ABSTRACT

Two studies were carried out to determine the nutritive value of Ma lted Sorghum Sprouts (MSS) in broiler chickens. The first trial was conducted to determine the effect of graded levels of MSS in a isocaloric- isonitrogenous diets on performance, carcass, and hematological parameters. A total of two hundred and seventy birds were used for both the starter and finisher phases. There were five dietary treatments, replicated three times with eighteen birds per pen and a total of fifty four birds per treatment in a completely randomized design. Five isocaloric-isonitrogenous experimental diets were formulated to contain MSS at 0, 5, 10, 15 and 20% to compliment other energy components in the diets. The experiment lasted for eight weeks. In the second set of experiments, two hundred and seventy birds were allotted to five dietary treatments with three replicates per treatment containing eighteen birds per pen. Birds were fed five’ isocaloric-isonitrogenous diets with Maxigrain® enzyme treatment i.e. MSS at 0% (Trt l), 10% (Trt 2), 10% + Enzyme (Trt 3), 15% (Trt 4) and 15% + Enzyme (Trt 5). Data analysis revealed that dietary treatments had significant (p<0.05) effect on feed intake, body weight gain, feed conversion ratio, feed cost/kg gain, carcass and blood parameters taken. Feed intake was significantly (p<0.05) the lowest for birds fed diet 5 while those on diet 2 had the highest values. Body weight gain significantly (p<0.05) decreased as the percent MSS increased in diets. Feed conversion and cost/kg gain significantly (p<0.05) favored birds on diet 2 compared to those on diet 1, 3, 4 and 5 respectively. Blood parameters were significantly (p<0.05) affected by experimental diets but differences were within expected limits. Feed intake was significantly the highest in Trt l and least in Trt 5. Trtl was numerically the highest in final weight and weight gain but did not differ (p>0.05) from trt3. Trts 2 and 5 recorded the lowest final weight as daily weight gains were least for these treatments. Trt 3 had the best feed conversion ratio and cost/kg gain with Trts 4 being the lowest. Dietary treatments had effect on breast, thighs, and other cuts and organs while drumstick, wings, back and lungs showed no difference. Hb and TP significantly differed but not PCV though values were within recommended range. These studies showed that birds in treatment 1 gave the best results in both experiments but, MSS can be included at 5% or at 10% with enzyme treatment for good performance, reduced feed cost and better feed conversion ratio. Mortality was not significantly (P>0.05) affected by MSS inclusion. It is therefore recommended that MSS in broiler diets should not exceed 10% levels of inclusion as the overall performance of birds become poorer with increased levels in the dietDownload Full Material-N5000

Abstract

 

A study was conducted to evaluate the effects of thermal indices and relationship with milk yield in dairy cows using invasive (glucose, total cholesterol, triiodothyronine (T₃), thyroxine (T4), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and inorganic phosphate) and non-invasive (Rectal temperature (RT), respiration rate (RR), ear temperature (ET) and skin temperature (ST) markers in the Sahel Savannah of Nigeria. Fifteen (15) clinically healthy dairy cows of three breeds; five each from Holstein Friesian purebred, Simmental and Brown Swiss, aged 5-8 years from Sebore Farms were used for the experiment. The animals were maintained on similar feeding programme under hot-dry and cold-dry season. Data collected includes thermoregulatory variables: Rectal temperature, respiration rate, ear temperature and skin temperature), blood biochemical variables (glucose, inorganic phosphate, total cholesterol, triiodothyronine (T₃), thyroxine (T₄), aspartate aminotransferase (AST), and alanine aminotransferase (ALT), daily milk yield and milk component traits (protein and fat percentage). All the thermoregulatory parameter values differed significantly (P<0.05) between the seasons with the exception of ear temperaturewhich was statistically similar (P>0.05). Rectal temperature, respiratory rate and skin temperature were significantly (P<0.05) higher during hot- dry season compare to cold-dry season.Glucose, ALT and AST differed significantly (P<0.05) across the breeds of dairy cows while cholesterol, phosphorus, T₃ and T₄ were statistically similar (P>0.05). The serum ALT was higher in Simmental (47.74±1.33iu/l) and Brown Swiss (46.59±1.33iu/l) which differed significantly (P<0.05) from Holstein Friesian cows (39.1±1.33iu/l).However, all the biochemical parameters differed significantly (P<0.05) between the cold-dry and hot-dry seasons with the exception of T₃ which was statistically similar (P>0.05).Milk yield was significantly (P<0.05) higher during the cold-dry season (8.03±0.24kg)

