Mahassin A. Mohamed1 and S.A. Mohamed2
1Shukaba Animal Resources Research Station, Wad Medani South, Sudan.
2 Department of Animal Science, Faculty of Agricultural Sciences, University of Gezira, Sudan.
Summary
198 Kenana calves (114 males and 84 females) in Barakat area of the Gezira Scheme were involved in this study during (1990/1992). an overall mean calf birth weight of 24.60±0.30kg during 283.72±0.21 days of gestation.
Sex of calf highly affected both gestation length and calf birth weight (P<0.001) male calves gestated 2-days longer and about 1kg heavier at birth than females.
A significant season influences on gestation length and calf birth weight the longest gestation (P<0.001) and heaviest weight (P<0.05) by the wet summer calvers in contrast to the shortest length of gestation and lightest weight attained by the dry summer ones.
Sex of calf and calving season of this study affects both gestation length and calf birth weight, male calves and wet summer longer and have heaviest weight
Introduction
Gestation length is among the most important traits in cow-calf operations. In domestic cattle the trait is known to be influenced by several genetic and non-genetic factors season of calving (Messine et al., 2007), breed and sex of calf (Reynolds et al., 1990). Birth weight is an important trait not only for breeding purposes, but also the revenue from sale proceeds of animal industry usually depends on animal’s weight particularly when they are reared for meat, dairy industry birth weight of dairy heifers is an important indication of their future performance (Isa et al., 2013).Birth weight is highly dependent on nutrition and is also influenced by genotype, parity, sex and season of calving (Kertz et al., 1997 and Isa et al., 2013).
The present study was initiated with the objective of determining the influence of sex and season of calving on gestation length and calf birth weight of Kenana calves in the Gezira State.
Materials and Methods
Animals:
198 multi-parious Kenana cows randomly derived from eight cattle herds located in four villages in Barakat area of the Gezira Scheme, longitude 33º 20E and latitude 14º 20N. the animals were of approximately similar body weight and age (between the second and the third parity). The study was conducted in the period from 1990-1992.
Housing:
Cows were penned into traditional earth-bedded unshaded yards fenced with Acacia shrubs.
Management:
Feeding practices in the Gezira depends on grazing natural pastures of mostly annual grasses during the rainy season. They also deponds on crops residues during summer and some green forages during winter season. Concentrate supplementation was also practiced by some farmers before or during milking time. Cows were traditionally milked with their calves present once per day and mated naturally with bulls permanently resided within the herds with no special milking yard.
Calf birth weight was taken immediately in the first 24 hours using a spring scale (Maximum capacity load of 150kg). Seasons were classified in to dry-summer (March-June), wet-summer (July-October) and winter (November-February).
Statistical analysis:
The data were analyzed using the Statistical Package for Social Sciences (SPSS) Mc Graw Hill1983. The least squares fixed model was fitted.
Yijk = U + Xi + Sj + Eijk
Where
Yij = The trait in question, gestation length or birth weight.
U = The overall mean underlying the trait.
Xi = The effect of sex (1= male; 2= female).
Sj = The effect of season (1= wet summer; 2= dry summer; 3= winter
season).
Eij = The error.
Results and Discussion
Table1. presents the overall mean of gestation length and calf birth weight of 198 Kenana calves (283.72±0.21 days and 24.60±0.30kg, respectively. The effect of sex was highly significant in both traits table 2. (P<0.001) Male calves gestation was 2-days longer and 1kg heavier at birth compared to their females counterparts (25.05±0.39 vs. 24.14±0.46) as shown in table 1.
Table 1. Effect of sex and season of calving on gestation length and
calf birth weight of Kenana cattle
| Factor | N | Gestation length (days) | Birth weight (kg) | ||
| LSM | SE | LSM | SE | ||
| Overall | 198 | 283.72 | 0.21 | 24.60 | 0.30 |
| Sex | |||||
| Male | 114 | 284.59a | 0.72 | 25.05a | 0.39 |
| Female | 84 | 282.48b | 0.32 | 24.14b | 0.46 |
| Season | |||||
| Dry summer | 51 | 280.77c | 0.31 | 23.66c | 0.45 |
| Wet summer | 86 | 286.61a | 0.41 | 25.41a | 0.58 |
| Winter season | 61 | 283.77b | 0.37 | 24.72a | 0.53 |
LSM = Least squares means.
