Chinnadurai Pandian Shanmugam Selvan Robert Asha Rajini Monoharan Parthiban Kanniappan Karthickeyan Vol 7(9), 180-189 DOI- http://dx.doi.org/10.5455/ijlr.20170710032721
A study was carried out to assess the effect of semen collection interval and semen characteristics of ostriches aged four to nine years for a period of 12 months in tropical climate of India. The birds were grouped into two categories viz., four to six and seven to nine years-old. The artificial cloaca was used for semen collection. The ostriches were allowed to mate naturally by following the teaser technique. The overall mean values for semen collection interval, semen volume, pH, mass activity (score), spermatozoa motility, concentration, live and abnormal spermatozoa of ostrich were 17.36 days, 1.38 ml, 7.28, 4.26, 79.21 % , 2.69 ´ 109 per ml, 85.71 % and 15.30 % respectively. The individual males showed varied response and significant (P≤0.01) differences in all seminal attributes. The effect of age, month and season had significant (P≤0.01) influence on seminal attributes. The mean semen collection interval and semen characteristics in four to six year-old ostrich were better than seven to nine year-old ostrich. Overall, the vital seminal attributes like spermatozoa motility, concentration, live and abnormal spermatozoa were better during winter and summer than southwest and northeast monsoon seasons.
Keywords : Semen Collection Intervals Semen Characteristics Ostrich
Introduction
Ratite species such as ostrich (Struthio camelus), emu (Dromaius novaehollandiae) and rhea (Rhea americana) are fundamentally attractive for farming to produce leather, meat, oil and feathers. In India, ostrich was first imported by Tamil Nadu Veterinary and Animal Sciences University, in the year 2000 in order to find its adaptability in tropical climate and to find its suitability for Indian farming conditions. Unpredictable egg production, unstable fertility, poor hatchability and poor chick survival are some of the major constraints in viable ostrich farming (Hemberger et al., 2001). Worldwide, ostrich farming lacks structured breeding programs that would guarantee rapid genetic improvement for commercial utilization. Ostrich farming still relies on natural reproduction, leading to a major biological constraint due to the dominant influence of male-female pair bonding in the mating system (Malecki et al., 2008). To achieve rapid and sustained genetic improvement, ostrich farming needs to adopt advanced reproductive technological tools in semen collection, fertility assessment, semen handling and artificial insemination (Malecki and Martin, 2011). The assessment of semen collection interval and semen characteristics would be a valuable instrument for evaluating fertility level of male ostrich which will be useful in assisted reproductive technology. Hence, this study was carried out to assess the effect of age, month and season on semen collection intervals and semen characteristics of ostrich.
Materials and Methods
This experiment was carried out at Post Graduate Research Institute in Animal Sciences, Tamil Nadu Veterinary and Animal Sciences University, Kattupakkam, Kanchipuram district in Tamil Nadu, India during 2015. A total of nine adult male ostrich aged four to nine years were selected based on their phenotypic characters. To assess the age effect the nine ostriches were grouped into two age categories viz., four to six year (4 No.) and seven to nine year-old (5 No.). All the birds were housed under standard management conditions.
Semen Collection and Evaluation
The semen from each male ostrich was collected using artificial cloaca (AC) by following the teaser technique as described by Malecki and Martin (2005) and Rybnik et al. (2007). The semen collected from a total of nine individual male birds was evaluated for macroscopical and microscopical semen characteristics as per established procedure for domestic animals. The volume of the semen was measured directly by observing the marking on the collection tube with 0.1ml accuracy. The pH of the collected semen sample was analyzed as described by Rozenboim et al. (2003). The mass activity of the spermatozoa was estimated based on the wave motion. The activity was ranked on a 0 (no motility) to 5 scale (vigorus progressive movement, rapid edges) (Allen and Champion, 1955). The motility was assessed and expressed in percentage as described by Parker et al. (1942). The concentration of spermatozoa in fresh undiluted semen was determined by using a “NEUBAUER” type hemocytometer and the final concentration of spermatozoa expressed as millions (×109) per ml according to the procedure of Allen and Champion (1955). The viability of spermatozoa was determined by Eosin-Nigrosin staining procedure as described by Bakst and Cecil (1997) and abnormal spermatozoa were expressed in percentage as described by Alkan et al. (2002). The semen collected during a period of 12 months consequently were analysed to know the seasonal effects. The seasons were categorized as winter (January to February), summer (March to May), southwest (June to September) and northeast (October to December) monsoon (Indian Metrological Department, Pune, India).
