Keywords (Extracted from title, table of contents and
abstract of thesis) Camel, Breeding, Morphological,
Pakistan, Temperature, Testis, Ecology, Ultrasonic, Rutting, Humped,
Dromedarius, Functional, Punjab,natural |
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Abstract Present study was
conducted during four seasons of the year, 2008 namely winter
(December to February), spring (March to April), summer (May to
September) and autumn (October to November). The study was divided
into two phases; in first phase a questionnaire survey was conducted
on traditional management system of camels and climatic data was
collected from three ecological zones under study (Faisalabad,
Bhakkar and Attock). In second phase, total 24 mature healthy male
camels were used for recording seasonal and ecological changes in
the behavior, ultrasonographic structure and biometry of testis and
serum biochemistry (steroid hormones and some minerals) at allthe
zones. Biopsy sampling was done from the camels kept at Faisalabad
zone (n=12; 6 in each breeding and non-breeding season) for
ultastructural investigations, and slaughterhouse sampling (n=24; 6
sample in each season of the year) was done for morphometrical
studies.
The period of sexual activity started earlier in November and
extended more even up to April at Attk as compared to other zones.
Male camels used for breeding even up to 20 years of age at Attk
zone. Duration of copulation was up to even 35 min at Attk zone, so
it can be derived that the males of Attk zone are more efficient in
reproduction as compared to FSD and Bkkr. The degree of most of
rutting behavioral signs varies among different seasons and climate
of the location. Some behavioral signs were observed as more
extensive at Attk and then Bkkr zone as compared to the FSD, in the
autumn (October, November) and spring seasons of the year, which
revealed that the rutting season started earlier at these locations
(Attk and Bkkr) and extended even up to the start of the summer at
Attk zone. Biometric studies showed significantly (P<0.01) higher
scrotal length and width of the testis during winter and spring
season as compared to summer and autumn. Ultrasonographic imaging
showed, the parenchyma of the testis as homogenous and moderate
echogenic, the testicular capsule was appeared as thick hyper-echoic
structure and tunics were identified as hyperechoic lines in both
longitudinal and transverse planes, covering the parenchyma. A thin
intratunical anechoic linear area was identified, because of fluid
between the connective tissue coverings. Mediastinum was visualized
as hyperechoic central line in the longitudinal section and a
centralhyperechoic circular area in transverse plane of the testis.
Season had a prominent noticeable effect on the ultrasonic picture
of the testis and epididymis at all the experimental zones. Serum
testosterone was higher (P<0.01) during the winter season at all
ecological zones under study, it started decreasing during spring
and reached baseline
during summer, maintained almost same during autumn at FSD zone
however increased again in autumn at Attk and Bkkr zones.This
increased level in autumn season was more at Attk as compared to
Bkkr zone. Serum estradiol 17- β was higher (P<0.01) during the
cooler months including January, February at all the ecological
zones, it started declining in the month of March, April and May,
little increased level was observed in the month of June but again
sloped down in July and remained on baseline in the months of
August, September, October and November. Serum concentrations of
calcium, iron, sodium and chloride were higher (P<0.01) during the
winter and spring as compared to other seasons of the year, while
vice versa was true for the serum potassium, as it was recorded as
significantly higher during the summer season. Serum testosterone,
estradiol, calcium, iron, sodium and chloride were negatively
correlated with the average environmental temperature and rainfall
while positively correlated with the relative humidity and vice
versa for serum potassium levels with some regional variations among
different zones.
Morphometrical studies showed that the volume, weight of the testis,
average diameter of Sertoli cells, volume of intertubular
compartment, relative volume of Leydig cells (VLc %), total volume
of Leydig cells (TVLc × 1012μm3), numbers of Leydig cells ×109 per
testis and % intertubular tissue in the parenchyma of testis, were
significantly (P<0.01) higher during the winter and spring seasons
as compared to summer and autumn. However, % area occupied by the
seminiferous tubules, % seminiferous tubule / interstitium, and the
volume occupied by the seminiferous tubules and diameter of
seminiferous tubules were recorded as significantly (P<0.01) higher
during summer and autumn as compared to winter and spring seasons.
Ultrastructural studies showed highly active Leydig and Sertoli
cells during breeding season of camels (cytoplasm was having
abundant and developed smooth endoplasmic reticulum (SER), more oval
to elongate mitochondria and few fat droplets) and vice versa during
the non-breeding season. |