 

than the hot-dry season (6.93±0.21kg) while fat (P<0.05) was significantly higher during the hot than the cold season. Holstein Friesian had the highest average daily milk value (8.16kg) while Simmental cow had the lowest milk volume (7.08kg). Simmental and Brown Swiss cows had the highest percentage of fat (4.07%) which were statistically different (P<0.05) from Holstein Friesian (3.88%). Protein showed no (P>0.05) significant difference between breeds. Daily milk yield was significant, low and negatively correlated with temperature (R=-19, P=0.0005) while moderate, significant and negative correlations was observed with THIand RH (R=-0.24, P=0.0005 and R=0.26, P=0.0061) Fat had significant, low and positive relationship with temperature (R=0.17, P=0.0019) while low and positive relationship existed with THIand RH(R=0.19, P=0.76 and R=0.12, P=0.059). Protein had low and negative correlations with all the environmental factors with the exception of temperature which was positively associated (R=0.003, P=0.9501).Daily milk yield was significant and highly correlated with phosphorus (R=0.52; p=0.02) and T₄ (R=0.94; p=0.05) but significant, high and negatively correlated with T₃ (R=-0.51).Cholesterol was significant, high and negatively correlated with DMY  (R=-0.28). AST was significant, moderately and negatively correlated with DMY (R=-0.26). ALT was negatively correlated with DMY. The regression analysis for prediction of milk yield showed that all the invasive markers combined together best explained daily milk yield (R²= 0.52) in Brown Swiss dairy cows compare to Simmental and Holstein Friesian which were weakly predicted (R²= 0.18). The regression analysis for prediction equation using non-invasive markers, showed that all the non-invasive markers combined together explains only (R²= 0.05)  of milk yield when the breeds were pooled. It was concluded that invasive parameters could be a veritable tool in predicting daily milk yield of different genotypes of dairy cows under the Sahel Savannah                condition of                                                    Nigeria.

 

 

CHAPTER ONE

 

                                                                                                        INTRODUCTION

 

Heat stress plays a significant role in cattle performance and likely will be of even greater importance in the future as climate change continues. Cattle are produced in a wide range of environments, some of which present thermal challenges to productive performance, even survival in extreme cases. High temperatures can have negative consequences for milk production, and for reproduction, welfare and health, in dairy cattle. Especially high yielding dairy cattle would be susceptible because their thermo-neutral zone is rather limited as compared to low yielding cows (Kadzere et al., 2002). As a result of heat stress, losses of 600 to 900 kg milk per cow per lactation has been reported with regard to milk production (West, 2003).Selection of cattle adapted to warm environments represents one strategy to mitigate the effects of heat stress. There are a number of environmental factors that contribute to heat stress; these include high temperature, high humidity and solar radiation. In tropical regions, animals must be able to balance heat production and heat gain from their environments with dissipation of heat through the skin and respiratory surfaces; simultaneously, they must avoid excessive thermal energy incoming from the environment (Da-Silva et al.,2003).

The productivity and health of these animals are being affected by adverse meteorological conditions prevailing in the tropical Africa, predisposing them to hyperthermia (heat stress) and hypothermia (cold stress) (Da-Silva et al.,2003). In the tropical conditions of Nigeria, heat stress is common during dry season, occurring between November and May and with a mean monthly rainfall of less than 51mm (Igono et al., 1982; Walter, 1969). The harmattan season is characterized by marked fluctuations in ambient temperature (AT) with high AT in the afternoon

 

hours of the day and relatively low temperature of about 10 ^OC in the evening and early morning hours of the day. The season is associated with a dry cold and dust-laden wind that blows from Sahara desert and low relative humidity (RH) (Ayo et al., 1998a). The hot-dry season is also characterized by high ambient temperature, relative humidity and long duration of sunshine. Of all the stress factors adversely affecting dairy production in the tropical environment, ambient temperature manifesting in hypothermia and hyperthermia and humidity changes are the most crucial. It has been shown that high ambient temperature and high relative humidity with wide fluctuations in the values result in heat stress which may alter many physiological parameters in livestock (Ayo et al., 1998b; Sinkalu et al., 2009). These may impair homeostatic mechanisms resulting in pathological changes and alteration in body homeostasis (Teeter et al., 2005).