SE = Standard errors
Means with different superscripts differs significantly.
Season of calving, tables (1, 2) exerted a significant effect on gestation length and calf birth weight. A significantly (p<0.001) longer gestation (286.61±0.40 days) and significantly heavier birth weights (25.41±0.58 kg) were displayed by wet summer calves. The gestation length of the dry summer calves was shorter (280.77±0.31 days) and the birth weight of calves was lighter (23.66±0,45kg).
Table 2. Analysis of variance of gestation length and birth weight of
Kenana cattle by sex and season of calving
| Source | DF | Gestation length | Birth weigh | ||||
| MS | F | P | MS | F | P | ||
| Sex | 1 | 293.620 | 35.034 | 0.000 | 39.831 | 2.297 | 0. 13 |
| Season | 2 | 448.074 | 66.587 | 0.000 | 52.036 | 3.001 | |
| Error | 194 | 8.381 | – | – | 17.341 | – | 0.50 |
Differences in gestation length have been reported among cattle breeds. Most previous evidence suggested longer days in gestation for European breeds (Reynold et al., 1990). Alim (1960) estimated a gestation length of 283.0 days in a herd of Kenana cattle. This is close to the results of the present study. however, Osman (1972) in a study on Baggara cattle found a higher estimate of 287.2 days.
In agreement with the results obtained by Saeed, et al., (1987) sex of calf in this study showed a definite influence (P<0.001) on gestation length which was 2-days longer for male carrying calves. Similar results ( Norman et al., 2009 and Jainudeen and Hafez, 2000) were attributed this trend to the different endocrine functions of male and female fetuses which interact differently with endocrine control of the parturition. They indicated that as gestation length increases, birth weight also increases from 0.3 to 0.8 pounds per day.
The current gestation length was highly affected by calving season (P<0.001) with the shortest length obtained by in the dry summer table 2.
The studied village Kenana herds secured an average birth weight lower than their counterparties at Um Banein Station (Saeed et al., 1987) and Nisheshiba Research Station (Khalafalla, 1977). Compared to Asiatic breeds Kenana seems to deliver heavier weights than the local Iraqi (21.25 to 22.34kg) and Sahiwal (21.6kg) as reported by (Said, 1978 and Khan et al., 1999) respectively.
The effect of sex on birth weight in this study was in favour of male calves. This is similar to the findings of study on Holstein, Friesian x Kenana and Butana crossbred calves ( Kertz et al., 1997 and Abd ElAziz et al., 1991) respectively. They found heaviest weights for bull calves and stated that birth weight was highly affected by breed and sex of calf.
Calving season in this study was a significant factor affecting birth weight. The dry summer calves exhibited a significant reduction in birth weight (P<0.05). Mustafa et al. (2003) claimed similar findings in Red Sindhi cattle. There was a tendency in their data for lower weights during April/June. Apori and Hagan (2014) indicated that elevated temperatures resulted in directing a greater proportion of blood flow towards the extremities to keep cool, there by decreased nutrients flow to the fetus resulting in a decreased birth weight. The present results are at variance with the findings reviewed by Osman (1972); Kocak et al. (2007) and Akdag et al. (2011). These might be attributed to different breeds at various managerial and ecological conditions and the usage of various statistical methods in evaluating the data.
Conclusion
Gestation length and birth weight were influenced by sex and season of calving that male calves gestation was longer and resulted in heavier birth weights than females. The wet summer season was the most desirable season of birth that resulted in a heavier birth weights.
Acknowledgments
I am indebted to the herd owners for provided data.
References
Abdel Aziz, B.E.; Ali, T.E. and Ahmed, F.A. (1991). Some genetic and
environmental factors affecting birth weight of Butana subtype and Friesian x Kenana crosses at Atbara and Nisheashiba Research centers. Sudan J. Anim. Prod. 4 (2): 75.
