EFFECT OF EJACULATION FREQUENCY AND MANAGEMENT CONDITIONS ON SEMEN QUALITY, FERTILITY AND HATCHABILITY OF LOCAL TURKEYS IN THE HUMID TROPICS

TABLE OF CONTENTS

Title page————————————————————————-     i

Certification————————————————————— ii

Acknowledgement————————————————————–      iii

Table of contents—————————————————————-     iv

CHAPTER ONE: INTRODUCTION

1.1Background of the Study—————————————————— 1

1.2 Statement of the Problem—————————————————– 5

1.3 Objective of the Study——————————————————— 5

1.4 Justification of the Study—————————————————– 6

CHAPTER TWO: LTERATURE REVIEW

2.1 Anatomy of the reproductive system of the Tom————————— 8

2.2 Spermatogenesis in Toms———————————————— —- 9

2.3 Factors that affect Semen Production———————————– —- 12

2.3.1 Ambient Temperature——————————————————- 13

2.3.2 Photoperiod or daylight length—————————————- —- 13

2.3.3 Nutrition———————————————————————- 15

2.3.4 Age—————————————————————————- 15

2.3.5 Breed/Species Variation—————————————————- 16

2.4 Semen Collection Techniques———————————————— 16

2.4.1  Handling male turkeys for collection of Quality Semen—————- 16

2.5 Frequency of Semen Collection in Turkeys——————————— 18

2.5.1 Factors Affecting post-ejaculation Semen Quality———–           —- 20

2.5.2 Ambient temperature————————————————— —- 20

2.5.3 Semen Osmotic Pressure———————————————– —- 21

2.5.4 Semen PH——————————————————————— 21

2.5.5 Concentration of sperm in ejaculate————————————— 21

2.5.7 Gases————————————————————————– 22

2.5.8 Bacterial Contaminants —————————————————– 22

2.6. Semen Quality Evaluation—————————————————- 22

2.6.1 Semen Colour—————————————————————- 24

2.6.2 Semen Volumes————————————————————– 25

2.6.3 Motility ———————————————————————– 27

2.6.4 Sperm Concentration——————————————————– 33

2.6.5 Normal and Abnormal Sperm———————————————- 35

2.6.6 Live Dead Sperm ———————————————————— 36

2.7 Biochemical Parameters——————————————————- 36

2.8 Basic Anatomy and physiology of the Hen’s Reproductive Tract— —- 38

2.8.1 Sperm Storage in Vivo—————————————————— 41

2.8.2 Behaviour of Sperm in the Oviduct of the Hen————————— 41

2.9 Artificial Insemination in Turkeys——————————————- 43

2.9.1 Artificial Insemination Techniques in Turkeys————————– 45

2.9.2 Advantages of Artificial Insemination ———————————— 46

2.9.3 Depths and Time of Insemination—————————————— 47

2.10 Fertility in Turkeys———————————————————– 48

2.10.1 Infertility in Turkeys——————————————————- 49

2.10.2 Factors that Affect Fertility in Turkeys Hens————————— 49

2.10.2.1 Factors influencing infertility in naturally mated hens————– 50

2.10.2.2 Infertility Syndrome —————————————————– 50

2.10.2.3 Age of the Hen———————————————————— 51

2.10.2.4 Mating Behaviour in Turkey Hens ———————————— 51

2.10.2.5 Effects of Body Weight of the Hen————————————- 53

2.10.2.6 Nutritional Causes of Infertility ————————————— 53

2.10.2.7 Influence of Disease on Fertility ————————————— 54

2.11.1 Infertility under Artificial Insemination ——————————– 54

2.11.2 Stress ———————————————————————— 54

2.11.3 Oviductal Environment of the Hen————————————— 55

2.11.4 Immunity against Sperm————————————————— 55

2.11.5 Semen Quality ————————————————————- 56

2.11.6 Number of sperm inseminated into the oviduct ———————— 56

2.11.7 Time of Insemination —————————————————— 57

2.12.1 Infertility in Males ——————————————————— 58

2.12.2 Body weight of Toms —————————————————— 58

2.12.3  Age ————————————————————————- 59

2.12.4  Male Mating Behaviour ————————————————– 59

2.13 Hatchability in Turkeys—————————————————— 61

2.13.1 Influence of temperature on Hatchability ——————————- 62

2.13.2 Relative Humidity ——————————————————— 63

2.13.3. Egg Shell Characteristics ————————————————- 63

2.13.4 Disease/Egg Contamination ———————————————- 64

