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Register a new userGenetiC evaluation of holsteiN cattle for incidence of mastitis
التقويم الوراثي لماشية الهولشتاين لمقاومة الإصابة بالتهاب الضرع
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Damascus University ورقة بحثية
Publication date
2004
fields
Animal Production
and research's language is
العربية
Created by
Shamra Editor
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تم تحليل 10159 سجلا عائدًا ل 3116 بقرة هولشتاين للمدة من 1998-2001 في محطة النصر التابعة للشركة المتحدة للثروة الحيوانية المحدودة في الصويرة، استنبط دليل مقاومة التهاب الضرع لكل بقرة معتمدًا على مدة الإصابة و عدد الأرباع المصابة و وقت الإصابة من بداية الحلب لتقويم أفراد القطيع وراثيًا وفق هذا الدليل و لإنتاج 305 أيام من الحليب.
At the Nasr Dairy Cattle Station , United Company for Animal Resources Ltd., and over the period from 1998 to 2001, 10159 records produced by 3116 Holstein cows were analysed statistically. An index for the resistance to mastitis was derived for each cow depending on the duration and time of infection, and the number of quarters infected. A genetic evaluation of the Holsteins at the Station as to their resistance to mastitis and 305-day milk yield was attempted.
References used
Blair, H. T. and Pollak, E. J. 1984. Estimation of genetic trend in a selected population with and without the use of a control population . J. Anim. Sci. 58 : 878-886
Catillo, G., Kadlecik, O. and Moioli, B. 1995. Genetic evaluation of selected Holstein population with an animal model for milk production. Zivocisna Vyroba, 40 (12): 529-532
Falconer, D. S. 1989. Introduction to Quantitive Genetics .3rd edition, Longman House, London
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This study was conducted at Fedio Dairy Station using 2189 records for 790
Holstein cattle to study the effect of frozen–thawed bull semen, inseminator,
calving year (CY), calving season (CS) and parity (P) on the number of services
per conception
(S/C). Data were obtained between the period 2003 and 2013
and evaluated according to GLM procedure (SAS 9). Analysis of variance was
used to determine the effect of studied factors on S/C.
This study was conducted at fedio dairy station belongs to the General organization
for cattle in Lattakia.. A total of 2534 production records of 1771 Holstein cattle were used
to study factors affecting the Days open (DO) during 1990 to 2013, and
to study the effects
of calving year, calving season, parity and interactions between studied factors on this trait.
Data were analyzed by the Least Square Means, and Duncan test was used to compare
means by SAS 9 program.
The overall mean for Days Open (DO) was 150.23 ± 1.44 days. and affected
significantly (P< .0..1) by calving year, calving season, parity and interaction (calving
year × calving season), (calving year × calving season) and (P<.0.5 ) by interaction
(calving year × calving season × parity) on the Days Open, but there was no significant
effect for interaction (calving year × parity).
Results suggested that better management, and improving the feeding status may
reduce Days Open to typical period (60 - 90 days), reduce interval calving, to get calf
every year, and increase reproductive and economic efficiency of dairy cattle at fedio
station.
This study was conducted at Kharabo Dairy Station belongs to the Faculty
of agriculture, University of Damascus. 553 records for 206 Holstein Friesian
cattle were used to study factors affecting the calving interval during 1982 to
2007. Data were
exposed eccording to GLM, and analysis of variance was used
to determine the calving interval (CI) and the effect of calving year, calving
season, parity and interactions on the calving interval, and Duncan test was
used to compare means by SPSS program. The overall mean for (CI) was
459.12±4.90 days. and affected significantly (0.001>P) by calving year, but
there was no significant effect for calving season, parity and interactions
between studied factors on the calving interval. These results suggested that
better management, and applaying more efficient administration practices as
well as to improving the feeding status may reduce calving interval to typical
period of 365 days and increase reproductive and economic efficiency of dairy
cattle at Kharabo station.
This study was conducted at Kharabo dairy station belongs to the Faculty of
Agriculture، University of Damascus. 692 productive records for 269 Holstein
Friesian cattle were used to study the effects of calving year, age at first calving،
calving
season and parity on the adjusted 305-day milk yield. Data were
exposed to GLM, analysis of variance was applied to determine the effect of
studied factors and differences between averages were compared according to
Duncan test using SPPS 17. The overall mean for (305-d milk) was 6222.6 ±
62.01 kg. and affected significantly (P < 0.001) by calving year and parity and
(P<0.05) by age at first calving. No significant effect for season was observed.
Results suggested that better management practices and improving the feeding
status might help increasing the 305-d milk and making the status more
economic efficient in the dairy cattle at Kharabo Farm.
In the present study, the susceptibility of four varities of wheat Maxipak 65,
M221×M24, Saberbek and Condoras in addition to the hybrid F4 (from the
hybridization of Maxipak-65 with M221×M24 for four successive generation)
against khapra beetle d
uring storage was estimated. The population growth of
the pest and percentage loss due to pest infestation were taken as criteria for
measuring resistance the against insect. The study indicate that the hybrid F4
was the best in productivity and early in production which are favorable
characters but contrarily it was highest susceptibility toward the insect
infestation. When the insect reared on the hybrid F4, appeared the highest
population density and at the same time the infestation caused in the highest
loss weight percentage. On the other hand the Maxipak-65 variety showed the
lowest population density of the pest and the lowest loss weight percentage due
to infestation than the other varieties and hybrid F4. This result indicates that
resistant character depressed during inbreeding during F4 hybrid production
in compared to parents therefore it must be early consumed to prevent the
infestation by the insect studied.
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