Dietary Vitamin or Mineral Mix Removal During the Finisher Period on Broiler Chicken Performance

Transcription

1 2002 Poultry Science Association, Inc. Dietary Vitamin or Mineral Mix Removal During the Finisher Period on Broiler Chicken Performance A. Maiorka, A. C. Laurentiz, E. Santin, L. F. Araújo, and M. Macari 1 Faculdade de Ciências Agrárias e Veterinárias Campus de Jaboticabal Unesp, Cep: Jaboticabal SP Brazil Phone: FAX: Primary Audience: Nutritionists, Researchers, Broiler Production Managers SUMMARY The effect of dietary vitamin (VS) and mineral (MS) mix withdrawal between 42 and 49 d of age on broiler chicken performance was evaluated. The diets were formulated based on corn and soybean meal, and the experiments were conducted in floor pens using wood shavings as litter. Trial 1 evaluated withdrawal of VS and MS mix at 42, 45, and 49 d. The results of this trial showed that VS and MS mix withdrawal at 42 d of age did not impair feed intake (FI) or weight gain (WG), but feed conversion (FC) was improved (P = 0.043) when both mixes were maintained in the diets until 49 d of age. Trial 2 assessed the withdrawal of VS or MS mix at 42 d of age. FI and WG were not affected by withdrawal, but FC was poorer (P = 0.035) for the broilers fed the diet without VS. The relative liver weight was reduced by VS or MS mix withdrawal (P = and P = 0.001, respectively). Carcass, breast, and leg yields were not affected by VS or MS mix withdrawals in either trial. The findings of the study suggested that VS mix withdrawal during the final period of broiler chicken growth was more deleterious than the withdrawal of MS mix, because it affected FC ratio. VS or MS withdrawal during this period did not affect carcass yield. Key words: broiler, mineral, vitamin, withdrawal feed 2002 J. Appl. Poult. Res. 11: DESCRIPTION OF PROBLEM Although dietary vitamin and mineral requirements for birds have been periodically reestablished [1, 2], some aspects of these requirements are continuously questioned. The requirements are normally determined in young birds by using highly purified diets and in thermoneutral conditions; however, the actual requirement can be quite different in poultry production systems, as the birds are subjected to stressful situations that can be avoided during experimental trials. Because the deficiency of minerals and vitamins requires long periods to demonstrate clinical signs [3], the withdrawal of vitamin or mineral supplements in grower diets has been evaluated in the last few years as a way to reduce the costs of broiler chicken production [4]. Several reports [4, 5, 6, 7] have shown the effect of vitamin or mineral withdrawal during the finisher period on the performance of broiler chickens. In studies using practical diets, a total lack of vitamins and min- 1 To whom correspondence should be addressed: macari@fcav.unesp.br.

2 122 JAPR: Research Report TABLE 1. Compositions of the diets used in starter and grower periods, Trials 1 and 2 Starter Grower Ingredient (1 21 d) (22 41 d) Yellow corn, % Soybean meal, % Soybean oil, % Dicalcium phosphate, % Limestone, % Salt (NaCl), % Vitamin and trace mineral mix A DL-Methionine, % Calculated analysis ME, kcal/kg 2,900 3,150 Crude protein, % Calcium, % P available, % Sodium, % Methionine, % Methionine + cystine, % Lysine, % A Provided per kilogram of diet: vitamin A (11,925 IU); vitamin D 3 (2,250 IU); vitamin E (9 IU); vitamin K 3 (1.8 mg); vitamin B 12 (0.02 mg); thiamin (1.1 mg); riboflavin (9 mg); pyrodoxine (1.8 mg); biotin (0.1 mg); pantothenic acid (9.9 mg); niacin (38.25 mg); folic acid (0.9 mg); choline (680 mg); iodine (1.2 mg); selenium (0.18 mg); iron (70 mg); copper (10 mg); zinc (60 mg); manganese (70 mg). erals in the diet is not at issue, as corn and soybean meal provide a portion of the requirements. Further, fat-soluble vitamins are stored in the fatty tissue of the body and can be remobilized when a deficiency occurs. Thus, the withdrawal of vitamin and mineral supplements during the last week of broiler chicken production may be a way to reduce costs for poultry producers. This study was carried out to evaluate the effects on broiler performance of withdrawing vitamin and mineral supplements at 42, 45, and 49 d of age. MATERIAL AND METHODS General Procedure Two trials were conducted to evaluate the withdrawal of vitamin (VS) and mineral (MS) supplements during the final phase of broiler chicken growth (between 42 and 49 d of age). Up to 41 d of age, birds were maintained in pens with wood shavings for litter and were fed diets based on corn and soybean meal (Table 1). Trial 1 assessed the effect of VS and MS withdrawal from 42, 45, or 49 (control) d of age, and Trial 2 evaluated the effect of VS or MS withdrawal from 42 d of age. The diets used during the experiment (42 to 49 d) were also formulated based on corn and soybean meal (Table 2). At the end of the experiment (49 d), birds were weighed, and then 10 birds from each treatment were selected at random, subjected to 6 h fasting, reweighed, and then slaughtered. Dressed carcasses, including giblets, were taken immediately after evisceration and used to determine carcass yield. Then breast, leg (drumstick and thigh), and liver weights were taken and used to calculate individual percentages of the dressed carcass weight. Trial 1 Four hundred fifty, 1-d-old, Cobb500, male chicks were used in this trial. Chicks were raised until 41 d of age, as described in the general procedure, weighed, and distributed into pens in a completely randomized design with three treatments (T1 = diet without VS and MS supplements from 42 to 49 d; T2 = diet without VS and MS supplements from 45 to 49 d; T3 = diet with VS and MS until 49 d) with five repetitions per treatment of 30 birds each [8]. At 42 and 49 d of age, birds and feed were weighed to determine feed intake (FI),