The general homeostatic responses to thermal stress in mammals include a decrease in fecal and urinary water losses, a reduction in feed intake and production, and an increase in sweating, respiratory and heart rates. Most of the adjustments made by the cow involve dissipating heat to the environment and reducing the production of metabolic heat (Kadzereet al., 2002). As milk production increases in dairy cattle, the metabolic heat production rises with the metabolizing of large amounts of nutrients, which makes the high producing cow more vulnerable to high environmental temperatures and humidity than animals that are metabolically less active (Kadzere et al., 2002). High producing dairy cows must dissipate large amounts of heat produced during the metabolism of high dietary energy used for body maintenance and milk synthesis. Several studies reported that heat stress in dairy cattle affects production and reproduction (Garcia-Ispierto et al., 2007; Morton et al., 2007; Bryant et al., 2007). Despite the moderate effects of THI on milk production, some blood parameters related to energy balance and enzyme activities had significant alterations and cows in the middle of lactation had the highest changes

 

in these parameters (Dikmen et al., 2008). These authors have indicated that the thermoregulatory characteristic of animals associated with this phenotype is probably due to a lower metabolic rate, increased sensible heat or evaporative heat loss, more efficient transfer of heat to the surface, or a combination of these adaptations. They further reported that dry bulb temperature is nearly as good a predictor of rectal temperatures of lactating Holsteins in a subtropical environment as THI. Hormones known to be homeorhetic regulators are also implicated in acclimatory responses to thermal stress. These include thyroid hormones, prolactin, somatotropin, glucocorticoids and mineralcorticoids. Triiodothyronine (T₃) and thyroxine (T₄) are hormones associated with metabolic homeostasis and susceptible to climatic changes (Perera et al., 1986). Johnson et al. (1988) also showed decline in thyroid hormones T₃ and T₄ in response to heat stress which is an attempt to reduce metabolic heat production in the cow. Stress response hormones (glucocorticoids) are elevated during initial heat stress exposure and then become depressed with prolonged periods of thermal stress. Wheelock et al. (2006) demonstrated that heat stress elevates plasma insulin concentrations in lactating dairy cows and this may be important for glucose disposal in peripheral tissues. The blood biochemical profiles are considered important in evaluating the health status of animals. The estimates of biochemical constituents are the prerequisites to diagnose several pathophysiological and metabolic disorders in cattle (McDowell et al., 1992). Numerous authors reported close relationship between blood levels of calcium, phosphate, total protein, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and reproductive traits in dairy cows (Malik et al.,2003).

              Justification

 

There is paucity of information on the use of thermoregulatory and biochemical parameters as markers of heat stress in dairy cows reared in Northern Nigeria especially the Sahel savannah regions. Information on effect of varying environmental/climatic conditions on thermoregulatory and biochemical parameters is particularly important in Northern Nigeria as dairy milk production is generally low in this area compared to the temperate regions of the World. A study to investigate whether or not thermoregulatory and biochemical parameters could be used to estimate adaptability of exotic dairy cows to varying environmental conditions is then necessary. The vital and biochemical parameters are of significant diagnostic values for the spot assessment of health status of dairy cows. These parameters have been demonstrated to be important indices of health, production and adaptability to prevailing environmental conditions in livestock (Oladele et al., 2001; Oladele et al., 2005; Adenkola and Ayo, 2009).

