Fazenda Paineiras da Ingaí -
Búfalos Murrah Leiteiros
of nutritional requirements is only one of the factors that can influence the
reproductive activity of the buffalo cow, which does yet show a lactiferous
habit. Nutritional effects on reproductive performances give results that depend
on the sanitary conditions in which the buffalo lives and on the breeder’s
managerial abilities. The nutrition effects on the reproductive performances are
more evident in those countries where buffaloes calve during the most favourable
periods for their ovarian cyclic activity and where forage availability depends
on climate. In those countries where the calving calendar has to be modified for
commercial reasons, dietary errors increase the negative effects determined by
the atmospheric conditions.
modification of nutritional levels, which in many cases is responsible for a
cyclic activity break in young subjects and in those in lactation, is a very
important factor. Nutritional errors during the dry milk period may worsen
reproductive performances affecting, in turn, normal energetic balance,
immediately after calving, and mineral equilibrium. Consequently an alteration
of the normal endocrine-metabolic state is found, which is necessary for the
ready recovery of reproductive activity.
this present study, the various effects that diet can have on buffaloes as
opposed to milk cows is highlighted.
buffalo, nutrition, reproductive performances
zootechnics the optimization of production depends on the quick restoration of
reproductive activity immediately after calving and/or the anticipation of
puberty in subjects destined to the culling. These conditions help to reduce the
herd’s unproductive period knocking down production costs within the last
decades, have rocketed in industrialized countries. Moreover, the anticipation
of puberty shortens the generational interval favours genetic improvement.
Various factors influence reproductive activity, in particular pathologies, farm
management, climatic conditions, space availability and nutrition. They may play
a direct or an indirect role but
they always modify the reproductive characteristics of the zootechnical species.
The reactions of the single species to the above mentioned factors are always
very evident; and whereas environment has a
greater influence on the photoperiodic species, nutrition plays a very important
role in the species with a high productive specialization for which it has
become more and more difficult to meet the productive requirements and reduce
the energetic gap at the beginning of lactation. Anyway, generally the factors
listed above interact and strengthen the negative effects that influence the
subject’s productive and reproductive activity.
the present work we will consider the effects of nutrition on buffalo
reproductive activity and their possible interactions with
climatic conditions and farm management; therefore we will illustrate the
characteristics that a correct diet
should have in the various reproductive phases paying particular attention to
the dairy buffalo diet.
buffalo is a photoperiodic species.
Like sheep, buffaloes have to be considered a "short day" species.
They have heats throughout the year
but tend to result more fertile when day light hours decrease. According to
Zicarelli (1995) this characteristic is due to their tropical origins. They come
from North equatorial areas where the availability of forage coincides with the
period in which the dark hours increase. Therefore, it has been supposed, that
animals which calve in the most suitable period for survival of the offspring,
were selected. It seems that they kept this characteristic even when they were
transferred to places where forage is always available (Zicarelli, 1995). In
countries like Italy, where market demand requires more calvings in the
spring-summer period (not in keeping with this species reproductive activity)
the out of season technique is largely applied. Thanks to this buffaloes less
sensitive to photoperiodic effects were selected. Where the out of season
technique has been applied for long periods there is a lower loss of fertility
(15% vs 30%) compared to the farms where it has been adopted for shorter
periods. These results are also due to the renewal of the herd
that is very frequent in those farms that apply the out of
breeding season technique. It
is known that after their 5th calving, buffaloes decrease production during the
270 lactation days. They may have relaxation of the pelvic girdle and a delayed
uterine involution, probably due to
an altered mineral exchange. This situation creates an uterine environment
unfavourable to conception and it worsens the herd reproductive performances.
Moreover the season-dependant reproduction
phenomenon is more frequent in older buffaloes (Zicarelli et al., 1988) that
feel the bull effect more and they meet the season
aciclia phenomenon more easily. In studies carried out on Mediterranean
buffaloes bred in Italy it resulted that melatonin represents the light/dark
alternation endocrine sign. The elevation of the melatonin plasma levels, 2
hours after sunset, is much lower in less
photoperiod-sensitive subjects (Di Palo et al., 1993; Parmeggiani and Di Palo,
1994). The high repeatability of this character leads us to
suppose that it may be a
hereditary character, very useful for genetic aims.