3 MAIORKA ET AL.: VITAMIN MINERAL NUTRITION 123 TABLE 2. Compositions of the diets used during the experimental period (42 through 49 d of age) in Trials 1 and 2 A Trial 1 Trial 2 With VS Without VS With VS Without VS With VS Without VS Ingredient and MS and MS and MS and with MS and without MS and MS Yellow corn, % Soybean meal, % Soybean oil, % Dicalcium phosphate, % Limestone, % Salt (NaCl), % DL-Methionine Vitamin mix B Trace mineral mix C Sand, % Calculated analysis ME, kcal/kg 3,250 Crude protein, % Calcium, % 0.80 P available, % 0.33 Sodium, % 0.14 Methionine, % 0.32 Methionine + cystine, % 0.63 Lysine, % 0.85 A VS = vitamin mix supplement; MS = mineral mix supplement. B Provided per kilogram of diet: vitamin A (11,925 IU); vitamin D 3 (2,250 IU); vitamin E (9 IU); vitamin K 3 (1.8 mg); vitamin B 12 (0.02 mg); thiamin (1.1 mg); riboflavin (9 mg); pyridoxine (1.8 mg); biotin (0.1 mg); pantothenic acid (9.9 mg); niacin (38.25 mg); folic acid (0.9 mg); choline (680 mg). C Provided per kilogram of diet: iodine (1.2 mg); selenium (0.18 mg); iron (70 mg); copper (10 mg); zinc (60 mg); manganese (70 mg). weight gain (WG), and feed conversion ratio (FC). Trial 2 Six hundred, 1-d-old, Cobb500, male chicks were raised until 41 d of age, fed according to the management procedure described in the general procedure, and distributed into pens in a completely randomized de- sign with four treatments forming a2(with and without VS) 2 (with and without MS) factorial design, with five repetitions of 30 birds each [8]. The treatments were as follows: T1 = diet with VS and MS from 42 to 49 d of age; T2 = diet without VS, but with MS from 42 to 49 d; T3 = diet with VS, but without MS from42to49d;t4= diet without VS or MS from 42 to 49 d. At 42 and 49 d, the birds TABLE 3. Feed intake (g), body weight gain (g), and feed conversion ratio (g/g) of broiler chickens from 42 to 49 d of age when supplemented vitamin (VS) and mineral (MS) mixes were withdrawn; Trial 1 Age (d) at removal Feed intake Body weight gain Feed conversion of VS and MS (g) (g) (g/g) 42 (T1) 1, a 45 (T2) 1, ab 49 (T3) 1, b P-value CV A (%) a,b Means in a column without common superscripts differ significantly (P < 0.05). A CV = coefficient of variation.