              Objectives

 

The objectives of this research were to:

 

• Evaluate the variation in thermoregulatory(non-invasive)parameters in acclamatory responses to thermal stress in exotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria
• Evaluate the variation in bloodbiochemical (Invasive) parameters in acclamatory responses to thermal stress in exotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria

 

• To establish the relationship between milk production characteristics and blood biochemical profiles inexotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria
• To establish prediction equations for total milk yield using invasive and non invasive parameters

              Research Hypotheses

 

H₀There is no variation in thermoregulatory(non-invasive)parameters in acclamatory responses to thermal stress inexotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria

H_aVariation existed in thermoregulatory(non-invasive) parameters in acclamatory responses to thermal stress inexotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria

H₀There is no variation in bloodbiochemical (invasive)parameters in acclamatory responses to thermal stress inexotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria

H_a Variation existed in bloodbiochemical (invasive) parameters in acclamatory responses to thermal stress inexotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria

H_o There is no relationship between milk production characteristics and blood biochemical profiles inexotic breeds of dairy cows under Sahel (semi- arid) region of Nigeria

H_a There is relationship between milk production characteristics and blood biochemical profiles inexotic breed of dairy cows under Sahel (semi- arid) region of Nigeria

 

H_o The prediction equation for total milk yield using invasive and non-invasive parameters is weak using coefficient of determination as judgement criteria

H_a The prediction equation for total milk yield using invasive and non-invasive parameters is strong using coefficient of determination as judgement criteria.Download Full Material-N5000