Matter Intake and Feeding Behaviour
The productive increase registered in some Italian herds or the lack of
optimal forage may be the cause of imbalances
between animal intakes and requirements for milk and/or meat production. This
situation has negative effects on the subject’s productive and reproductive
In buffaloes, as in other domestic ruminants, the dry matter intake (DMI)
depends on different factors related to the chemical composition of the diet, to
the organoleptic characteristics, to the storage conditions of the food, to the
presence of chemical contaminations, to the animal’s physiological condition,
to its age, sex and reproductive specialization and, finally, to its productive
The content in the cellular walls (ADF, NDF, ADL), and the energetic and
proteic density of the diet may
influence the ingestion of DM. The increase of fibrous fractions (Mudgal, 1988)
and of proteic concentration (Campanile et al., 1997b)
determines a lower DMI, while the increase of the energetic density of the diet
(Mudgal, 1988) has a contrary effect. This last affirmation is true in
developing countries but in Italy,
where diets are composed of energetic concentrations ranging between 0.88 MFU
and 0.94 MFU per DM Kg, a further increase could determine effects that
contradict the results reported by Indian researchers. This effect could enlarge
if the raising of the energetic
level is obtained with highly
fermentable feed. An energetic or proteic excess, in fact, increases glycemia
which exerts a negative feed-back on the appetite through endocrine-metabolic
The ingestion of DM, referred to the metabolic weight (W0.75), increases according to the age of the
subject. Voluntary intake ranged between 1.6% and 2.2% of live weight have been
noticed in growing subjects (Ranjhan
, 1992); Tabaria and Sharma (1980) have observed
that in heifers weighing 220
- 240 kg LW, voluntary ingestion ranged from 56 to 76g/kg W0.75.
Italian authors (Moniello et al. 1992) have recorded intake of DM equal to
109g/kg W0.75 in
Mediterranean race castrated males bred in Italy (live weight equal to about 360
kg). Mudgal (1988) carried out a
study on Murrah buffaloes from which
it results that they intake about 68g/kg W0.75 in dry period and
137 g/kgW0.75 during
lactation. In Mediterranean buffaloes the DMI ranges from 112 to 137g/kg W0.75 (Verna
et al. 1992/1994), showing fluctuations
between 102 and 164g/kg P0.75 according to the open period, to the
productive level and to the dietary
characteristics (Campanile et al., 1997a).
In the last two months of lactation there is a lower
DMI ( 93- 104 g/kg W0.75)
(Campanile et al., 1996). In all the experiments mentioned above the
intake resulted conditioned negatively by the content in the cellular walls (ADF,
NDF, ADL) and positively by milk production. In recent studies concerning
buffalo feeding behaviour during lactation, it has resulted that the
DM average intake, reduced by the dose required for maintenance, is equal
to 275g per Kg of equivalent corrected milk (Campanile
et al., 1977b).
of Nutrient Lack/Excess on Fertility
The energetic requirement for maintenance depends on the physiologic
conditions of the subject. According to Arora et al.(1978) in calves with live
weight equal to 70 kg the
energetic requirement for maintenance is equal to 186 kcal of ME (metabolizable
energy) /kg W0.75 and
it reaches 197 and 206 kcal ME/kg in
heifers weighing 135 and 200 kg that grow 450g/die. According to experiments
carried out on Mediterranean heifers with a starting weight of about 260 kg, the
mean daily intake of 8500 kcal of NEl
(net energy for lactation) allowed a
daily gain ranging from 636 to 742 g. It resulted higher in the subjects whose
diet was rationed according to the Unifeed technique with a
14 % proteic concentration on dry matter (Borghese et al., 1997). We have
reported analogous results in our experiments (date not published); it has
resulted that the daily gain depends on the age and body conditions of the
subject at the beginning of the
experiment. Because of the compensatory growth phenomenon the highest increases
occurred in the older and underweight heifers.
According to Mudgal and Kurar (1978) at the beginning of lactation the subjects’ requirements for maintenance result equal to 188.85 kcal of ME/kg W0.75 and more than 37% of those required in mid lactation (119.57 kcal ME/ kg W0.75; Sivaiah And Mudgal, 1978). In the dry-period, buffalo needs range from 100 to 147 kcal ME/kg W0.75. I think that the energetic maintenance requirements for buffalo during the different physiological phases may be similar to those reported by French authors for dairy cows (70 kcal NEl/ kg W0.75) and that the productive requirements, referring to standard milk/kg (4% fat content), are quite similar to those reported for dairy cows. To verify this, we have reported in the table the results obtained in experiment carried out on Mediterranean buffaloes (Verna et al., 1992/1994). Reading the data in the table it is clear that subtracting or adding the body weight loss or energetic dose accumulation to produce a kg of milk about 750 kcal of NEl are necessary.
