| Livestock Research for Rural Development 10 (2) 1998 | Citation of this paper |
An experiment was carried out to determine the effectiveness of vitamin C supplementation on health and the contents of Ca and P in the tibia bone of the chick. Chicks from 0-4 weeks of age were allocated into two groups, each consisting of 560 heads. The control group was fed on a basal diet supplemented with a preparation of vitamins A, D, and E; the experimental group was fed on the same basal diet supplemented with vitamins A, D, and E, plus vitamin C at a dose of 150 ppm. The housing, management, nutritional and sanitary conditions were the same for the two groups. It was found that the supplementation with vitamin C did not significantly affect the growth rate, but reduced the mortality and incidence of food abnormality, increased the contents of Ca and P in the tibia bone of 21 day old chicks.
Calcium (Ca) and phosphorus (P) play a very important role in mineral nutrition of poultry. Among many factors affecting Ca and P metabolism vitamin D3 is of most importance. It is absorbed from ingested feed in the intestines into the circulation. In the liver, it is converted into 25 hydroxide canciferol (25(OH)D3), and then in the kidney, into 1,25 dihydroxide canciferol (1,25(OH)2D3) which has an ability to enhance Ca and P absorption through the intestinal wal and small renal tubes and facilitate the transfer of Ca into the bone. Apparently, vitamin D3 is of crucial significance in Ca absorption and metabolism. Involved in vitamin D3 metabolism is enzyme 25-hydroxide-D3-hydroxylase, which is activated by vitamin C.
In addition, it has been known that in the period from 0 to 2 weeks of age, vitamin C is not yet synthesized in the body of the chick. Therefore, dietary vitamin C deficiency should adversely affect Ca and P metabolism.
To study the effect of vitamin C supplementation of diets for 0-4 week old chicks an experiment was carried out to determine the effectiveness of vitamin C supplementation on health and the contents of Ca and P in the tibia bone of the chick.
Chicks from 0-4 weeks of age were allocated into two groups, experimental and control, each consisting of 560 heads. The control group was fed on a basal diet supplemented with a preparation of vitamins A, D, and E; the experimental group was fed on the same basal diet supplemented with vitamins A, D, and E, plus vitamin C at a dose of 150 ppm. The housing, management, nutritional and sanitary conditions were the same for the two groups.
From each group, 140 chicks were randomly chosen for slaughtering to study the body weight at 7, 14, 21 and 28 days of age. The results are presented in Table 1.
| Table 1 : Body weight of chicks from 0 to 4 weeks of age (g) | ||||
| Weeks of age | Control group | Experimental group | ||
| Mean ± SE | CV (%) | Mean ± SE | CV(%) | |
| 1 | 118.3 ± 1.28 | 13.20 | 118.9 ± 1.25 | 12.3 |
| 2 | 250.4 ± 2.42 | 11.80 | 254.6 ± 2.38 | 11.9 |
| 3 | 483.0 ± 5.30 | 13.35 | 486.4 ± 5.60 | 14.0 |
| 4 | 529.2 ± 5.90 | 13.60 | 537.6 ± 6.93 | 12.0 |
As can be seen in Table 1, the body weights in both groups increased in a parallel way over the weeks of age. Compared with the control, the average weights of the experimental chicks were higher from week 2 to week 4; however, the differences were not statistically significant.
Another point that should be noted in this experiment is that vitamin C supplementation resulted in much better appearance, the chicks having a polish feather coat.
Deaths of chicks were recorded every week. The results are shown in Table 2.
| Table 2 : Mortality of chicks during experiment | ||||
| Weeks of age | Control group | Experimental group | ||
| dead chicks (heads) | mortality, (% ) | dead chicks (heads) | mortality, (% ) | |
| 1 | 7 | 1.42 | 3 | 0.53 |
| 2 | 12 | 2.17 | 6 | 1.07 |
| 3 | 2 | 0.37 | 1 | 0.18 |
| 4 | 2 | 0.37 | 0 | 0.00 |
| Total | 23 | 4.1 | 10 | 1.78 |
Table 2 shows that the mortality of the control group over the 4 weeks of the experiment was higher than for the experimental. It is clear that the death rate was highest in the first 2 weeks and reduced afterward. The death rate of the control group was always 2-3 times higher for each week and 2.3 times higher for the whole period compared with the experimental group. The differences were statistically significant (P<0.01).
All the chicks were checked for foot abnormality and the results are given in Table 3. It can be pointed out from this table that the number of abnormal-footed chicks was higher in the control group than in the experimental group. Statistical analysis showed that the difference between the two groups was significant (P<0.01).
| Table 3: Abnormal-footed chicks during 4 weeks of experiment | ||||
| Weeks of age | Control group | Experimental group | ||
| abnormal-footed chicks | rate (%) | Abnormal-footed chicks | rate (%) | |
| 1 | 2 | 0.35 | 0 | 0.00 |
| 2 | 12 | 2.15 | 6 | 1.07 |
| 3 | 10 | 1.83 | 0 | 0.00 |
| 4 | 11 | 2.05 | 6 | 1.08 |
| Total | 35 | 6.25 | 12 | 2.14 |
The contents of Ca and P in the tibia bone were analyzed when the chicks were 21 days old. The results are shown in Table 4.
| Table 4: Ca and P contents in the tibia bone of 21 day old chicks | ||
| Experimental group | Control group | |
| Ca (%) | 1.42 ± 0.006 | 1.23 ± 0.007 |
| P (%) | 0.98 ± 0.008 | 0.73 ± 0.007 |
The contents of Ca and P in the tibia bone of the experimental group were significantly higher (P<0.05). That should have resulted in improved bone quality and reduced osporosis and rickets. The results help explain the lower rate of abnormal footed chicks in the experimental group as in Table 3. The findings were also in agreement with those of Franchini et al. (1993).
It can be concluded from the experiment that supplementation of the chick diet with vitamin C at a dose of 150 ppm:
Bains B S 1992 Nutritional approaches to minimize inadequate mineralisation. Proceedings of poultry science symposium held at the University of Queensland Gatton College. Australia.
Franchini A, A Meluzzi, G Manfreda and C Tosurelli 1993 Effects of vitamin C on broiler skeleton development. Atti-dell' Associazione Scientifica de Produzione Animale Vol 10: 451-524. Italy