ABSTRACT
Two experiments were conducted at the piggery unit of the
Department of Animal Science Farm, University of Nigeria, Nsukka from June 2010
– September 2011, to determine the effect of dietary supplementation with
vitamins E and C on the productive performance of pigs. The first experiment
assessed the effect of dietary combinations of different levels of vitamins E
and C on the growth performance of weaner pigs. Thirty six, Eight weeks old
weaner gilts were used for this trial. They were randomly assigned to nine
experimental treatment diets having different combinations of vitamins E and C
(0 mg vitamin C/0 iu vitamin E (T1), 250 mg vitamin C/0 iu vitamin E
(T2), 500 mg vitamin C/ 0 iu vitamin E (T3), 60 iu
vitamin E/0 mg vitamin C (T4), 60 iu vitamin E/250 mg vitamin C (T5),
60 iu vitamin E/500 mg vitamin C (T6), 120 iu vitamin E/0 mg vitamin
C (T7), 120 iu vitamin E/250 mg vitamin C (T8), 120 iu
vitamin E/500 mg vitamin C (T9) with four gilts per treatment. The
gilts were housed in pairs making up two replicates per treatment. The initial
body weights and linear body measurements of the gilts were recorded before the
start of the experiment. Thereafter, weekly body weights and linear body
measurements were taken and continued till the gilts attained puberty at the
age of 5 months. One experimental diet with 18% crude protein (CP) and 2800
kcal/kgME was formulated for the gilts in the nine treatments but had different
levels of vitamins E and C assigned to each treatment. The vitamins were
administered through the feed at the time of feeding. In experiment 2, sixteen
gilts were selected out of 36 gilts from experiment 1 and randomly assigned to
four dietary treatments to evaluate the effects of the combinations of vitamins
E and C on the reproductive performance of gilts. Each treatment was replicated
twice with two gilts per replicate making up four gilts per treatment. One
experimental ration containing 15% CP and 2500kcal/kgME was used but different
levels of vitamins E and C for each treatment were added to the feed at the
time of feeding. The gilts were placed on the gestation/lactation diet
immediately after selection and were allowed to attain their second estrus
before mating took place. The body weight of the gilts were recorded before
mating following the manifestation of second estrus and date of mating recorded.
Gilts were fed 2.0kg of 15% CP diet each day when pregnancy was confirmed.
Weekly body weights of the gilts were subsequently taken throughout the
gestation period. At farrowing, their ration was increased to 2.6kg per pig per
day until piglets were weaned at the age of 8 weeks. The birth weights of the
piglets were recorded within 24 hours of parturition, and subsequently piglet
weekly body weights were recorded until weaning. Similarly, the body weights of
the lactating sows were taken weekly to monitor their body weight changes
during lactation. All the data in both experiments one and two were processed
and analyzed in accordance with 3 x 3 and 2 x 2 factorial arrangement,
respectively in a completely randomized design (CRD). Results of experiment one
showed a significant (P<0.05) interaction of vitamins E and C on the body
weight of gilts. Weaner pigs on T5 diet containing 60iu and 250mg of
vitamins E and C, performed significantly better (P<0.05) in terms of
average final body weight (66.13 ± 2.49kg) and growth rate (633.50 ±
30.34g/day) than those in other treatments. However, feed intake and feed
conversion ratio were comparable (P>0.05) among the nine treatments. There
were significant differences (P<0.05) in flank-to-flank lengths among the
gilts in the treatments, with T1 and T2 having the
highest values of 67.13 ± 1.82cm and 67.25 ± 1.23cm, respectively. Gilts on T5
had the highest (P<0.05) heart girth values of 83.68 ±
1.22cm, while gilts on T8 and T9 had comparable but lower
heart girth of 65.08 ±1.42cm and 65.00 ± 1.06cm, respectively. Significant
interaction (P<0.05) effects of vitamins E and C were observed in body
weight, weight gain, flank-to-flank and heart girth measurements of gilts at
puberty. In the reproductive phase, average litter size values of 7.00 ± 0.58,
8.00 ± 0.41, 8.00 ± 0.00 and 7.00 ± 1.00 for T1, T2, T3
and T4, respectively and the corresponding birth weight mean values
of 0.97 ± 0.08kg, 1.05 ± 0.11kg, 1.19 ± 0.00kg and 1.24 ± 0.03kg were not
significantly different (P>0.05) among the treatments. Significantly lower
(P<0.05) pre-weaning body weight gain (g/day/piglet) was observed for
piglets on T1 with mean value of 126.25 ± 5.62 compared to piglets
on T2, T3 and T4 with respective values of
150.77 ± 5.00, 150.51 ± 1.59 and 164.12 ± 7.23. A range of 22.07 ± 3.45% to
25.10 ± 0.10% pre-weaning mortality was observed across treatments. Piglets on
T1 had the least weaning weight of 7.25 ± 0.28kg which differed
significantly (P <0.05) from piglets on T2, T3 and T4
with weaning weights of 8.42 ± 0.24kg, 8.62 ± 0.08kg and 8.71 ± 0.60kg,
respectively. The highest (P <0.05) gestation weight gain of 50.20 ± 0.20kg
was recorded for gilts on T3 while the least (P <0.05) gestation
weight gain of 44.33
± 4.48kg was observed in gilts on T1.
