| Livestock Research for Rural Development 18 (3) 2006 | Guidelines to authors | LRRD News | Citation of this paper |
The effect of human menopausal gonadotropin (pergonal ®) on semen characteristics of Nigerian local cocks was studied. Twenty-five clinically healthy and mature cocks, weighing between 1.5 and 1.6kg were allocated randomly to five treatment groups. Sperm quality (expressed as progressive motility and percentage of morphologically normal/abnormal sperm cells) and sperm quantity (expressed as sperm concentration, and semen volume) were the parameters evaluated in each cock.
The highest percentage sperm motility and percentage live sperm cells were observed when a dose of 24.0 IU was administered. As compared with the control, the effect of the gonadotropin on semen concentration was positive.
The results of this study indicate that human menopausal gonadotropin increases fertility of Nigerian local cocks.
Key words: local cocks, Nigerian, Pergonal®, semen
Nigerian local chickens have small body size, poor growth, small egg size and poor reproductive performance. These characteristics make them an undesirable stock in a "competitive economic situation" (Oguike et al 2000). However, the local chickens hold some potentials if their reproductive performances can be improved. Improvement in reproduction of the local cocks is crucial to the socio-economic status of Nigerian rural dwellers. Natural hormones or their analogues are some of the ways of improving the reproductive performances of farm animals. Since the first experimental induction of super ovulation was reported by Casida et al (1943), several commercial preparations of gonadotropins have been used in super ovulatory protocols. Human menopausal gonadotropin (Pergonal ® ) is one of such preparations that induces ovulation in domestic animals (Sugano et al 2001; Lauria et al 1982). Pergonal® is a lyophilized gonadotropin and a preparation of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a ratio of 1:1.
Although, there are research findings on semen evaluative parameters in cocks (Ezekwe et al 2003; Oguike et al 2000; Egbunike and Oluyemi 1979), there is little or no information on the effect of human menopausal gonadotropin on semen characteristics (quantity and quality) of Nigerian local cocks.
Twenty-five mature local cocks were purchased from an open market and housed individually in cages. The birds were dewormed, vaccinated and fed commercial grower's ration. Water was provided ad libitum. During the pre-experimental period that lasted three weeks, cocks were trained twice daily (morning and evening) for semen collection by the massage technique.
The cocks were assigned randomly to five treatment groups consisting of five birds per group. The treatment groups are as follows:
Group A - Each bird received 1.0ml physiological saline
solution. This serves as the control.
Group B - 0.08ml Pergonal® (equivalent to 6.0 I.U
of FSH and LH) was administered to each cock.
Group C - 0.16ml Pergonal® (equivalent 12.0 I.U FSH
and LH) was administered to each cock.
Group D - 0.24ml Pergonal® (equivalent to 18.0 I.U
FSH and LH) was administered to each cock.
Group E - 0.32ml Pergonal® (equivalent to 24.0 I.U
FSH and LH) was administered to each cock.
During the experiment, a vial containing 75 I.U FSH and 75 I.U LH was dissolved in 1ml of physiological saline solution. Thus, different doses of Pergonal® were administered intramuscularly for three consecutive days for three weeks.
Each cock was ejaculated twice a week (Monday and Thursday) between 9.00 to 10.00 hours throughout the duration of the experiment.
Semen collection was done by the abdominal massage technique and the manipulation of cloaca as described by (Burrows and Quinn 1937}. Ejaculates were collected weekly from each cock for the period of eight weeks.
Semen evaluation involved determination of ejaculate volume, colour, viscosity, sperm motility and concentration. Sperm motility was recorded in percentage according to Okere (1983) and Umesiobi and Iloeje (1999). Sperm concentration was estimated by haemocytometer counts as described by Iheukwumere and Okere (1990). Sperm morphology was assessed by differential staining according to White (1971).
Data on ejaculate characteristics were subjected to analysis of variance according to the procedure described by Steel and Torrie (1980).