with high or less energy (A/B)
and/or protein content (a/b):
data are confirmed by Mudgal and
Kurar (1978) who refer analogous values for the production of equivalent
corrected milk (ECM); the requirements estimated by Sivaiah
and Mudgal in the same year are quite different. They
propose 600 kcal of NEl.
evaluation of the energetic density (MFU/DM) is very important in a diet. It
varies according to the shorter buffalo calving period, responsible for the
variable inter-calving interval throughout the year.
there are herds with very highly productive subjects, the energetic density of
the diets is more and more similar to
that used for dairy cows also because the lactation period is shorter in
buffaloes than in cows (270 days vs 305 days). This means that for the same
quantity of energy produced during a lactation, the daily energetic requirements
are higher for buffaloes.
buffalo that produces 2000 kg of milk containing 8.5 % fat and 4.5% protein
(data concerning buffaloes
registered in the Italian Herd Book)
is equal to a Frisian cow that produces 3635 kg of milk containing 3.5% fat and
3.1% protein in 305 days. Using the
same energetic equivalent obtained
with formulas elaborated for cows (INRA,
1988) and buffaloes (Di Palo, 1992) we notice that buffaloes
require, during the 270 lactation days, 3032 MFU (( kg ECM x 0.44 MFU) +
(5.75 MFU (maintenance dose for loose housed) x 270 days)) and, therefore, 11.23
MFU (1 MFU = 1700 kcal NEl) a day; cows require 3233 MFU because the maintenance
requirements are estimated for 305 days and the daily needs are equal to 10.6
MFU. Since in both species the DMI amounts
to a little more than 14 Kg a day, we deduce that buffalo diets should have a
higher energetic density (0.802 MFU vs 0.757 MFU). This difference increases
with the increase of the herd’s productive level
and it will be very evident
at the beginning of lactation. Owing to these considerations,
in herds producing an average of over 2000 Kg and during the months in
which the greater part of the calvings occur, we recommend the administration of
diets containing energetic
concentrations higher than 0.9 MFU/DM. In this way there wont be
a strong mobilization of body reserves that would determine a great
weight loss with consequences on the subject’s productive and reproductive
activity. It is known that a negative energetic balance causes a reduction of
IFG1s and of insulinaemia (Gluckman et al., 1987; Lucy et al., 1992) which is a
critical condition for development (Adashi et al., 1985, Hammond et al., 1988)
and follicular growth (Lucy et al., 1992). The existence of
insulin receptors in hypothalamus
median eminence suggests a modulating action of the pancreatic hormone on the
GnRH hypothalamic output (Butler et al., 1989). This regulation could depend on
the greater quantity of energy (glucose) that insulin could guarantee to the
hypothalamic cells that determine GnRH incretion. Insulin is hormone that
regulates the metabolic activities of the various tissues by favouring the
energetic influx required for cell functionality. The lower quantity of
hypophysial LH in underfed subjects associated
with high levels of GnRH (Dunn and Moss, 1992) is proof that underfeeding has
effects mainly of the hypophisial level. I'Anson et al. (1990) have reported
that the administration of pentobarbital, a non specific neural inhibitor,
increases the number of LH pulses in underfed subjects. According to Lucy (1992)
there are negative correlations between the E2:P4 ratio in the follicular liquid
and IFG1 (lower when there is an energetic deficiency) that could affect for
follicular growth and development in diets with energetic deficiencies probably
because the LH ovarian receptors decrease (Roche and Diskin, 1995). According to
Adams et al. (1996) the elevation of GH in underfed sheep is necessary to keep
IGF1 levels with in physiologic limits but it does not have effects on the
hypophysial gonadotropins concentration and follicular growth.
increase of GH levels in nutritionally restricted ewes reduces ovarian
stimulation by gonadotropins (Suttie et al., 1991); the aim of all this is to
favour the subject’s survival through the reduction of metabolic demand (Adams
et al., 1996).
exogenous administration of GH as r-BSt in buffaloes improves the superovulatory
response increasing the number of subjects responsive to treatment with p-FSH
but it reduces the number of embryos recovered for positive flushing (Zicarelli
et al., 1994). In studies carried out on sheep Davis et al. (1990) noticed that
the administration of bGH does not increase the ovulation rate. In bovine
heifers, on the other hand, the small follicles increase (Gong et al., 1991).