This study finally suggested that a combination of 60 iu
vitamin E/250 mg vitamin C, and supplementation of 120 iu vitamin E alone are more suitable
for the improvement of growth performance of pigs managed intensively, while dietary
vitamins E and C supplementation at 0 iu vitamin E/250 mg vitamin C, 120
iu vitamin E/0 mg vitamin C and 120 iu vitamin E/250 mg vitamin C
combinations during gestation of gilts and their lactation will effectively
enhance litter size
and lactation performance.
CHAPTER
ONE
1.0 INTRODUCTION
Meat is becoming a highly scarce commodity especially at a
time when staples like garri, cowpea and rice can not be reached by many
consumers as a result of the global food crisis which is currently plaguing the
country as well as many other countries in the world.
Due to the expensive nature of poultry meat and egg, beef,
mutton, pork, chevron etc, people now have resorted to frozen fish consumption
which was ignored years ago. Shortage of protein particularly those of animal
origin, is prevalent, not only in Nigeria but also in most parts of Africa,
where it is estimated that on the average, 10g of animal protein is consumed
per day per person, compared to a recommended daily intake of 35g (ILCA,
1980).The level of consumption of meat and animal protein in Nigeria is
estimated at about 8g per caput per day, about 27g less than the minimum
requirement by the National Research Council of the United State of America.
Despite the progress made in pig production, current production levels
especially in the developing countries are still less than the biological
potentials of pigs.
Pig production in Nigeria
today, has been adversely affected by a number of factors, which can be traced
to environmental, nutritional, management and perhaps, genetic factors. When a
stock with high genetic potential is in place, these other factors need to be
totally controlled before high production will be achieved. Controlling these,
will impact positively on the animals’ overall productivity.
Again, the fear created by the emergence of avian influenza
(avian flu) has negatively affected animal protein intake of Nigerians. The
large number of backyard household poultry enterprises have reduced due to the
dread of the ominous consequences of the avian flu outbreak. This has therefore
kept poultry products out of the reach of the poor urban and rural dwellers.
Pig production therefore, seems to be the likeliest and
quickest means of solving the problem of insufficient animal protein intake,
especially in the Southern and Middle-Belt zones of Nigeria, where pork is not
discriminated against.
Also, considering the sustained pressure on livestock
producers to reduce environmental impacts and optimize animal welfare, the on-going
pursuit of advances in nutrition of which this research is part of, will be
fundamental to the sustainability of pig production. Pig and poultry unlike
ruminants, according to Preston (1990) do not produce methane and therefore are
regarded as being environmentally friendly.
Among the factors that militate against animal performance,
biological free radicals have been strongly implicated as one of the major
causes of poor performance and low productivity in a high intensive animal
production. In the event of the failure of the tissue antioxidant defense
system to stabilize the activities of the free radicals, which have potentially
detrimental effects on animal performance and are highly reactive, these
continue to be generated leading to tissue and cell destructions. This will
have very negative effects on the productive potential of the animals.
Therefore, delivery of supplemental antioxidant vitamins to domestic animals in
confinement might improve health and performance outcomes by reducing the effects
of oxidative stress to which these animals are presumably exposed. The health
outcome of morbidity and the production outcomes of weight gain and feed
conversion ratio, are expected to be improved.
Supplementation with levels of feed additives has been used
in swine feeds since 1950’s for improved growth rate and feed efficiency and to
maintain pig performance. The most effective use is in the diets of weanlings
and young growing pigs, but good responses are also obtained in finisher and
breeding swine (Zimmerman, 1986)......
================================================================
Item Type: Ph.D Material | Attribute: 136 pages | Chapters: 1-5
Format: MS Word | Price: N3,000 | Delivery: Within 30Mins.
================================================================
No comments:
Post a Comment