As shown in Table 1, semen volume was highest when 6.0 I.U and 12.0.I.U of Pergonal® were administered. The increase in volume was highly significant (P<0.01) in weeks 2 and 3. The response of individual birds to dosage level varied differently. Values of semen volume in the present study are consistent with the values reported by Oguike et al (2000) and Ezekwe et al (2003), but slightly lower than the normal range of values given by Laing et al (1988).
|
Table 1. Effects of week, animal and dosage on semen characteristics of nigerian local cocks treated with Pergonal® |
|||||
|
|
Volume, ml |
Motility, |
Live sperm cells, % |
Abnormal/dead sperm cells, % |
Sperm concentration, |
|
Range |
0.13-0.50 |
48.3-57.3 |
44.2-54.5 |
15.7-21.1 |
1.98-2.47 |
|
Week 1 |
0.26a |
55.6a |
53.6a |
20.9a |
2.01a |
|
Week 2 |
0.27 a |
53.6b |
51.0b |
19.1b |
2.07 a |
|
Week 3 |
0.26 a |
57.3b |
52.2b |
15.7c |
2.08 a |
|
S.E.M ± |
0.003 |
- |
- |
0.24 |
- |
|
Animal 1 |
0.26a |
54.7c |
53.4a |
18.1 |
2.00a |
|
Animal 2 |
0.27 a |
55.6 a |
51.9b |
18.6a |
2.07 a |
|
Animal 3 |
0.28 a |
55.2 a |
52.0b |
18.9b |
2.07 a |
|
Animal 4 |
0.24 a |
56.3b |
52.0b |
18.9 a |
2.09 a |
|
Animal 5 |
0.26 a |
55.5 a |
52.1b |
18.2 a |
2.08 a |
|
S.EM. ± |
0.004 |
0.41 |
0.22 |
0.31 |
0.02 |
|
Control |
0.26 a |
56.1 a |
51.1 a |
21.1 a |
2.09 a |
|
6.0 IU |
0.30b |
54.2b |
52.8b |
17.6c |
2.07 a |
|
12.0 IU |
0.31b |
54.8b |
50.8 a |
18.1b |
2.06 a |
|
18.0 IU |
0.20c |
55.7c |
52.2b |
18.2b |
2.04 a |
|
24.0 IU |
0.24 a |
56.5 a |
54.5c |
17.8c |
2.00 a |
|
SEM ± |
0.004 |
0.41 |
0.22 |
0.31 |
0.018 |
|
a, b, c, values with different superscripts in a column within main effects are different (P<0.05) |
|||||
The values for percentage of motile spermatozoa ranged from 48.3 to 57.3%. These are in agreement with the values given by Oguike et al (2000), but lower than the values reported by Ezekwe et al (2003). Percentage of motile spermatozoa was highest (P<0.01) when 24.0 IU of the gonadotropin was administered. Cold shock could not have been responsible for the relatively low motility observed when lower doses of the hormone were administered because estimation of the progressive motility was done soon after semen collection.
The sperm concentration range of 1.98 - 2.10 x 109/ml compares favourably with the reports of Ezekwe et al (2003) who recorded 2.02 x 109/ml. The present values are also in agreement with the value (2.0 x 109/ml) given by Keskin et al (1997), but lower than the value (3.8 x 109/ml) reported by Chalov (1970). However, Oguike et al (2000) reported a lower value (1.18 x 109/ml). As shown in Tables 1 and 2, sperm concentration varied from one cock to another. The dosage effect on sperm concentration was significant (P<0.05).
|
Table 2. Analysis of variance of semen characteristics |
||||||
|
Source of variation |
d.f |
Semen volume, % M.S |
Motility, % M.S |
Live sperm cells, % M.S |
Abnormal/dead sperm cells, % M.S |
Sperm concentration , x 109/ml M.S |
|
Dosage |
4 |
0.062914*** |
26.67*** |
65.05*** |
61.05*** |
0.038756** |
|
Animal |
4 |
0.0060923*** |
10.53n.s |
11.54** |
3.89n.s |
0.042732** |
|
Weeks |
2 |
0.001752* |
172.09*** |
85.81*** |
348.38*** |
0.063249** |
|
Weeks x Animal |
8 |
0.0003428n.s |
7.54n.s |
5.26** |
7.03* |
0.007523n.s |
|
Weeks x Dosage |
8 |
0.0011520* |
16.81** |
118.91*** |
24.70*** |
0.010324n.s |
|
Animals x Dosage |
16 |
0.0216803*** |
4.46n.s |
13.77*** |
3.20n.s |
0.016447* |
|
Week x Animal |
32 |
0.0011095** |
4.43n.s |
3.75*** |
4.03n.s |
0.001708n.s |
|
Error Residual |
75 |
0.0005080 |
5.13 |
1.48 |
2.88 |
- |
The percentage normal sperm cells, 44.2 to 59.2%, in the present study, is low compared to the value (79.2%) given by Oguike et al (2000). The percentage of live sperm cells was highest (54.5%) when 24.0. IU of Pergonal® was injected. It is suggested that high live sperm cells are expected to lead to high fertility.