2.13.5 Egg Storage —————————————————————– 64

2.13.6 Nutrition ——————————————————————– 65

2.13.7 Age of Hens —————————————————————- 65

2.13.8 Incubator setting and peculiar egg characteristics ——————— 65

2.13.9 Genetic factors affecting hatchability ———————————– 66

2.14 Candling and egg breakout ————————————————- 67

2.15 Systems of turkey management ——————————————– 68

2.15.1 Rearing systems in turkey production ———————————– 69

2.15.2 Semi-intensive management system ————————————- 69

2.15.1 Nutritional management under semi-intensive system—————– 71

2.16 Intensive management system ———————————————- 72

2.16.1 Nutritional management of turkey under intensive system———— 73

2.16.2 Vitamins and minerals requirements of turkeys———————— 76

2.16.3 Minerals ——————————————————————– 77

CHAPTER THREE: MATERIALS AND METHOD

3.1 Location of the Study———————————————————- 79

3.2 Plan of the Study————————————————————— 79

3.3 Duration of the Study———————————————————- 80

3.4 Procurement and management of experimental animals —————— 81

3.5 Pre-experimental Period/training of toms for semen collection ——— 83

3.6 Data collection: experiment I (Physical examination of semen)——— 83

3.7 Semen quality parameters measured—————————————– 84

3.7.1 Volume———————————————————————— 84

3.7.2 Progressive motility ——————————————————— 84

3.7.3 Live, Normal and Abnormal Spermatozoa ——————————- 85

3.7.4 Sperm concentration——————————————————– 85

3.8 Experiment 2: Artificial insemination, fertility and hatchability

     Trials—————————————————————————– 86

3.9 Egg collection, candling and hatching————————————— 89

3.10. Statistical analysis ———————————————————- 90

CHAPTER FOUR: RESULTS AND DISCUSSION————————— 91

CHAPTER FIVE: CONCLUSION AND RECOMMENDATIONS

CONCLUSION————————————– —- 114

Recommendation————————————————————– —- 116

References ———————————————————————        117
LISTS OF TABLES

Table 1: Effects of age and photoperiod on weekly sperm output of

toms (+ SE).———————————————————- —- 14

Table 2:  Daily sperm output of turkeys subjected to various frequencies

of semen collection (+ SE)—————————————- —- 20

Table 3: Semen volume of toms subjected to three frequencies of

semen collection.—————————————————— —- 26

Table 4 Semen volume of tomes subjected to seven frequencies of

semen collections—————————————————– —- 26

Table 5:Description of motility grades in farm animals/based

on scoring method —————————————————— —- 31

Table 6: Sperm motility (%) of toms subjected to various frequencies of

semen collection——————————————————- —- 32

Table 7: Mean percentage sperm motility of toms subjected to

various frequencies of semen collection ——————————– 32

Table 8: Sperm conc. of toms subjected to three frequencies of

semen collection.—————————————————— —- 34

Table 9: Sperm concentration of toms subjected to various

frequencies of semen collection (+ S E)————————– —- 34

Table 10: Recommended nutrient allowance for poultry under tropical

climatic condition—————————————————– —- 73

Table 11: Semen quality parameters of local turkeys under

intensive management system————————————— —- 75

Table 12: Semen parameters of turkeys fed with different protein levels      76

Table 13: Distribution of Experimental Animals to Treatments————– 81

Table 14: Nutrient Composition of the Breeder Diet per 100kg——— —- 82

Table 15: Lay out of experiment 1(semen evaluation) ——————- —- 83

Table 16: Insemination of Turkey hens based on frequency of

Semen Collection and rearing methods————————— —- 87

Table 17: Polling of semen from groups and pan for insemination

of hens————————————————————-       

Table 18: Mean ± SE of semen quality traits of toms ejaculated

at various frequencies under intensive and semi- intensive systems of management ——————————————————– —- 91