Statistical Analyses
The effect of various sources of variation on semen collection interval and seminal attributes were analysed by One-way ANOVA as per the procedure of Duncan’s multiple comparison test (Duncan, 1955). Proportion data were converted to Arcsine values before ANOVA. Categorical data were analysed using Chi-square test. A value of P<0.05 was considered statistically significant. Statistical analyses were performed using SPSS 20.0 (SPSS Inc., Illinois, USA)
Results and Discussion
Semen Collection Interval and Semen Characteristics of Ostrich
The semen collection interval and semen characteristics of nine individual ostrich during the period of 12 month are presented in Table 1. Individual males showed significant (P≤0.01) difference in semen collection interval, with the mean interval of 17.36 days and the minimum and maximum semen collection interval of 10.16 days and 29.82 days. The semen collection interval over a period of 12 months varied between individual ostrich and showed significant (P≤0.01) difference in semen volume, colour and consistency. The mean semen volume was 1.38 ml. Semen colour ranged from creamy white (86.13 %) to white (13.86 %) and consistency ranged from thin (20.66 %) to thick (79.33 %). The pH of ejaculate showed no significance (P>0.05) difference among individual males. The mass activity score (4.26), spermatozoa motility (79.2 %), concentration (2.69 x109 per ml), live (85.71 %) and abnormal spermatozoa (15.30 %) showed significant (P≤0.01) difference among individual males and this values were comparable with the earlier findings of Bertschinger et al. (1992), Hemberger et al. (2001) and Ya-jie et al.(2001) in ostrich.
Effect of Age on Semen Collection Interval and Semen Characteristics
Effects of age on semen collection interval and semen characteristics of ostrich are presented in Table 2. Age of the birds showed significant (P≤0.01) influence on semen collection interval. The age group of four to six year-old ostrich showed better response (12.27 interval days) to semen collection than seven to nine year-old (20.61 interval days) ostrich. Age showed significant (P≤0.01) effect on volume, colour and consistency of semen. Significantly (P<0.01) higher semen volume was observed in four to six year-old ostrich (1.59 ml) than seven to nine year-old (1.18 ml) ostrich. Four to six year-old males produced significantly (P<0.01) higher percentage of creamy white and thick consistency of semen (93.87 and 82.56) than seven to nine year-old males (78.84 and 76.12, respectively) which indicates that the semen quality may decline with increasing age in ostrich. The mass activity, spermatozoa motility (%), concentration ( 109/ml), live and abnormal spermatozoa (%) showed significant (P≤0.01) difference among the age groups and the corresponding value in four to six year and seven to nine year-old ostrich were 4.38 and 4.12, 82.14 and 76.48, 2.90 and 2.49, 87.79 and 83.77; and 14.30 and 16.23, respectively, which are in accordance with the earlier findings of Bonato et al. (2010) and Rybnik et al. (2012) in ostrich.
Effect of Month on Semen Collection Interval and Semen Characteristics
The influences of month on semen collection interval and semen characteristics of ostrich are presented in Table 3. Month showed no significant difference in semen collection interval. However, numerically higher frequent semen collection was observed between February and August than between September and January. The semen volume obtained between April and August was higher than the volume between September and March which concurs with the earlier findings of Rozenboim et al. (2003) who has also reported significantly higher semen volume in ostrich between January and July than May and July. Effect of month on mass activity, spermatozoa motility, concentration and live spermatozoa observed in this study between January and June was higher than July and December, which agreed well with earlier findings of Rozenboim et al. (2003) and Rybnik et al. (2012) who have found that the semen quality in ostrich varied between months and significantly better quality between June and July than August and September.
Effect of Season on Semen Collection Interval and Semen Characteristics
Effect of season on semen collection interval and semen characteristics of ostrich are presented in Table4. The summer season had more frequent semen collection than winter and southwest monsoon. The less frequent semen collection observed during northeast monsoon concurs with findings of Rybnik et al. (2012) in ostrich who have observed less libido or poor cooperation during middle and at the beginning of the breeding seasons than peak season. The mean semen volume observed during winter, summer, southwest monsoon and northeast monsoon seasons showed significant (P<0.01) variation. The highest percentage of creamy white and thick consistency semen was observed during winter, followed by summer, southwest monsoon and northeast monsoon seasons. Significantly (P≤0.01) higher mass activity and spermatozoa motility was observed in semen collected during summer and winter seasons than southwest and northeast monsoon seasons. Similarly, spermatozoa concentration (x109/ml) and live spermatozoa (%) increased during northeast monsoon and reached the peak during winter season, then gradually declined during summer and southwest monsoon seasons, which concurs with the findings of Rybnik et al. (2008) in ostrich. The abnormal spermatozoa count showed a decreasing trend from winter to summer, then increasing trend towards southwest and northeast monsoon seasons. Similarly, Bertschinger et al. (1992) and Rozenboim et al. (2003) in ostrich observed more abnormal spermatozoa at the beginning and end of breeding season than mid season.