Akdag, F.; Arslan, S.; Caynak, A. and Teke, B. (2011). The relationships
of phenotype, genotype and some environmental factors with birth weight in Jersey calves. African Journal of Biotechnology 10 (37): 7308.
Alim, K.A. (1960). Reproductive rates and milk yield of Kenana cattle in
Sudan J. Agric. Sci., (Camb.), 55: 183.
Apori, S.O. and Hagan, J.K. (2014). The effect of non-genetic factors on the
reproductive performance of Sanga and Friesian x Sanga crossbred dairy cattle breeds kept under hot and humid environment. Tropical Animal Health and production. 46 (6): 1045.
Isa, Y.; Eyduran, E. and Kaygisiz, A. (2013). Determination of non-genetic
factors influences birth weight using regression tree method in Brown
Swiss cattle. Canadian Journal of Applied Sciences 1 (3): 382.
Jainudeen, M.R. and Hafez, E.S.E. (2000). Gestation prenatal physiology
and parturition, In: Hafez, E.S.E.; Hafez, B., (Eds). Reproduction in farm animals. Lippincott, Williams and Wilkins, Boston, Pp. 140.
Kertz, A.F.; Reutzel, L.F.; Barton, B.A. and Ely, R.L. (1997). Body
weight, body condition score and wither height of peripartum Holstein cows and body weight and sex of calves by parity. J. Dairy Sci., 80: 525.
Khalafalla, A.M. (1977). The reproductive performance of a herd of Kenana
Cattle (Northern Sudan Zebu) M. V. Sc., thesis, University of Khartoum, Sudan.
Khan, U.N.; Dahlin, A.; Zafar, A.H.; Saleem, M.; Chaudhry, M.A. and
Philipson, J. (1999). Sahiwal cattle in Pakistan: Genetic and environmental causes of variation in body weight and reproduction and their relationship to milk production. J. Anim. Sci., 68 (1): 97.
Kocak, S.; Tekerli, M.; Ozbeyaz, C. and Yuccer, B. (2007). Environmental
and genetic effects on birth weight and survival rate in Holstein calves. Turk. J. Vet. Anim. Sci., 31 (4): 241.
McGraw Hill (1983). Statistical Package for the Social Sciences User’s
Guide, New York, U.S.A. Pp. 988.
Messine, O.; Schwalbach, I.J.M.; Mbah, D.A. and Ebangi, A.L. (2007).
Non-genetic factors affecting gestation length and post-partum intervals in Gudali zebu cattle of Adamawa Highlands of Cameron Tropical tural, 25 (3): 129.
Mustafa, M.I.; Latif, M.; Bashir, M.K. and Ahmed, S. (2003).
Reproductive performance of Red Sindhi cattle under hot and humid environment of Balochistan Province of Pakistan. Pakistan Veterinary Journal 23 (2): 66.
Norman, H.D.; Wright, J.R.; Kuhn, M.T.; Hubbard, S.M.; Cole, J.B. and Van Raden, P.M. (2009). Genetic and environmental factors that affect gestation length in dairy cattle. J. Dairy Sci., 92: 2259.
Osman, A.H. (1972). Environmental factors influencing reproductive rates
and milk production under range condition. Trop. Agric. (Trinidad) 51: 549.
Reynolds, W.L.; Urick, J.J. and Knapp, B.W. (1990). Biological type
effects on gestation length, calving traits and calf growth rate. J. Anim. Sci., 68: 630.
Saeed, A.M.; Ward, P.N.; Light, D.; Durkin, J.W. and Wilson, R.T.
(1987). Characterization of Kenana cattle at Um Banein, Sudan, ILCA Res. Rept. N. 16, Addis Ababa, Ethiopia.
Said, S.I. (1978). Some environmental and genetic factors affecting birth and
weaning weight of Friesian, Jenubi and their crosses. M. Sc. thesis, University of Bagdad, Iraq.
Authors :
Mahassin Abdel Razig Mohamed
Salah Abdalla Mohamed
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