Our Blog

List of recently published project topics and materials

PROJECT TOPIC- EFFECT OF AMBIENT TEMPERATURE ON THE PHYSIOLOGICAL RESPONSE, GROWTH PERFORMANCE, HAEMATOLOGY AND SERUM BIOCHEMICAL INDICES OF NEW ZEALAND WHITE RABBIT

PROJECT TOPIC- EFFECT OF AMBIENT TEMPERATURE ON THE PHYSIOLOGICAL RESPONSE, GROWTH PERFORMANCE, HAEMATOLOGY AND SERUM BIOCHEMICAL INDICES OF NEW ZEALAND WHITE RABBIT

ABSTRACT

This study was conducted to investigate the effect of ambient temperature on the physiological responses, growth performance, haematology and serum biochemical indices of New Zealand White Rabbits. The experiment lasted for 56days. The rabbits were allotted in a completely randomized design (CRD) to three treatment groups identified as T1, T2 and T3 consisting of six replicates. The T1 group was reared under normal thermo-neutral zone (the control) ranging from 33 to 35oc; the T2 was treated by placing 200watts of bulb in the cage with air temperature (37 to 39oc) and the T3 group was reared in cold chamber in the presence of electrical fan and/or placing gallon filled with cold water in the cage with air temperature (28 to 30oc). Results revealed that there were significant (p<0.05) differences among all the growth performance parameters of NZW rabbits under different ambient temperature zone except for the final body weight. There was significant differences (p<0.05) on weight gain, daily weight gain , daily feed intake and feed conversion ratio such that they were lower, for growing rabbits subjected to elevated temperature, while there was significant difference on daily water intake on T2. The rectal temperature and pulse rate were significantly different (p<0.05) such that, the rectal temperature and pulse rate were higher in rabbits in the T2. The rabbits on the T2 had a significant decrease (p<0.05) in their packed cell volume, red blood cell and white blood cell. On the other hand, significant increase (p<0.05) were found in the numerical value of haemoglobin concentration, platelets, mean corpuscular haemoglobin, mean corpuscular volume and mean corpuscular haemoglobin concentration. This result shows that the performance of rabbits on intense heat chamber can be improved by applying some techniques for the alleviation of the heat stress by using electric fan and/or placing a gallon filled with cold water in the cage to lie beside them or on it.

CHAPTER ONE

INTRODUCTION

Rabbits are hoped to play an important role in solving meat production deficiency particularly in the developing countries such as Nigeria. These developing countries are mostly localized in tropical and subtropical region. So, rabbits have suffered from many problems related to hot climate particularly heat stress. Rabbits tend to have a constant internal body temperature; so, heat production must be coped with the losses to maintain the body temperature constant.

They do this by modifying their physiological and behavioral status. The rabbit is highly susceptible to high ambient temperature because it cannot effectively sweat and panting is not efficient for cooling (Brewer and Cruiser 1994, Maria et al., 2002) Most of the sweat glands in rabbits are not functional and perspiration (evacuation of water via the skin) is never great because of fur, the only controlled means of latent heat evacuation is by altering the respiratory rate (Abel el-same 1987).

A study in rabbit revealed that puberty was not delayed but age at first mating was also increased and the body weight decreased in heat stress. The comfort zone for rabbit is 15oc – 20oc; so rabbits can withstand cold weather than warmer one. The metabolic rate increased by about 20% in rabbits when exposed to high air temperature ranging from 30-35oc (Gonzalez et al., 1981), while, the feed intake was decreased (Rake et al., 1988 and Habeeb et al., 1993).

According to broody (1995) the thermal neutrality zone of this specie is 21 – 23oc but it may be different when insulation, posture or basa metabolic rate vary (IUPS, 2001). All these factors are subject to change as the animal grows; therefore heat production and dissipation will change as age advances. The breeding of rabbits is expanding; this is mainly attributed to the rabbit’s high rate of reproduction, high genetic selection potential, rapid growth rate, early maturity, efficient feed utilization, high quality nutrition meat and limited competition with human for similar foods (Habee et a.,l 1992; Ayyt and Marai et al., 1999).

However the most obvious limitation to rabbit production in regions with hot climate is the susceptibility of this species to heat stress. Heat stress is defined as a stress inflicted by a wide range of environmental conditions that induce a state of physiological strain within an animal’s body and means that animals are not able to regulate their heat homeostasis passively. It mainly occurs when animals are exposed to high ambient temperatures, high humidity, low wind speed and high direct and indirect solar radiation (Willmer et al., 2000).

The ears are important heat regulating organs in the rabbits because they represent about 12% of the body surface area and are highly vascular. Therefore, they have a relevant role for sensible heat – loss. (Luke fahr and Ruiz-feria, 2003). Further disturbance in feed intake, feed utilization, water metabolism, blood parameters, enzymatic reactions, hormonal secretions, in addition to protein, energy and mineral imbalances had been also reported to be disrupted in heat-stressed rabbits (Habeet et al., 1996). Okab and AL-Banna, 2005; Burnett et al, 2006; Okab et al., 2008).

Comparing breeds or strain under the same environment may reveal specific preference levels due to difference in the genotypical values of animals (Lebas et al., 1996). Conversely, a specific environmental difference could have a greater effect on some genotypes than others or there could be a change in the order of merit of a series of genotypes when measured under different environments, characterizing a genotype x environment interaction (Fal coner and Kay, 1996).

The continuous rise in temperature is clearly affecting the mediterean area, with an extension of the summer season (Come et al., 2009). As well as genetic and management, temperature also plays an important role in the animals welfare and health. The relationship between high temperature and mortality is well known in people living in urban areas, but it has been poorly investigated in livestock (Crescio et al., 2010). These challenges have a major and obvious impact on animals and their physiological activities; in fact, it has been described that high environmental temperature produce an adverse effect mainly on reproductive process (Sirotkin, 2010) and mainly on reproductive traits (Amaral et al., 2011).

PROJECT TOPIC- EFFECT OF AMBIENT TEMPERATURE ON THE PHYSIOLOGICAL RESPONSE, GROWTH PERFORMANCE, HAEMATOLOGY AND SERUM BIOCHEMICAL INDICES OF NEW ZEALAND WHITE RABBIT

  • Aims of the Study;

This study is aimed at investigating the effect of ambient temperature on physiological indicators of heat stress and performance of growing rabbits.

  1. Determine the influence of ambient temperature on the growth performance of New Zealand white rabbits.
  2. Evaluate the physiological indicators of ambient temperature to New Zealand white rabbits.
  3. The serum biochemical indices of New Zealand white rabbits on difference environmental zone.
    • Justification of the Study;

The identification of genetic group or genotypes that have superior performance in warm environments is of extreme importance for the development of rabbit meat production in the tropics.

The European Food and Safety Authority (2005) pointed out the importance of ambient temperature for rabbit health and emphasized the need for further studies to investigate the adequate environmental conditions for weaned rabbits. The NRC (1996) recommended that ambient temperature be maintained between 16 to 22oc for rabbit under laboratory confinement. According to Broody (1964) the thermal neutrality zone for these species is 21oc to 25oc, but it may be different when insulation, posture or basal metabolic rate varies (IUPS, 2001).

PROJECT TOPIC- EFFECT OF AMBIENT TEMPERATURE ON THE PHYSIOLOGICAL RESPONSE, GROWTH PERFORMANCE, HAEMATOLOGY AND SERUM BIOCHEMICAL INDICES OF NEW ZEALAND WHITE RABBIT

Was the material helpful? Comment below. Need the material? Call 08060755653.