Muna M.M. Ahmed and Buthina M. Rahama

Institute of Environmental Studies, University of Khartoum
P.O.Box 123.

SUMMARY

21 Friesian heifers and 21 Friesian bull calves were randomly allocated to 3 rations (A, B, and C) formulated in such a way that sorghum gluten feed replaced cotton seed cake and sorghum grain alone or groundnut hulls respectively. Parameters measured were body weight, gain and dry matter consumption during 10 weeks experimental period.

Although the three rations were iso-caloric and iso-nitrogenous, the best performance was observed with ration C followed by B and A. Bull calves were heavier than the heifers, they consumed more food and had better feed conversion efficiency. Under Sudan conditions growth rate of exotic breeds could be improved through manipulation of voluntary feed intake.

INTRODUCTION

in preparing general recommendations for rearing of dairy exotic calves under tropical conditions like Sudan, it was possible to formulate different feeding strategies to see which would the best performance. Parameters such as growth rate and dry matter consumption were investigated.

Post weaning diet plays a critical role in calves development. The type of diet affects nutrient intake and live weight gain at puberty. The

negative weight gain during post weaning period tends to have an adverse influence on heifer reproduction and development (Granger et al. 1990). Heifers raised on a high plane of nutrition before and after puberty showed mammary impairment (Sejresen et al. 1982) due depressed level of circulating growth hormones that induce mammary development parenchyma development (Sejrsen et al. 1983). However, heifers reared moderately (0.76 kg/day) in the first year then more rapidly (1.18 kg/day) during pregnancy showed no mammary tissue development (Roger et al. 1983). In bull calves limiting nutrient intake during the prepubertal period decreased both testicular size (Van De Mark and Mayor, 1964) and circumference as well as lowered circulating testosterone (Pruitt et al. 1986).

Supplementation with concentrate was found to improve conception rate at first service (Gabber, 1987). Holstein heifers raised on concentrate and hay required 1.7 services for conception while their mates raised on conventional high roughage ration required 1.4 services (Gardener et al. 1971). Also high yielding cows were found to achieve better reproductive efficiency if adequately fed high energy and protein supply (Mcceary, 1991).

Relatively large differences in weight gain are observed among breeds and sexes as a reflection of differences in daily intake and feed conversion efficiency (Chewing et al. 1990). Istasse et al., (1990) reported average daily gain for Holstein-Friesian bulls of 1.36 kg vs 1.24 kg for Belgian Blue bulls, where the former (2.3 kg/100 body weight) consumed more food than the latter (1.8 kg/100 body weight). Differences between sexes showed higher live weight gain in males than females (Rollin and Guilbert 1954, Griffith, 1980).

Information pertaining to exotic breeds in Sudan is rare, hence this study was conducted to investigate the growth performance of Friesian calves fed conventional and agroindustrial byproducts under Sudan tropical conditions.

MATERIALS AND METHODS

Climate

The prevailing climatic conditions during the study were: mean

maximum temperature was 38.6 ± 1.1 C and mean minimum 25.7 ± 0.38 °C with mean relative humidity 50 ± 4.6% and mean solar radiation 23.4 ± 0.51 MJ/m² .

Animals and Feeds

21 heifers and 21 bull calves were used with body weight ranging from 60-110 kg and age between 2.5 and 4 months. Each group was subdivided into three sub-groups according age. The six sub-group were randomly allocated to three diets in a completely randomized design. Sorghum gluten feed was used to replace groundnut hulls, cotton seed cake and sorghum grain to formulate three rations as shown in Table 1. During the experimental period each subgroup of animals was kept separately in an open-side shed which was constructed with iron bars and partially roofed with sloped corrugated and galvanized zinc cover coated with an insulated material. The animal barn was oriented in a north-south direction, the floor was slightly sloping and made of concrete. Clean water was offered in metal troughs provided with special taps turned on when was pressed by the animal.

The experimental study covered two periods, an adaptation period of 16 days and a measurement period of 70 days. The tested ration (byproducts) was added gradually to the basal ration (25, 50, 75 and 100%) at 4 days interval.Green fodder (Sorghum vulgare) was offered ad-libitum.The animals were weighed at weekly interval forl 0 weeks. Daily food intake was measured by weighing the amounts of food offered and residues from the previous day. Feed conversion ratio was calculated by dividing gain in body weight by the amount of dry matter consumed. Chemical analysis of feed was determined according to AOAC (1970).

The data were analyzed using analysis of variance. (two-way) and differences between means were tested by least significant difference (LSD), Simple linear regression and correlation analysis were used to evaluate the effect of dry matter intake on body weight according to Steel and Tonic (1980).

RESULTS

When comparing the DMI of the three rations for heifer calves during the 10 weeks of the measurement period, ration C showed the highest intake (P < 0.05) followed by B and A except for week 4 (Table 2). For bull calves a similar trend was observed. However, no significant differences could be detected between rations A and B during weeks 1, 2, 3, 4, and 9 (Table 3).