Table 1: Semen collection interval and semen characteristics (mean ± SE) of individual ostrich
Bird No. | Semen collection interval(days) | Semen characteristics | ||||||||||||
Semen volume
(ml) |
pH | Mass activity
Score (1-5) |
Sperm motility (%) | Sperm conc.
(×109/ml) |
Live
sperms (%) |
Abnormal spermatozoa (%) | Colour (%) | Consistency (%) | ||||||
Head | Tail | Total | Creamy white | White | Thick | Thin | ||||||||
01
(n=27) |
13.35ab± 1.90 | 1.24bc± 0.12 | 7.20a±0.06 | 4.52a± 0.09 | 84.07a± 1.22 | 2.80ab± 0.97 | 91.04a± 0.60 | 5.93a± 0.27 | 7.32a±0.32 | 13.26a± 0.49 | 100.00 | 0.00 | 100.00 | 0.00 |
02
(n=28) |
12.56a± 1.85 | 1.16bc± 0.96 | 7.16a±0.04 | 4.54a± 0.09 | 84.29a± 1.40 | 2.95ab± 0.10 | 89.47a± 0.76 | 6.81a± 0.36 | 7.62ab± 0.32 | 14.41ab± 0.58 | 100.00 | 0.00 | 100.00 | 0.00 |
03
(n=11) |
29.82c± 3.46 | 0.78c± 0.16 | 7.41ab±0.13 | 3.91bc± 0.09 | 69.09c± 0.91 | 1.99d± 0.12 | 80.41b± 1.29 | 7.34a± 0.45 | 9.41b±0.86 | 16.75b± 1.21 | 63.63 | 36.36 | 63.63 | 36.36 |
04
(n=23) |
15.32ab± 2.01 | 1.02bc± 0.12 | 7.26a±0.06 | 4.30ab± 0.09 | 79.13ab± 1.77 | 2.30bc± 0.13 | 87.55a± 1.21 | 7.13a± 0.29 | 8.36ab± 0.43 | 15.49ab± 0.66 | 73.91 | 26.08 | 70.00 | 30.00 |
05
(n=15) |
24.14bc± 6.25 | 1.63ab± 0.12 | 7.67b±0.12 | 2.67d± 0.12 | 51.25d± 1.80 | 1.77d± 0.07 | 58.43c± 1.16 | 11.54b± 0.60 | 13.59c± 0.59 | 25.12c± 1.11 | 20.00 | 80.00 | 25.00 | 75.00 |
06
(n=30) |
11.34a± 1.68 | 1.60ab ± 0.09 | 7.18±0.04 | 4.57a± 0.09 | 84.50a± 1.27 | 2.68ab± 0.10 | 89.35a± 0.89 | 6.58a± 0.34 | 8.16ab± 0.34 | 14.74ab± 0.65 | 93.33 | 6.66 | 93.33 | 6.66 |
07
(n=32) |
10.16a± 1.50 | 1.90a± 0.16 | 7.25a±0.05 | 4.38ab± 0.08 | 83.59a± 0.96 | 3.20a± 0.17 | 89.08a± 0.61 | 6.60a± 0.28 | 7.40ab ± 0.34 | 14.58ab± 0.54 | 100.00 | 0.00 | 90.15 | 9.85 |
08
(n=25) |
14.00ab ± 1.65 | 1.40abc± 0.11 | 7.22a±0.05 | 4.44a± 0.11 | 82.60a± 1.66 | 2.82ab± 0.14 | 88.67a± 1.08 | 6.58a± 0.43 | 7.68ab± 0.42 | 14.25ab± 0.80 | 92.00 | 8.00 | 91.00 | 9.00 |
09
(n=11) |
27.40bc± 3.62 | 1.10bc± 0.14 | 7.64±0.12 | 3.73c± 0.23 | 70.45bc± 1.88 | 2.81ab± 0.25 | 77.81b± 1.30 | 6.55a± 0.53 | 7.52ab ± 0.60 | 14.05ab± 1.09 | 81.81 | 18.18 | 81.88 | 18.18 |
Overall mean (n=202) | 17.3± 0.79 | 1.38± 0.05 | 7.28±0.02 | 4.26± 0.04 | 79.21± 0.85 | 2.69± 0.05 | 85.71± 0.73 | 7.02± 0.16 | 8.27± 0.18 | 15.30± 0.31 | 86.13±2.83 | 13.86±2.83 | 79.33±2.32 | 20.66±2.32 |
F value/ x2value | 3.732 | 6.855 | 6.187 | 23.459 | 26.931 | 9.551 | 39.936 | 14.576 | 16.384 | 18.805 | 78.69 | 79.25 | ||
Significance | (P<0.01) |
n=No. of ejaculate/bird; Means bearing different superscripts within the same column differ significantly
Table 2: Effect of age on semen collection interval and semen characteristics (mean ± SE) of ostrich
Age group | Semen collection interval(days) | Semen characteristics | ||||||||||||
Semen
volume (ml) |
pH | Mass activity
Score (1-5) |
Sperm motility (%) | Sperm conc.