Table 19: Effect of Interaction between Management Systems and

Ejaculation Frequencies on Semen Quality Parameters of Local

Turkeys————————- —————————– ——-    

Table 20: Mean ± SE of fertility and hatchability of local turkeys under

intensive and semi- intensive systems of management ———–

Table 21: Effect of Interaction between Management Systems and

Ejaculation Frequency on Fertility and Hatchability Parameters

    of Local Turkeys—————————————————- —-

ABSTRACT

Two experiments were conducted to determine the effect of frequency of semen collection and management systems on semen quality, fertility and hatchability of local turkeys in the humid tropics. A total of 72 local Nigerian turkeys comprising 24 males and 48 females were used for the study at 36 weeks of age with average body weight of 9kg for the males and 4kg for the females. The males were randomly divided into two groups (1 and 2) with 12 males in each group. Group 1 males were intensively managed and fed 17% crude protein and 12.6 MJ/kg metabolizable energy breeder diet. Group 2 males were semi-intensively managed and subjected to free-range condition and given supplements. The males in both groups were subjected to four frequencies of semen collection (once, twice, three times and four times) weekly using abdominal massage technique. A total number of 286 ejaculates were collected and analyzed for volume, motility, sperm concentration, live sperm, normal sperm, abnormal sperm and total sperm in ejaculate. The forty eight hens were randomly divided into two groups (1 and 2) corresponding to the male groups, with 24 hens in both groups, 6 hens per each ejaculation frequency. The hens were sexually stimulated by ‘venting’ and inseminated with 0.25ml of semen weekly during late afternoon. A total number of 729 eggs were incubated and analyzed for fertility and hatchability.  The results showed that ejaculation frequency had significant (P < 0.05) effect on all the semen quality parameters measured. Two times per week semen collection yielded the highest ejaculate volume, sperm motility and normal sperm in both management groups compared to other ejaculation frequencies in both intensive and semi-intensive management systems respectively.  The semi-intensively managed toms had higher (P<0.05) mean values for motility, and live sperm. Sperm concentration values were similar among intensively and semi-intensively managed toms at all ejaculation frequencies. Abnormal sperm values were significantly (P< 0.05) highest in both groups under once per week ejaculation frequency and lowest in toms ejaculated twice per week. Increasing frequency of semen collection above twice per week decreased semen volume, sperm concentration and total sperm in ejaculate.  Increasing frequency of semen collection increased progressive motility percentage live sperm and abnormal sperm. There was no significant interaction (P > 0.05) effect between management system and ejaculation frequency on all semen quality, parameters measured. Fertility and hatchability results indicated significant (P <0.05) effect of ejaculation frequency on all parameters measured.  Percentage fertility ranged from 71.01 ± 2.65% to 92.18 ± 21.18. Out of a total number of 729 eggs incubated, 614 eggs were fertile. Percentage hatchability results obtained in this study ranged from 85.11 ± 4.20% to 100.00 ±0.00% in both management systems. There was no significant interaction (P > 0.05) between management systems and frequency of semen collection on fertility and hatchability of local turkey eggs.  It was concluded that two times per week collection frequency was ideal for local toms used for AI programmes while toms to be used can perform well in the programme under both management systems.

CHAPTER ONE

1.0 INTRODUCTION

1.1       Background of the Study

Food insecurity which is felt in most developing nations including Nigeria over the years has accentuated the already critical animal protein deficiency among human populations. High cost of livestock and poultry has limited the capacity of an average Nigerian to consume adequate quantity and quality of animal protein (Hamzat et al., 2003). Emeruwah (1999), and Ojewola, et al. (2004) prescribed massive production of animals with short reproduction cycles such as pigs, rabbits and poultry as the only remedy to the acute animal protein shortage in Nigeria. This however, has undoubtedly spurred research efforts in the direction of these animals that offer the highest turn-over rate and the quickest return on investment. Obviously, rabbit meat is not popular in Nigeria and its commercialization is limited by unknown factors. Pigs on the other hand suffer religious alienation. Thus, poultry has been the animal of choice (Sanni and Ogundipe, 2003). Although, production of local chicken is evident, large scale, medium scale and the back-yard poultry production enterprises are gaining ground in Nigeria as producers now mostly rear more productive exotic broiler and layer types of chicken which have shown considerable levels of adaptation to the prevailing environmental conditions.