The percentage abnormal/dead sperm cells (20.0 to 22.5%) in the present study compared favourably with the findings (17.1 - 20.8% for normal, naked neck and frizzle strains of cocks) of Oguike et al (2000). It was observed that at weeks 2 and 3, percentage of abnormal/dead sperm cells was low (19.1, 15.7%) compared with the control (20.9%). It was also observed that increased doses of Pergonal® resulted in decreased percentage of abnormal/dead sperm cells.
The results of this study indicate that Pergonal® administered intramuscularly to Nigerian local cocks increases sperm volume, concentration, motility, live sperm cells and reduces the percentage abnormal/dead sperm cells and so increases fertility in this species of birds.
Burrows W H and Quinn J P 1937 The collection of spermatozoa from the domes6ic fowl and turkey. Poultry Science 16:19-24.
Casida L E,Meyer R V, Mcshan W H and Wisnicky W 1943 Effects of pituitary gonadotropins on the ovaries and on the induction of super ovulation in cattle, American Journal of Veterinary Research 4: 76-94 .
Chalov A 1970 Semen quality and fertilizing capacity of cocks. Ptiferodstron 20(1):24-26
Egbunike G N and Oluyemi A 1979 Comparative studies of the reproductive capacity of Nigerian and exotic poultry breeds. Nigerian Journal of Animal Production 6:47-57.
Ezekwe A G, Udozor I J and Osita C O 2003 Effects of quantitative feed restriction on semen quality of Nigerian local cocks. Nigerian Journal of Animal Production 30(1):127-132.
Iheukwumere F C and Okere C 1990 Effect of frequent ejaculations on semen characteristics of Nigerian Yankasa rams. Small Ruminant Research. 3:77-83.
Keskin O, Tekin N and Akeay E 1997 The principal sperm characteristics of Denizli cocks. Animal Breeding Abstract 65:369.
Laing J A, Morgan W J B and Wagner W C 1988 Fertility and infertility in domestic animals. 4th edition, Baillière Tindall London. Pp 39-51.
Lauria A, Olivia O, Genazzan A R, Cremonesi F, Crotti S and Barbett M 1982 Improved method to induced super ovulation in cattle using human menopausal gonadotrpin (HMG).Theriogenology 18:357-364.
Oguike M A, Ndubueze A N and Ibe S N 2000 Semen quality of different genotypes of Nigerian local cocks. Journal of Sustainable Agriculture and Environment 2(2):310-313.
Okere C 1983 Semen characteristics of West African dwarf goats kept in the Netherlands. M. Phil. Thesis, University of Ife, Nigeria. 98 pp.
Steel G O and Torrie J H 1980 Principles and procedure of statistics. McGraw Hill. New York.
Sugano M, Shinogi T, Nakada K and Nakao T 2001 Endocrine profiles and embryo quality in Japanese black cattle superovulated with human menopausal gonadotropin and porcine follicle stimulating hormone. Reproduction in Domestic Animals Volume 36 (29) 57
Umesiobi D O and Iloeje M U 1999 Effect of sexual teasing and diurnal period of semen collection on reaction time and semen characteristics of large white boars. Journal of Sustainable Agriculture Environment 2:231-235.
White I G 1971 Physiology of mammalian semen: In: Reproduction in Farm Animals. 3rd edition. E S Hafez (editor). Philadelphia Lea and Febiger. Pp 113-114.
Received 7 July 2005: Accepted 14 January 2006; Published 22 March 2006