(×109/ml) |
Live
sperms (%) |
Abnormal spermatozoa (%) | Colour | Consistency | ||||||
Head | Tail | Total | Creamy white | White | Thick | Thin | ||||||||
4-6 year
(n=98) |
12.27
± 0.93 |
1.59
± 0.07 |
7.26
±0.03 |
4.38
± 0.06 |
82.14
± 0.94 |
2.90
± 0.08 |
87.79
± 0.80 |
6.58
± 0.18 |
7.71
±0.20 |
14.30
± 0.35 |
93.87 | 6.12 | 82.56 | 17.43 |
7-9 year
(n=104) |
20.61
± 1.05 |
1.18
± 0.06 |
7.29
±0.03 |
4.12
± 0.07 |
76.48
± 1.32 |
2.49
± 0.06 |
83.77
± 1.17 |
7.43
± 0.24 |
8.80
±0.28 |
16.23
± 0.50 |
78.84 | 21.15 | 76.12 | 23.87 |
Overall mean
(n=202) |
17.36
± 0.79 |
1.38
± 0.05 |
7.28
±0.02 |
4.26
± 0.04 |
79.21
± 0.85 |
2.69
± 0.05 |
85.71
± 0.73 |
7.02
± 0.16 |
8.27
±0.18 |
15.30
± 0.31 |
86.13
±2.83 |
13.86
±2.83 |
79.33
±2.32 |
20.66
±2.32 |
F value /
x2 value |
29.911 | 21.306 | 0.267 | 7.450 | 13.634 | 17.330 | 8.297 | 8.917 | 10.617 | 11.361 | 9.548 | 10.117 | ||
Significance | ** | ** | NS | ** | ** | ** | ** | ** | ** | ** | ** | ** |
n=No. of ejaculate/age group; ** (P<0.01); NS- Not significant.
Table 3: Effect of month on semen collection interval and semen characteristics (mean ± SE) of ostrich
Months
(2015) |
Semen collection interval(days) | Semen characteristics | ||||||||||||
Semen volume
(ml) |
pH | Mass activity
Score (1-5) |
Sperm motility (%) | Sperm concentration
(×109/ml) |
Live
sperms (%) |
Abnormal spermatozoa (%) | Semen colour
(%) |
Semen consistency (%) | ||||||
Head | Tail | Total | Creamy white | White | Thick | Thin | ||||||||
January
(n=20) |
17.66
± 1.86 |
1.32ab
± 0.16 |
7.20
±0.07 |
4.45abc
± 0.15 |
82.00abc
± 2.57 |
3.14ab
± 0.16 |
86.87abc
± 1.99 |
7.05ab
± 0.48 |
7.96ab
± 0.56 |
15.02ab
± 0.98 |
96.79 | 3.21 | 90.38 | 9.62 |
February
(n=18) |
15.77
± 2.75 |
1.08b
± 0.11 |
7.14
±0.05 |
4.72ab
± 0.13 |
85.56ab
± 2.45 |
3.26a
± 0.16 |
89.61ab
± 2.17 |
6.15ab
± 0.35 |
7.77ab
± 0.61 |
13.92ab
± 0.91 |
97.36 | 2.63 | 90.73 | 9.26 |
March
(n=18) |
15.95
± 2.07 |
0.97b
± 0.10 |
7.19
±0.06 |
4.77a
± 0.10 |
87.22a
± 1.29 |
2.83abc
± 0.08 |
91.70a
± 0.71 |
5.78a
± 0.36 |
7.19a
± 0.25 |
12.97a
± 0.51 |
93.26 | 6.74 | 85.51 | 14.49 |
April
(n=18) |
16.68
± 2.46 |
1.52ab
± 0.18 |
7.17
±0.06 |
4.83a
± 0.09 |
87.22a
± 1.35 |
3.18ab
± 0.08 |
92.00a
± 0.86 |
5.70a
± 0.22 |
7.01a
± 0.36 |
