adjusted for 24 hr
on weekly basis. Milk samples (100 mL) from individual
ewes were taken for proximate analysis using Milk
Analyzer (Milko Tester Instruments Inc., Bulgaria).
Milk urea nitrogen (MUN) was deter mined by adding 2
mL trichloroacetic acid (10%) to 5mL of milk sample for
protein precipitation and left for 30 min then the mi xture
was centrifuged at 3000 r pm for 20 min in order to
separate the supernatant which was used to determine
milk urea nitrogen b y colorimetric method (Stanbio,
Boerne, Texas, USA) [7].
Blood samples were collected ever y month until the end
of the experiment from the jugular vein, before access to
feed and water in te st tube without anti-coagulant to get
coagulated blood samples. The samples were centrifuged
at 3000 rpm for 20 min an d sera were harvested for
biochemical assays.
Samples analysis
The dry matter (DM) of feed and feces were analyzed by
drying at 105C for 24 h. The AOAC (2006) analytical
procedures were used for the organic matter (OM)
determination (No. 968.08) by ashing at 600 C for 2 h, N
estimation (No. 988.05) by a Kjeldahl technique and ether