(1989) reported that in buffaloes the loss
of body weight during the first 4-5
months of lactation results inversely correlated to the mating period
and to the number of services necessary for conception. Negative
correlations between the daily milk yield average
and the mating period length were reported by Zafar (1985); weight gain
during the insemination period (mostly regarding the less productive subjects)
improves fertility (Kaikini et al., 1981). As proof of a negative energetic
balance, Eltohamy et al. (1994) noticed that subjects affected with ovarian
hypoactivity had low levels of glucose and cholesterol. Here it must be
underlined that the lowering of the
glycemic levels occurs only when there are high energetic deficiencies but it
may be registered more easily when there are proteic deficiencies due to lack of
carboxylic neogluco markers. Only 10-15% of haematic glucose comes from food,
the remaining part comes from neoglucogenesis (Otchere et al., 1974).
buffaloes aged between 6 and 10 years glucose haematic levels have resulted
higher in pregnant subjects on the basis of the not-rebreeding index. Besides
negative correlations with the number of services for conceptions have been
reported (El-Belely et al., 1994).
The relation between this metabolite and milk production makes one think that in
the more productive subjects the negative energetic balance modifies normal
reproductive activity. In the Mediterranean buffalo the energetic deficit
retards ovulation by about 6 hours (Campanile et al., 1991a); this may depend on a slower LH response IGF1 mediated. Studies
carried out in Brazil demonstrate that increasing the number of head /hectare
the percentage of calvings throughout a year decreases (Baruselli, 1993). In a
study carried out on Murrah buffaloes, Arora and Kaur (1982) reported a great
reduction in the conception rate in underfed subjects (66.6% vs 16.6 %) compared
to those whose diet satisfied productive requirements.
The beginning of lactation is generally characterized by loss of body
weight because of the imbalance that occurs between ingested energy and the
energy utilized for milk production; the organism remedies to this gap through
fat mobilization that is higher than the energetic deficiency increase. The loss
of body weight (more than 10% of live weight) in the first two months of
lactation increases post-partum anestrous in the dairy cow. The ovarian cyclic
activity will start again when the subject recovers its body weight which
coincides with the elevation of insulinaemia and with the flexion of the
lactation curve. To obviate this phenomenon, at the beginning of lactation the
energetic density of the diet should be increased changing the F:C (forage:concentrates)
ratio. If this is obtained increasing the starch
dose a sub clinic metabolic acidosis condition occurs in buffalo cow. It
increases the endometritis rate, the calving-conception interval and the number
of empty subjects (Campanile et al., 1991c).
In p-FSH superovulated buffaloes, increasing of the energetic concentration with
a high starch dose reduces the number of embryos recovered for flushing (Di Palo
et al., 1994). Therefore one needs to increase the diet energetic density with
high quality forage (grazing stage of ryegrass hay silage) instead of hay and/or
with rumen protected fats.
In dairy cows the use of
calcium soaps retards the ovarian cyclic activity (Sklan et al., 1991) and
increases the number of follicles with a diameter greater than 15 mm responsible
for the increase of circulating oestrogens and embryo mortality. (Lucy et al.,
1991). Dietary rumen protected fats stimulates milk production with the increase
of mobilization of body reserves; as
proof, the levels of circulating
NEFA result increased (Sklan an coll.,
1994). This phenomenon has been registered also in buffaloes that have received
cryo-crystallized fatty acids from the
beginning of lactation (Di Palo et al., 1997). Studies in progress demonstrate
that in Mediterranean buffaloes the increase of diet
energetic density using
protected fats, reduces the calving-conception interval from 48 to 38 days (Zicarelli,
1997). The same situation occurs in beef cows. Hightshoe et al. (1994) report
that supplementing the diet with calcium soaps does not have an effect on the
cycle and on reproductive activity resumption; it favours
follicular growth, and P4 and LH haematic levels during the luteinic
phase, increases the linolenic acid that augments the PGF2
and, thus, cyclic activity starts again and the pregnancy rate increases.
Energetic deficiencies during puerperium accentuate the phenomenon of
follicle atresia that develops in the following cycles (Wright et al., 1992).
The effects of energetic deficiency may be determinant in the precalving period;
it seems that underfeeding effects weigh mainly on the preantral follicles (Britt,
1991) that need about 110 days to pass from the primordial to the preovulatory
phase (Lussier et al., 1987). Experiments carried out by Kruip et al. (1995)
quite agree with this hypothesis. Perry et al. (1991) and Selk et al. (1988)
think that the ingestion of a lower
amount of nutrients in the last quarter of gestation
influences the following reproductive activity in the post-partum period.