12.71a
± 0.48 |
95.24 | 4.76 | 86.23 | 13.77 |
May
(n=23) |
12.81
± 3.64 |
1.46ab
± 0.18 |
7.22
±0.07 |
4.43abc
± 0.17 |
82.17abc
± 2.88 |
2.68abc
± 0.12 |
87.66abc
± 2.45 |
6.43ab
± 0.29 |
7.80ab
± 0.48 |
14.23ab
± 0.75 |
94.91 | 5.08 | 85.22 | 14.78 |
June
(n=16) |
19.60
± 2.23 |
1.87a
± 0.11 |
7.34
±0.11 |
4.12abc
± 0.15 |
77.50abcd
± 2.96 |
2.29c
± 0.10 |
85.29abc
± 2.77 |
6.43ab
± 0.36 |
7.84ab
± 0.48 |
14.18ab
± 0.76 |
81.02 | 18.98 | 72.51 | 27.49 |
July
(n=19) |
15.58
± 1.96 |
1.60ab
± 0.09 |
7.32
±0.07 |
3.85c
± 0.10 |
74.00cd
± 2.45 |
2.19c
± 0.08 |
83.13abc
± 2.38 |
6.76ab
± 0.43 |
7.91ab
± 0.49 |
14.67ab
± 0.90 |
82.41 | 17.59 | 72.38 | 27.62 |
August
(n=11) |
08.00
± 3.46 |
1.30ab
± 0.18 |
7.27
±0.14 |
3.81c
± 0.18 |
73.31cd
± 1.82 |
2.24c
± 0.17 |
80.70bc
± 1.58 |
8.44bc
± 0.64 |
9.51ab
± 0.91 |
17.95bc
± 1.40 |
82.32 | 17.68 | 73.16 | 26.84 |
September (n=13) | 20.50
± 2.81 |
1.15ab
± 0.20 |
7.46
±0.09 |
3.92c
± 0.21 |
75.36bcd
± 3.51 |
2.41bc
± 0.25 |
81.23bc
± 2.12 |
7.44abc
± 0.66 |
8.14ab
± 0.83 |
15.58abc
± 1.39 |
81.35 | 18.64 | 72.66 | 27.33 |
October
(n=11) |
23.06
± 2.60 |
1.18ab
± 0.17 |
7.45
±0.08 |
3.72c
± 0.19 |
74.09cd
± 2.41 |
2.27c
± 0.19 |
80.69bc
± 1.81 |
7.66abc
± 0.77 |
9.06ab
± 0.72 |
16.73abc
± 1.19 |
70.39 | 29.61 | 71.29 | 28.77 |
November (n=18) | 18.95
± 2.70 |
1.37ab
± 0.21 |
7.42
±0.11 |
3.77c
± 0.17 |
70.83d
± 3.29 |
2.96abc
± 0.31 |
80.67bc
± 3.41 |
8.23bc
± 0.58 |
9.59ab
± 0.63 |
17.82bc
± 1.15 |
72.41 | 27.59 | 70.58 | 29.42 |
December (n=17) | 19.28
± 2.51 |
1.58ab
± 0.12 |
7.32
±0.07 |
4.00bc
± 0.14 |
75.88bcd
± 3.10 |
2.33c
± 0.18 |
82.83abc
± 2.28 |
9.43c
± 0.73 |
10.53b
± 0.80 |
19.96c
± 1.39 |
71.73 | 28.26 | 69.56 | 30.44 |
Overall mean (n=202) | 17.36
± 0.79 |
1.38
± 0.05 |
7.28
±0.02 |
4.26
± 0.04 |
79.21
± 0.85 |
2.69
± 0.05 |
85.71
± 0.73 |
7.022
± 0.16 |
8.27
± 0.18 |
15.30
± 0.31 |
86.13±2.83 | 13.86±2.83 | 79.33±2.32 | 20.66±2.32 |
F /x2 value | 1.797 | 2.536 | 1.753 | 7.246 | 6.451 | 6.801 | 4.299 | 5.578 | 3.284 | 4.833 | 24.75 | 27.32 | ||
Significance | NS | ** | NS | ** | ** | ** | ** | ** | ** | ** | ** | ** |
n=No. of ejaculate/month; Means bearing different superscripts within the same column differ significantly; ** (P< 0.01); NS- Not significant.