Table 1. Ingredient and chemical composition of the experimental rations on dry matter basis.

Table 5. Reression of dry matter intake (Y) on body weight change (kg ^.75) (X) in female Friesian heifer calves.

Rations                                  Regression equation                            R²

A	Y = 39.82 — 6.26X	0.43	-0.68
B	Y = 16.6 + 5.69X	0.19	0.43
C	Y = -2.72 + 10.64X	0.82	0.92

Table 6. Regression of dry matter intake (Y) on body weight change (kg^°75) (X) in female Friesian bull calves.

Rations                                   Regression equation                             R²

A	Y = 32.07 + 0.57X	0.01	0.16
B	Y = 10.22 + 8.63X	0.48	0.71
C	Y = 14.89 + 5.66X	0.61	0.78

R² = Coefficient of determination; r = Coefficient of correlation. R > 0.12 is significant at P > 0.01.

For both heifers and bull calves a steady increase in body weight

gain was observed throughout the experimental period with ration C exhibiting highest gain followed by B and A .

The effect of sex on feed utilization was significant (P < 0.05) for dry matter consumption. Bull calves consumed significantly (P< 0.05) more food than heifers, they were heavier and showed better feed conversion efficiency (Table 4). Regression analysis of DMI on body weight of the three rations for heifers (Table 5) indicated a decline of 6.26 kg ^°.75 (P > 0.01) for every 1 kg increase in DMI of ration A. with ration B an increase in body weight (kg ^0.75) of 5.69 was obtained for 1 kg increase in DMI (P > 0.01). For ration C an increase of 10.64 kg ⁰⁷⁵ was obtained for every 1 kg increase in DMI. Male calves showed non-significant correlation with ration A. With rations B and C the correlations were significant (P > 0.01), the increase in body weights (kg ⁰⁷⁵) were 8.63 and 5.66 respectively for each increase in DMI.

DISCUSSION

Both sexes showed the best performance with ration C followed by B and A. This could be related to the highest proportion (30%) of cotton seed cake and sorghum grain (25%) in comparison with rations B and A (see Table 1). Cotton seed cake would have provided a source of by-pass protein, while sorghum grain provided a source of fermentable carbohydrate. This was found to be in agreement with other studies in cows (Campling et al. 1962) and bulls (Leng, 1984). Bypass proteins entering the small intestine are known to correct for the essential amino acids insufficiencies and provide ATP when oxidized, they were also observed to increase food intake, feed conversion efficiency and live weight gain (Nolan et al. 1986). Generally growing calves have high protein requirement and usually a source of bypass protein is required to achieVe maximum performance (Amos, 1986; Kloptenstein et al. 1991 and Coomer, 1993). With ration B, a source of fermentable carbohydrate (10% sorghum grain) might have assisted bacterial population in utilizing the available protein in the diet. However, ration A was devoid from both a source of fermentable carbohydrate or bypass protein which might have been reflected on the poor performance of this ration. Regression analysis had further confirmed this relationship between body weight changes in response to dry matter consumption of the three rations.

The average gain in body weights showed bull calves on ration B were similar to those obtained by Kesler (1962) for Friesian calves (0.58-0.81 kg/day) on pasture and barn feeding at different seasons. Also heifers fed diet B showed similar gain as that reported by Hollon and Mochrie (1961) for calves maintained on pasture.

With ration C, gain in body weight was comparable with that obtained by Haenlein et at (1962) for heifers fed non expanded grain (yellow corn + raw soybean) and those receiving diets varying in energy contents (0.6-1.0 kg/day) (Amos, 1986). The growth rate obtained for the heifers in this study with diet C (0.76 kg/day) is the optimum to sustain better mammary tissue development and subsequent increase in milk production (Swanson, 1960; Sejrsen et at , 1982 and Roger et al., 1983).

It could be concluded that, under the prevailing tropical conditions of Sudan the performance of exotic dairy breeds could be improved by designing more effective supplementation strategies to see the best influence during the critical prepubertal period. For heifer calves a daily gain of 0.76 kg was shown to be the best for mammary tissues development. For bull calves, 0.83 kg gain per day was ideal for the expression of full sexual behaviour at puberty.

REFERENCES

Amos, H.E. (1986). Influence of dietary protein degradability and energy concentration on growth of heifers and steers and intraruminal protein metabolism. J. Dairy Sci., 69 : 2099 — 2110.

AOAC (1970). Association of Official Agricultural Chemists. Oficial Methods of Analysis. Washington, DC. 5Opp.

Chewing, J.J.; Brown, A.H.; Johonson, Jr. Z.B. and Brown, C.J. (1990). Breed means for average daily gain, feed conversion and intake of beef bulls during post-rearing feed performance tests. J. Anim. Sci., 68: 1500 — 1504.