Optimum body conditions at calving time, valued through BCS, positively
influence reproductive efficiency through a quick restarting of the ovarian
cycle and an improvement of fertility. A quick activation of hypophosys and
higher levels of LH have been observed as proof of an efficient GnRh
hypothalamic release (Wright et al., 1990). Low energetic levels
in the pre-calving period cause a decrease of the GnRH hypothalamic
release and of the LH pulsatile
release (Proknor et al., 1986); these effects should be mediated by insulin and
by IGF1s (Lucy et al., 1992). It has been observed that in sheep too,
underfeeding could cause a lower secretion of LH and an increase of GH (Foster,
1989) that, facilitating lipolysis would preserve body proteins during loss of
weight (Hart et al., 1995; Waghorn et al., 1987). In buffaloes an optimal BCS at
calving time (
3.5 points; 1 to 5 scale) improves reproductive
efficiency (Hegazy et al., 1994; Baruselli et al., 1997) due to a shortening of
the calving/conception period and to a diminution in the number of the services/conception.
Baruselli et al. (1997) have noticed a worsening of fertility in subjects that
were very fat at calving time. They agree with Dhilon et al. (1994) that have
noticed in these subjects a quick restarting of ovarian activity, a retarded
conception and an increase in the number of services required for conception.
This should demonstrate that the excessive fat accumulation could influence the
uterine environment. As well as buffaloes, dairy cows that are very fat at
calving time present a greater incidence of retained foetal membranes and
uterine atony that retard lochia
expulsion. According to Hegazy et al. (1994) the effects of underfeeding in the
pre-calving period decrease, in buffaloes, the effects of high energetic levels
at the beginning of lactation. These last studies could explain Zicarelli’s
hypothesis (1994) according to which this species’ season-dependent
reproduction activity, connected with a negative photoperiod, is the consequence
of the adaptation of this animal, over centuries, to the
availability of forage required
to satisfy its requirements and survival. In Brazil, in
the Southern tropical and subequatorial areas, buffalo dry period occurs
when there is the greatest availability of forage; in the tropical and
subtropical areas of Asia and Africa,
forage is mostly available during the last phase of gestation.
In buffaloes, the urea levels in blood and milk reached a higher level
when a low-protein diet was given for a fairly long period of time. Decreasing
occurs when the dietary proteic concentrations from high become low, i.e. when
there is an acute stimulus (Campanile et al., 1996a).
Smith (1969) reports that in ruminants that live in tropical areas, nitrogen
deficiencies decrease the urea kidney clearance,
increase ruminal return and decrease
haematic levels. Therefore there would be better urea recycling in the digestive
trait and better ruminal bacteria proteic synthesis (Houpt, 1970).
With the same ECM value the lower quantity of proteins produced with
buffalo milk compared to the cow (31
g vs 27.1 g) allows buffaloes to use low
proteic forages (Zicarelli, 1994). This could explain the adaptation of this
species in South American countries where there is forage with low proteins:energy
(P:E) ratio (Zicarelli, 1994).
Anyhow, we must underline that buffaloes react to proteic deficiencies better
than dairy cattle (Bertoni et al., 1993).
In Italy the diets used in buffalo breeding contain high proteic
concentrations (between 14.5 and 16.5% CP/DM) and small quantities of
fermentable carbohydrates (between 26 and 30 % of NSC). This does not lead to
deleterious effects on the productive activities of the subjects. On the basis
of our experience, with the above mentioned diets the NH3
levels have resulted lower
than those reported by Jordan et al. (1983) in cattle; in these buffaloes an
increase of the urea levels in blood and milk and probably a greater elimination
of the metabolite through urine occurred. The intake of more proteins increases
the metabolic activity of the hepatic microsomes and this favours the
transformation into urea of the alimentary derivation ammonia
Feeding buffaloes with 6 different energy:proteins ratios Kurar and
Mudgal (1980) have shown that the maintenance requirements of DCP (digestible
crude protein) are equal to 3.2g/kg W0.75
a day and 166.34g DCP/100g of
milk produced proteins. Analogous values were previously observed in Indian
Murrah buffaloes (Sivaiah and Mudgal, 1978/1985).
The results obtained in a study carried out to value the effects of the
energy:proteins ratio on milk characteristics
and on blood and milk urea levels are
the following: 2.53 g of CP/kg W0.75 and
2.7 g of CP x g of protein produced with milk (Campanile et al., 1996a).
According to Rai and Aggarwal (1991) proteic concentrations ranged between 11%
and 14% should be administered to buffaloes during the lactation period. It has
been noticed that the proteic concentration used in Mediterranean buffaloes
could be lower than 12 % (Verna et al., 1992/1994). The proteic
concentration depends on the herd’s milk yield level and on the days in milk.