ABSTRACT
Two trials were conducted for a period of 90 days each to evaluate the feeding value of
different proportions of urea treated rice straw and gamba hay in the performance of
growing and fattening Yankasa rams. In the first trial, twenty four (24) growing Yankasa
rams of mean initial body weight of 15.77±2.5 kg and aged 6 – 8 months were allotted to
four dietary treatments with six (6) animals per treatment in a Completely Randomized
Design. Urea treated rice straw and gamba hay proportions of 0:60, 20:40, 40:20 and 60:0
were used as roughage diets. A concentrate diet consisting of maize grain, cotton seed
cake, rice milling waste, wheat bran, bone meal and salt was formulated to contain 15 %
crude protein. The animals were fed roughage diets ad libitum while concentrate was fed
at 1.5% of individual body weight. Data were collected on growth performance and blood
profile. Data generated were subjected to analysis of variance and differences in means
were compared using Duncan’s Multiple Range Test. The result of chemical analysis
showed that treatment of rice straw with urea increased its crude protein content from
3.64 to 8.89 % and decreased the neutral detergent fibre content from 72.16 to 67.98 %.
Total dry matter intake varied from 263.11 to 325.01 g/day with the highest value
recorded in animals fed 60:0 UTRS:gamba hay diet. Results of crude protein and neutral
detergent fibre intake followed similar pattern. The highest (P<0.05) average daily gain
(79.81 g/day) was obtained in growing rams fed 60:0 UTRS:gamba hay diet while the
lowest (P<0.05) value (44.44 g/day) was obtained in animals fed 0:60 UTRS:gamba hay
diet. Growing rams placed on 60:0 UTRS:gamba hay diet had the lowest (P<0.05) feed
conversion ratio value (7.77). Dry matter digestibility was significantly (P<0.05) affected
by UTRS:gamba hay proportions. Animals fed 60:0 UTRS:gamba hay diet had a high dryxviii
matter digestibility (67.62%). The digestibility of other nutrients followed the same
pattern. Animals fed 60:0 UTRS:gamba hay diet had significantly (P<0.05) higher
nitrogen intake (16.12 g/day) and the lowest (P<0.05) in the diet containing 0:60
UTRS:gamba hay (12.06 g/day). Nitrogen balance significantly (P<0.05) differed across
the dietary treatments. Animals fed diet containing 60:0 UTRS:gamba hay had high
nitrogen retention (13.30 g/day) while those fed 0:60 UTRS:gamba hay diet had low
nitrogen retention (7.78 g/day). With exception of serum creatinine, all the serum
parameters measured were significantly (P<0.05) different. Animals on 60:0
UTRS:gamba hay diet had higher (P<0.05) value of serum glucose (61.02 mg/dl) while
animals fed 0:60 UTRS:gamba hay diet had the lowest (P<0.05) value (49.55 mg/dl).
Serum urea nitrogen and total protein followed similar pattern. In the second trial, twenty
(20) intact Yankasa rams with mean initial body weight of 21.87±2 kg and aged 12 – 18
months were allotted to four dietary treatments with five (5) animals per treatment in a
Completely Randomized Design. Urea treated rice straw and gamba hay proportions of
0:60, 20:40, 40:20 and 60:0 were used as roughage diets. A concentrate diet consisting of
ingredients similar to those of the first trial was formulated to contain 13 % crude protein.
The animals were fed roughage diet ad libitum while concentrate was fed at 2.0 % of
their individual body weight. Data were collected on growth parameters, serum blood
profile and rumen liquor metabolites. Data generated were subjected to analysis of
variance and differences in means were compared using Duncan’s Multiple Range Test.
The result of chemical analysis of the experimental diets was similar to that obtained in
the growth trial. The result revealed that, there were significant (P<0.05) differences on
all the growth parameters measured. Total dry matter intake was significantly (P<0.05)xix
higher (1035.98 g/day) in animals fed diet containing 60:0 UTRS:gamba hay compared
to those fed the rest of the diets. Similarly, animals fed 60:0 UTRS:gamba hay diet had
high average daily gain (72.89 g/day) compared to animals on other diets. Lowest
(P<0.05) value (38.00 g/day) was recorded in animals fed 0:60 UTRS:gamba hay diet.
Rams fed 60:0 UTRS:gamba hay diet had the least (P<0.05) feed conversion ratio (14.21)
indicating that animals on diet containing 60:0 UTRS:gamba hay were more efficient in
converting feed to live weight gain than animals fed other diets. Digestibility of nutrients
was significantly (P<0.05) different across the treatment groups. Total nitrogen intake
and nitrogen retention were significantly higher (P<0.05) in animals fed diets containing
60:0 and 40:20 UTRS:gamba hay. No significant (P>0.05) difference was observed on
rumen fluid pH while significant (P<0.05) differences were obtained on rumen ammonia
nitrogen and Total volatile fatty acids (TVFA). Animals fed 60:0 UTRS:gamba hay diet
had higher (P<0.05) rumen ammonia nitrogen and TVFA (27.80 mg/dl and 16.13
Mmol/l, respectively). Lowest (P<0.05) values (21.79 mg/dl and 12.98 Mmol/l,
respectively) were obtained in rams fed 0:60 UTRS:gamba hay diet. Significant (P<0.05)
differences were observed on all blood profile parameters measured except the serum
creatinine. The serum glucose, urea nitrogen and total protein values ranged from 50.29
to 61.32 mg/dl, 5.73 to 8.64 mg/dl and 58.77 to 67.03 g/l, respectively. Values obtained
for serum glucose, urea nitrogen, serum creatinine and total protein fell within the normal
ranges of 50-100 mg/dl, 15-30 mg/dl, 1-2.7 mg/dl and 60-79 g/l, respectively for sheep.
In terms of economic benefit, the results revealed that cost of feed consumed per kg body
weight gain (497.76 ₦/kg) was lower and better in fattening rams fed diet containing 60:0
urea treated rice straw:gamba hay proportions. The study recommends that urea treatedxx