Table 4: Effect of season on semen collection interval and semen characteristics (mean ± SE) of ostrich
Semen collection interval(days) | Semen characteristics | |||||||||||||
Season | Semen volume | pH | Mass activity | Sperm motility (%) | Sperm conc. | Live | Abnormal spermatozoa (%) | Semen colour | Semen consistency (%) | |||||
(ml) | Score | (×109/ml) | sperms | (%) | ||||||||||
(1-5) | (%) | Head | Tail | Total | Creamy white | White | Thick | Thin | ||||||
Winter | 16.76ab | 1.21b ± 0.10 | 7.17a | 4.57a | 83.68a | 3.20a | 88.17a | 6.63ab | 7.87a | 14.50ab | 97.36 | 2.63 | 90.73 | 9.26 |
(Jan-Feb) | ± 1.62 | ±0.05 | ±0.10 | ± 1.71 | ±0.11 | ± 1.57 | ± 0.32 | ±0.38 | ± 0.36 | |||||
(n= 38) | ||||||||||||||
Summer | 14.98a | 1.33ab | 7.19 | 4.66a | 85.25a | 2.88b | 90.20a | 6.01a | 7.37a | 13.38a | 94.91 | 5.08 | 85.22 | 14.78 |
(March-May) | ± 1.69 | ± 0.10 | ±0.04 | ±0.08 | ± 1.37 | ±0.09 | ± 1.26 | ± 0.26 | ±0.21 | ± 0.53 | ||||
(n= 59) | ||||||||||||||
Southwest | 17.83ab | 1.52a | 7.35 | 3.93b | 74.83b | 2.27d | 82.59b | 7.10b | 8.23a | 15.34b | 81.35 | 18.64 | 72.66 | 27.33 |
monsoon | ± 1.30 | ± 0.08 | ±0.04 | ±0.08 | ± 1.36 | ±0.09 | ± 1.25 | ± 0.26 | ±0.31 | ± 0.52 | ||||
(June-Sep) | ||||||||||||||
(n= 59) | ||||||||||||||
Northeast | 20.18b | 1.40ab | 7.39b | 3.85b | 73.48b | 2.57c | 81.00b | 8.54c | 9.81b | 18.35c | 71.73 | 28.26 | 69.56 | 30.44 |
monsoon | ± 1.51 | ± 0.10 | ±0.05 | ±0.09 | ± 1.86 | ±0.10 | ± 1.63 | ± 0.39 | ±0.35 | ± 0.60 | ||||
(Oct-Dec) | ||||||||||||||
(n= 46) | ||||||||||||||
Overall mean | 17.36 | 1.38 | 7.28 | 4.26 | 79.21 | 2.69 | 85.71 | 7.02 | 8.27 | 15.3 | 86.13 | 13.86 | 79.33 | 20.66 |
(n=202) | ± 0.79 | ± 0.05 | ±0.02 | ±0.04 | ± 0.85 | ±0.05 | ± 0.73 | ± 0.16 | ±0.18 | ± 0.31 | ±2.83 | ±2.83 | ±2.32 | ±2.32 |
F value / | 2.095 | 2.218 | 5.164 | 23.22 | 16.35 | 16.48 | 9.261 | 14.293 | 9.785 | 13.571 | 16.938 | 17.241 | ||
x2 value | ||||||||||||||
Significance | * | * | ** | ** | ** | ** | ** | ** | ** | ** | ** | ** |
n=No. of ejaculate/season; Means bearing different superscripts within the same column differ significantly; ** (P< 0.01); * (P< 0.05)
Conclusion
From the above study it is concluded that, semen collection interval and semen characteristics in ostrich were variable between individual males, months and seasons and all the semen quality parameters were better during more frequent semen collection. Further, significantly better semen attributes observed during summer and winter than southwest and northeast monsoon seasons suggested that, summer and winter seasons will be suitable to get more number of semen collection in ostrich.
Acknowledgements
The authors are highly thankful to Dean, Madras Veterinary College, Chennai-07 and Hon’ble Vice chancellor, Tamil Nadu Veterinary and Animal Sciences University for providing all the necessary support and facilities for conducting this doctoral study.
References