This changes throughout the year because of the concentration of calvings both
in seasonal herds and in the out of
seasonal ones. Proteic concentrations
9% lower blood and milk urea levels and
increase the milk freezing point, especially if combined to a high level of
fermentable energy (Campanile et al., 1996a). Therefore in order to obtain a balanced diet it is very
important to value the proteins:energy ratio. In buffaloes this ratio may be
higher; in buffaloes the administration of high
proteic concentrations have less deleterious effects than on dairy cows.
Buffaloes use the nitrogen intake with the diet better than cattle even when
there is a lack of carbohydrates (Langer, 1969) because the
buffalo intraruminal environment is more favourable to
the growth of microrganisms
that use NPN (non proteic nitrogen).
In our study we have noticed that the proteic concentration increase (up
to 15% DM) at the beginning of lactation stimulates the productive activity of
the buffaloes without affecting the increase of fat mobilization. NEFA values
were lower higher than those registered in animals that ingested
DM with lower levels of CP. It is known that in cattle a higher proteic
concentration increases milk production because the increase of absorbable
proteins quickens fat mobilization (Orskov et al., 1997; Rulquin, 1992).
Post-ruminal casein infusion determines an increase of the palmitate percentage
(König et al., 1984). It seems that high
proteic concentrations stimulate GH
(Oldham et al., 1978-1982) responsible for the decreased responsivity of the
adipose tissue to insulin, and of a greater sensibility to the adrenergic
stimulus at the end of gestation and
at the beginning of lactation. These stimulus might be mediated by gastroenteric
hormones that can modulate sympathetic nervous system activity (Choung and
Chamberlain, 1992). In confirmation
Cadòrnige and Lopez Diaz (1995) noticed a greater fat mobilization in cattle
that had a higher BCS and fed with diets containing a higher dose of UIP; they
also noticed that their adipose tissue was more sensible to epinephrine
The proteic surplus characterized by unbalances between degradable and
undegradable fractions determines, in dairy cattle, an increase of ammonia in
blood and in the female genital trait. This situation is unfavourable to
the survival of spermatozoa and embryos (Jordan et al., 1983). Moreover
the elevation of ureic nitrogen in
the local (reproductive) or systemic apparatus reduces the ovarian receptors LH
linkage and, therefore, it would be responsible for the lower production of
progesterone in the post ovulation days and of the lowering of the conception
rate. It is known that this ovarian steroid is fundamental for
embryo progression in the uterine tube, for the production of uterine
milk that represents the only nourishment of the embryo before implantation and,
finally, for pregnancy maintenance. Hypoluteinism, characterized by a lower
progesterone secretion in the first phases of gestation, causes early embryo
mortality. It seems that the
unfavourable action of ammonia on reproductive activity is insulin-mediated (Visek,
1984) for its known effects at hypothalamic level. It has been hypothesized that
ammonia acts on the central nervous system through the increase of glutamate and
interrupting the ATP synthesis (Visek, 1984).
A diet with a proteinic content 50% higher than required, has led in
Mediterranean buffaloes to an
increase of heats followed by an appropriate luteinic phase and
a prolongation of the inter-oestrus interval (Campanile et al., 1991a).In this species anaestrous is favoured by lack of CP and energy (Salama
et al., 1982). Analogous results have been noticed in the beef cattle with a
lack of energy and protein (Randel, 1990). Proteinic and/or energetic
underfeeding determines a decrease of ruminal microbial activity and, therefore,
of the whole VFA content. The organism answers through
an increase of GH and a decrease of insulin, allowing the mobilization
of the muscular proteins used for neoglucogenesis and, therefore, for
glycemia homeostasis. Even in this case the reduction of insulin activity could
interfere with buffalo reproductive activity.
It has been demonstrated that land fertilization with 300 kg of nitrogen/Ha/year
in tropical areas increases the conception rate in cows and buffaloes especially
with the addition of 3.5kg of molasses a day (Orr et al., 1994). Land
fertilization with nitrogen increases the forage yield per hectare and increases
the quantity of soluble nitrogen, that is used better by ruminal microflora in
presence of highly fermentable carbohydrates.
Experiments in progress demonstrate that diets containing over 15% CP/DM
and variable doses of degradable proteins administered to buffaloes did not
influence the intercalving interval and ureic and ammonia concentrations
in the vaginal mucus that have resulted lower than those reported by
Jordan et al.(1983) for dairy cattle. Carroll et al. (1988) did not notice
differences as to the urea concentrations in the vaginal mucus of cattle
fed very high
proteinic diet and this whether they had conceived or not. Thus they
hypothesized that the surplus of
nitrogen in the vaginal mucus found in other studies was probably due to other
causes, i.e. contamination phenomena due to faeces, urine and bacterial
infections. The elevation of the ammonia blood levels may reduce the
immunoresponsiveness of the animals (Targowski, 1983/1984).