rice straw and gamba hay proportions of 60:0 UTRS:gamba hay could be used to replace
gamba hay as sole roughage diet for sheep feeding as sheep had higher weight gain in the
treated straw based diets compared to gamba hay based diet. The study further
recommends that small-holder farmers may adopt the treatment of rice straw with urea to
improve its nutritive value and reduce the cost of feed per kg body weight gain.1.0
1
CHAPTER ONE
INTRODUCTION
Sheep are important part of the global agricultural economy and they play a major role in
many local economies (Weaver, 2005). Njidda and Kibon (2004) stated that sheep are
multipurpose animals, but they are primarily kept for the production of meat (mutton),
and they account for about 11% of the total meat supply in Nigeria. The authors further
stated that the inclusion of animals slaughtered in the rural areas outside the slaughter
houses would have made this figure higher. Afolayan (1996) reported that Yankasa sheep
is very popular among sheep farmers, most especially in northern Nigeria. Their high
productivity in terms of growth performance and prolificacy are paramount to the farmer
(Akpa et al., 2006). Inadequate and poor quality of feed, especially during the long dry
season is one of the major factors militating against livestock production in Nigeria. The
seasonality of feed supply in northern Nigeria has affected animal production adversely
(FDLPCS, 1992).
According to Rumirez-Orduna et al. (2005), due to high cost, most smallholder livestock
farmers cannot afford to supplement the diet of their animals with expensive feed
ingredients. Production of livestock and their productivity are far below the population’s
requirement for animal protein. This under-production and low productivity are attributed
mainly to inadequate year-round availability of feed and water, coupled with poor
management (Abbey et al., 2001). In the Savannah zone of Nigeria the basal diets of
most ruminants in the dry season is based on crop residues and dry standing grasses, and
most of these feed resources are imbalanced in nutritional value and vary from year to
year (Zemmelink, 1999).2
The natural rangeland serves as the major sources of forages for ruminants in Nigeria.
Rangeland forages, however, decline in both quality and quantity during the dry season,
resulting in low productivity of animals. Gamba (Andropogon gayanus) is a tropical grass
which is widely distributed throughout the savanna ecology of Nigeria and forms the bulk
of feed available to ruminants grazing on rangelands (Fitzhugh, 1978). Gamba grass is
usually established as permanent pasture in most commercial ranches or smallholder
farms. It can be cut as fresh feed or conserved as hay. The crude protein content of gamba
grass is moderate in young growth (7 – 10%) but declines rapidly with maturity (2 – 5%)
(Leeuw, 1979; Agishi, 1985). Alli-Balogun (2010) reported CP, NDF and ADF contents
of gamba hay as 3.76, 76.4 and 56.2%, respectively.
Rice straw, like other cereal crop residues is a potential source of energy for ruminants.
However, its potential as an energy source is limited because it is high in dietary fibre
(>50%) and low in crude protein (2 – 7%) and mineral contents (0.02 – 0.16%) (Sundstol
and Owen, 1984; Jung et al., 1993). One way in which, the low nutritive value of rice
straws could be improved, is through treatment with urea. In feeding trial strategies for
improving milk production by Ehoche (2002), urea treatment of crop residues is
acknowledged to improve nutritional value of crop residues and other fibrous by-products
and reduce feed cost and wastages with practical application at the smallholder level in
developing countries. The author further stated that in the tropics, cereal crop residues
such as maize, sorghum, millet stover and rice straw were produced in large quantities
and could be used as ruminant livestock feeds. Akande (2001) reported that in Nigeria,
rice is cultivated in virtually all agro-ecological zones and the residue (straw) can beJustification
Utilization of crop residues as feed has been the subject of intense research and
development worldwide since the mid1970s but there appears little effort has resulted in
greater utilization of crop residues in developing countries (Owen and Jayasuriya, 1989.
Kalio et al. (2013) reported that in Nigeria, millions of tons of crop by-products are
generated every year in our rural communities as unavoidable crop by products or
residues. Akande (2001) reported that in Nigeria, rice is cultivated in virtually all agro-
ecological zones. There is a tendency that paddy rice will be more available in future
through the recent Presidential initiative on rice production in Nigeria which is aimed at
encouraging local rice production in order to reduce over-dependence of the country on
imported rice (James, 2011) which means increase in rice straw output in the country.
Due to lack of adequate disposal facilities, most of the rice straw generated from rice
farming in Nigeria are left in the fields to be partially grazed by large ruminants only
without small ruminants benefitting as rice straw is inefficiently utilized by them because
3
obtained or purchased at relatively cheap or free of charge from all rice farms. According
to FAO (2012), Nigeria is the second largest producer of rice in Africa after Egypt and
the largest in West Africa. FAO (2013) reported that Nigeria production of paddy rice
was estimated at 4,700,000 tonnes. This gives rise to increase in rice straw output in the
country which could be harnessed for ruminant livestock feeding. It was also reported by
Parnich (1983) that, information on the utilization of rice straw in the diets of sheep is
scanty. The use of rice straws could help improve ruminant livestock production, if its
nutritive value is enhanced.Download Full Material-N5000