            Okpeku, et al. (2003) noted that the exotic chickens require expensive inputs as a result of which, it is becoming increasingly difficult to sustain the poultry industry over the years under a poor economy .The prevalent high exchange rate of the naira to foreign currency needed for importation of parent stock and some feed ingredients not found locally is not helping matters. Onyimonyi and Onukwufor (2003) opined that the ban on importation of poultry meat and egg by Nigerian government may bring to an end the era of egg glut and low market for locally produced poultry meat and above all, encourage local production of chicken. Although, their assumptions appear to be the case, poultry meat and egg are apparently becoming ostentatious. The Smallholder Family Poultry Concept for Food Security and Poverty Alleviation in Nigeria has no doubt shown how other local poultry resources can improve rural livelihood (Sonaiya, 2002b). Therefore, the emphasis on the need to consider other poultry resources while combating animal protein shortage in Nigeria has formed the backbone of this study.

Turkey farming is very popular in the Western countries. The major producing countries are the United States of America, Germany, France, Italy, Netherlands and the United Kingdom. In 2004, the estimated world turkey meat production was 4.94 million tonnes (Central Poultry Development Organization, 2008). However, Nigeria’s contribution to the above statistic is not known. Commercial breeds and strains of turkeys such as Broad Breasted Bronze, Broad Breasted White, White Nicholas 300, Big-6, Hybrid Large White and a host of others have been developed by University Research Stations and reputable commercial turkey breeding companies in the Western world. Strong preference and elaborate research reports have been focused on these modern turkeys as a result of which they have been highly bred for intensive production. There are however, other types that thrive as scavengers under the extensive system of production practiced in localities of developing countries. They roam about, feeding on fresh grasses, insects, worms and snails. These genetically undeveloped, self-reliant, heat tolerant and rugged types are the least studied of all turkeys. Little effort has so far been directed at improving their productivity under free-range condition (Abeke and Ubani, 2008). Research reports on them are therefore scanty or non-existent (Zahraddeen, et al., 2005).

            Commercial turkey production in Nigeria is still rudimentary. The reason for this apparent low production seems to be due to lack of appreciation of its potential role in meat production and national economy or perhaps lack of understanding and knowledge of its management and production requirements (Abeke and Ubani, 2008). In Nigeria, turkey is a premium bird. Both local and exotic breeds are highly valued. Although some level of commercial production is evident, small stock-holder producers dominate the turkey industry. Commercial producers develop their flock structures with prolific exotic “broiler” strain. Back-yard and medium scale farmers operate with local types and exotic broiler strains in small flock units.

One of the major challenges facing turkey production in Nigeria and other developing countries is the low capability of the species to reproduce by natural mating. Breeders who rely on natural mating procedures often encounter poor results due to the clumsy nature of the toms as a reproductive partner. Modern turkey hens throughout the world are bred by artificial insemination. This is not because of the genetic merit to be gained, but primarily because the size and conformation of the male in terms of the extensive development of pectoral muscles arrived at during genetic selection for weight gain, culminated in diminished libido and reduced ability to perform during natural mating (Sexton, 1982; Burke, 1984). Burke (1984) further observed that modern toms lack the coordination and dexterity to accomplish sufficient mating to assure high fertility. Partial completion of the mating act even without transfer of semen to the female results in variable periods of sexual refractoriness during which time hens normally will not re -mate. The development of artificial insemination technology over the past decades has resulted in some significant advances in poultry breeding. The objective of artificial insemination programme is however not just to produce fertile eggs but to produce viable poults (Bakst, 1993). The US turkey industry relies on artificial insemination for the production of 300 million turkeys annually. Therefore, breeder fertility has been implicated to be of utmost importance to the overall success of the turkey industry. This is based on the realization that even the best incubators and hatchery management procedures cannot produce chicks from infertile eggs (Keith, 2008). In Nigeria, breeder flock produces high percentage of infertile eggs even with the recommended mating ratio of 1:16 adopted by farmer.

This study has therefore been designed to determine the effects of ejaculation frequency and management conditions on semen quality, fertility and hatchability of local turkey eggs in a humid tropical environment.

1.2       Statement of the Problem