In the current situation the numerous contradictions present in
international literature do not allow us to exclude the possibility that
proteinic surpluses may have deleterious effects only or most of all in farms
where the sanitary conditions and management are not optimum.
In a study carried out on buffaloes with a higher productive level (>
30 kg of ECM/die) Infascelli et al. (1977) noticed that the increase of the
undegradable protein concentration, obtained
with supplementation of Aspergillus oryzae, determined
a greater milk production, higher blood urea levels and
loss of fertility (Infascelli, personal communication). The authors do
not exclude that this might depend on the different fertility rate of the bulls
used in the different groups. The milk production increase following the better
use of undegradable protein doses
in cows causes a fat
mobilization increase and a negative
energetic balance that would negatively influence
the reproductive phenomena. The
UIP surplus in subjects , whose energy requirements are marginally
satisfied, or in the primiparae fed sufficient energy, determine a
decrease of calving rate (Ferguson and Chalupa, 1989). In this case we can
hypothesize that the
surplus, due to the NEFA utilization, could not be used for the lesser
disponibility of ossalacetiic the following sub -clinical ketosis as is well
known has a negative influence on reproductive performances.
The Ca and P amounts for buffalo maintenance requirement are those
recommended by the INRA French authors (1988)
for dairy cows. As regards production, in consideration of the higher quantity
of these elements contained in milk and of their digestive use, Zicarelli (1990)
recommends 6 - 6.5 g of calcium and 2.2 - 2.5 g of phosphorus for each litre of
milk. Similar requirements are proposed by Proto (1993). In the diet of
lactation groups the Ca:P ratio to use will be 2:1.
It is very important to satisfy the requirements of Ca and P during the
dry period; in buffaloes this
physiological phase lasts at least 120 days and small deficiencies protracted
for such a long time may worsen. It has been reported many times that a diet
with excess of calcium and/or lack of phosphorus or a Ca:P ratio close to the
unit plays an important role in determining vaginal and/or uterine prolapse (Zicarelli
et al., 1982; Campanile et al., 1989). In particular, high Ca:P ratio in the
diet induce an alteration of the normal Ca:Mg ratio at the haematic level
followed by an alteration of the uterine-vaginal fibre muscular excitability,
atony of the organ and prolapse (Campanile et al., 1989). Supplementation with
hyperphosphoric salts (at least during the last phase of gestation)
to obtain the ratios of the
two microelements near to one, stimulates the parathyroid activity (Campanile et
al., 1995) useful to bone re-arrangement immediately after calving.
According to Patak (1989) calcium supplementation in the last gestation
phase reduces the time necessary for placenta expulsion and increases the
haematic levels of this mineral immediately after calving. It is possible to
suppose that - in this case - calcium
administration before calving had positive effects because the subjects received
food containing a high amount of phosphorous or because at the beginning of
lactation they produced such a small quantity of milk that the organism did not
require to use bone calcium.
In buffaloes subjected to A.I. an increase of the heats with an
appropriate luteinic phase and a reduction of double ovulations in the subjects
that received a quantity of phosphorous exceeding requirements of 60% has been
recorded (Campanile et al., 1991a).
Dunn et al. (1992) noticed that
integrating the pasture cow’s diet with phosphorous before and after calving
reduces the calving oestrus interval
and the effects strengthen if combined with a higher protein administration.
Selenium supplementation becomes particularly important, especially if
carried out during the dry period, because
it reduces, in buffaloes as well as in cows, placenta retentions and favours a
ready recovery of the reproductive activity immediately after calving,
because of uterine phlogosis reduction (Smith et al., 1995). In cows this
microelement added to vit. E activates the immunity system (Harrison et al.,
1984). In buffaloes, diet integration with 4200 mg of vit. E + 4.2 mg of Se or
with a AD3 vitamin complex during the dry period and after calving reduces the
calving-1st heat interval (Ezzo, 1995). In confirmation of this datum Hurley and
Doane (1989) report that the alimentary supplementation with
or vit. A increases the pregnancy rate, reduces the calving conception-interval
and the number of services required for conception in cow. The presence
and of vit. A in cow luteinic cells (Chew et al., 1984) and follicular liquid (Schweigert
and Zucker, 1988), leads us to
suppose that these two vitamins play a very important role in the functionality
of these organs. On this regard - in a trial carried out on cow -
Schweigert and Zucker (1988) found a
high correlation between estradiol-17
and vit. A in fluid from healthy follicle compared with atresic or small
In buffaloes as in sheeps - "white milk species"-
turns into vit. A immediately after
assimilation (Zicarelli et al., 1986). It follows that the corpus luteum does
not appear yellow as usual. Many experiences demonstrate that the administration
of about 400.000 U.I. of vit. A and
10.000 of vit. D3 some
months before bull entry and during the dry period improves the herd conception
rate. During winter time buffalo diet
vitamin integration becomes necessary where low temperatures and, probably, the
lower activation of vit. D at cutaneous level cause hair fall and a lower
resistance to ectoparasitic infestations.