Campling, R.C., Freer, M. and Balch, C.C.(1962). Factors affecting the voluntary food intake by cows. 3. The effect of urea on voluntary intake of straw. Br. J. Nutr. 16: 15 — 124.

Coomer, J.C. (1993). Effects of supplemental protein source on ruminal fermentation protein degradation and amino acid absorption in steer and on growth and feed conversion efficiency in steer and heifers. J. Anim. Sci., 71: 3078 — 3086.

Gaber, S.S. (1987). Effect on concentrate addition to roughage in performance of dairy heifers. MSc Thesis, University of Khartoum.

Gardener, R.W., Schuch, J.D. and Vailes, L.G. (1971). Accelerated growth and early breeding in Holstein heifers. J. Dairy Sci., 60 — 194.

Granger, A.L.; Wyatt, W.E.; Hembry, F.G.; Graig, W.M. and Thompson, D.L. (1990). Effect of breed and wintering diet on heifer post-weaning growth and development. J. Anim. Sci., 68: 304 — 316.

Griffiths, T.W. (1980). The relative efficiency of food utilization of British Friesian entire male and castrate male at two levels of feeding. J. Anim. Sci., 30: 53 — 59.

Haenlein, G.F.W., Burton, D.W., Hoyt, H.G. and Mitchel, W.H. (1962). Effect of expanding or polluting upon feed digestibility and heifers growth. J. Dairy Sci., 54 : 754 — 758.

Hollon, B.F. and Mochrie, R.D. (1961). Pasture vs barn feeding for raising calves. J. Dairy Sci., 44 : 977.

Istasse, L., Van Eemaeme, C., Evrard, P.L., Gabriel, A., Baldwin, P., Maghuin, G. and Bienfait, J. (1990). Animal performance, plasma hormones and metabolites in Holstein and Belgian blue growing-fattening bulls. J. Anim. Sci., 68 : 2666 2673.

Kesler, E.M. (1962). Growth of Holstein calves on pasture from 6-20 weeks of age. J. Dairy Sci., 45 : 202 — 209.

Klopfenstein, T.J., Britton, R.A. and Stock, R.A. (1991). Feed technology and other methods for increasing the bypass protein for ruminants fed low quality forages. Isotopes and Related Techniques in Animal Production and Health. Vienna, IAEA pp. 71 — 81.

Leng, R.A. (1984). The potential of solidified molasses-based blocks for the correction of multinutritional deficiencies in buffaloes and other ruminants fed low-quality agro­industrial byproducts. Nuclear and Related techniques in Animal Production and Health, IAEA-Vienna. pp. 135 — 150.

Mcceary, I.O. (1991). The effect of milk production in reproductive performance in the high producing and BST

supplemented dairy cows. Bovine Practitioner No. 26, 68 — 72.

Nolan, J.V., Lee, G.J., Henessy, D.W. and Leng, R.A. (1986). Metabolic responses to supplementation in growing ruminants consuming low digestibility fibrous diets. Nuclear and Related techniques in Animal Production and Health, IAEA-Vienna. pp. 71 — 81.

Pruitt, R.J. Corah, L.H., Stevenson, J.S. and Kiracofe,C.H. (1986). Effect of intake and after weaning on the sexual development of beef bulls age at first mating, age at puberty, testesterone and scrotal circumference, J. Anim. Sci., 63 : 579 — 585.

Roger, D.H., Reynolds, I.P. and William, L. (1983). A quantitative Analysis of mammary glands of dairy heifers reared at different rate of lived weight gain . J. Dairy Res. 50 : 405 412.

Rollin, W.G. and Guilbert, H.R. (1954). Factors affecting growth of beef calves during the suckling period. J. Anim. Sci. 13: 517 — 527.

Sejrsen, E.K., Huber, J.T., Tucker, H.A. and Akers, R.M. (1982). Influence of nutrition on mammary development in prepubertal heifers. J. Dairy Sci. 65 : 793 — 800.

Sejrsen, E.K., Huber, J.T. and Tucker, H.A. (1983). Influence of Amount fed on hormone concentration and their relationship to mammary growth on heifers. J. Dairy Sci. 66 : 845 — 855.

Steel, R.G.D. and Torrie, J.H. (1980). Principles and procedures of Statistics (2^nd ed.) McGraw. Hill Books Co, New York.

Swanson, E.W. (1960). Effect of rapid growth with fattening of dairy Heifers on their lactating ability. J. Dairy. Sci. 43 : 377 — 387.

Van Denmark, N.L. and Manhger, R.E. (1964). Effect of energy intake on reproductive performance of dairy bulls growth, reproductive organs and puberty. J. Dairy Sci. 47 : 798 — 802.

Authors:

Muna Mahgoub Mohamed Ahmed Buthina Mustafa Rahama.

Download As : PDF