In buffalo heifers the beginning of the ovarian cyclic activity depends
on live weight; in fact it has been observed that buffaloes have normal oestrus
cycles when they reach 2/3 of their adult body weight (Campanile et al., 1991b; Esposito et al., 1992). Nutrition plays an important role on the
beginning of the reproductive activity. In the Mediterranean buffalo (Campanile
et al., 1991b; Esposito et al., 1992)
there is a puberal retard when in the months preceding puberty insufficient
energetic levels are adopted. In the
trials carried out till now we have
noticed that subjects having a daily body weight gain (BWG)
> 500g reach puberty about 50 days before those with
lower BWG; this occurs if high energetic levels are not followed by low
ones. Positive effects occur, instead, when low nutritive levels are followed by
high ones. Afidi et al. (1979) noticed that reproductive activity did not
benefit by a 20% and 35% increase of
diets that guaranteed a BWG mean
increase of about 450 g in about 15-month-old subjects. According to El Nouty
(1971) an earlier of puberty and conception
age occurs in subjects fed
rationally since weaning. In a study
carried out on 25 Murrah heifers,
Prased et al. (1995) noticed that
protein and phosphorous excesses (30% and 150% more than requirements,
respectively) delay first heat and conception age, and increase the number of
services required per conception. Results in progress demonstrate that
Mediterranean heifers that received 1 kg of CP a day had a lower conception rate
compared to those that received 800 kg of CP a day. Even in this case conception
occurred when the animal’s live weight was included between 370 and 380 kg (
about 2/3 of adult body weight). In many trials (Kamonpatana et al., 1988; Mc
Cool et al., 1988; Borghese et al., 1997) it has been reported that in buffaloes,
aside from race, the beginning of puberty occurs at different ages but generally
it occurs when they weigh more than 300 kg, i.e. 2/3 of the adult live weight.
It may be hypothesized that a modification of the GH and insulin ratio at
haematic level occurs. This condition favours LH pulsate secretion and,
therefore, the beginning of puberty.
nutrition effects on reproductive performances are more evident in those
countries where buffalo cow during the most favourable periods for their ovarian
cyclic activity and where, thanks to the climate, forage availability
changes throughout the year.
Italy the rationalization of buffalo
breeding and the necessity to modify calving calendars in order to satisfy
market demand, leads to the reproduction of this animal in a period known to be
unfavourable to its reproductive activity. The atmospheric conditions (number of
day light hours, rainfall, cold winds, thermal excursion, etc.) in this case
worsen the reproductive performances. Nutritive errors, i.e. unbalances between
the various nutritive principles during the phase preceding sexual promiscuity,
may have negative effects on the reproductive performances. This situation
occurs more frequently when there is irrational pasture and when green forage is
administered. Forage essences have a variable chemical composition that modifies
the nutritional intake, especially during
the positive photoperiod months (spring) that in Italy correspond to the months
in which sexual promiscuity starts again. The continuous modification of
nutritional levels is responsible, in many cases, of the cyclic activity break
in young subjects and in those in lactation.
and food quality, an aspect which breeders often disregard, have great
importance. Badly preserved or overripe forage oblige
technicians to increase concentrate portions; the effects on fertility
are deleterious. Moreover, there are the effects of the toxic substances
produced by fungi that colonize food especially poor silages quality.
the results reported herein, and the many conflicting opinions it appears clear
that meeting of nutritional requirements is only one of the factors that can
influence the reproductive phenomena of a species like the buffalo that does not
yet a lactiferous habit. Stimulating production by means of a rich diet gives
results that depend on the sanitary conditions in which the buffalo lives and on
the breeder’s managerial abilities. An effective collaboration between
breeders and technicians is the only way to maximize the productive activity of
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