4 124 JAPR: Research Report TABLE 4. Carcass, breast, leg, and liver yields at 49 d of age when supplemental vitamin (VS) and mineral (MS) mixes were withdrawn; Trial 1 Age (d) at removal Carcass Breast Leg Liver of VS and MS (%) (%) (%) (%) ] P-value CV A (%) A CV = coefficient of variation. and feed were weighed to determine FI, WG, and FC. RESULTS AND DISCUSSION The results from Trial 1 for FI, WG, and FC are shown in Table 3. VS and MS mixes withdrawn at different ages did not significantly affect FI (P = 0.370) or WG (P = 0.296). However, despite the lack of a statistical difference, the data show a tendency for better weight gain of broiler chickens fed supplemented (VS and MS) diets until the end of the experimental. FC was significantly influenced by the age at which the dietary supplement was withdrawn, with birds on T3 having a FC of as compared to for the broilers on T1 (P = 0.043). FC for T2 (withdrawal at 45 d) was intermediate and not significantly different from T1 or T3. Carcass, breast, and leg yields and liver weight of the broilers in Trial 1 (Table 4) were not affected by VS and MS withdrawals (P = 0.634, P = 0.814, P = 0.908, and P = 0.376, respectively). Withdrawal of VS or MS mix from the diets of broiler chickens at 42 d of age in Trial 2 did not significantly affect FI or WG, despite a difference of 54 g between the means for WG of birds receiving or not receiving vitamins (Table 5). Feed conversion was affected by VS withdrawal (P = 0.035); broilers fed a diet without VS had poorer FC as compared to those receiving the vitamin mix. Although vitamins are not an energetic nutrient, they act as cofactors in several metabolic reactions, thus increasing the efficiency of the synthesis pathways in the animal. Because TABLE 5. Feed intake (g), body weight gain (g), and feed conversion (g/g) of broiler chickens from 42 to 49 d of age with or without mineral and vitamin supplementation, Trial 2 Feed intake Body weight gain Feed conversion Treatment A Minerals Vitamins (g) (g) (g/g) T1 (+) (+) 1, T2 (+) ( ) 1, T3 ( ) (+) 1, T4 ( ) ( ) 1, CV B (%) Principal effects Minerals ( ) 1, Minerals (+) 1, Vitamins ( ) 1, Vitamins (+) 1, Probability Minerals (M) Vitamins (V) M V A T1 = diet with supplemental vitamin (VS) and mineral (MS) mixes from 42 to 49 d of age; T2 = diet without VS but with MS from 42 to 49 d; T3 = diet with VS but without MS from 42 to 49 d; T4 = diet withut VS or MS from 42 to 49 d. B CV = coefficient of variation.

5 MAIORKA ET AL.: VITAMIN MINERAL NUTRITION 125 TABLE 6. Carcass, breast, leg, and liver yields of broilers at 49 d of age with or without mineral and vitamin supplementations; Trial 2 Carcass Breast Leg Liver Minerals Vitamins (%) (%) (%) (%) T1 (+) (+) T2 (+) ( ) T3 ( ) (+) T4 ( ) ( ) CV A (%) Principal effects Minerals ( ) Minerals (+) Vitamins ( ) Vitamins (+) Probability Minerals (M) Vitamins (V) M V A CV = coefficient of variation. broilers have a heightened demand for vitamins during periods of growth, the reduction of these nutrients during the finisher period would be expected to increase feed conversion. MS withdrawal from the diet at 42 d of age did not significantly influence (P = 0.324) feed conversion ratio (Table 5). Yields of broiler carcass, breast, and leg were not affected by VS or MS mix withdrawal from the diet at 42 d of age. However, relative liver weight was reduced when VS or MS mix occurred (P = and P = 0.001, respectively). The findings of this study differ slightly from those reported by Skinner et al. [4], as they showed that VS and MS mix withdrawal from the finisher diet of broiler chickens did not affect performance. We found an increase in FC after VS withdrawal; however, carcass traits were not affected in either study. Skinner et al. [4] suggested that the lack of a withdrawal effect could be related to the availability in the body of vitamins and minerals for further growth, as the amount of these supplements usually exceeds two or three times the recommended broiler chicken requirement in poultry diets. In Trial 2 of this study, the lack of vitamin or mineral supplements in the diets reduced the percentage liver weight, suggesting that liver metabolism might also have been affected by the withdrawal of these supplements (Table 6). Deyhim and Teeter [6] also demonstrated that broiler chickens reared in batteries under a cycling ambient temperature (24 to 35 C, creating heat stress), and fed diets without VS and MS had reduced weight gain, higher mortality and poorer feed conversion as compared to birds fed normally supplemented diets. However, in this study, only an elevation in FC was noted when vitamin supplementation was withdrawn from 42 to 49 d. CONCLUSIONS AND APPLICATIONS 1. The findings of the study suggest that withdrawal of vitamin mix during the final period of broiler chicken growth is more deleterious than withdrawal of mineral mix, because its affect on FC. 2. Carcass yield was not affected by withdrawal of vitamin or mineral mix.

6 126 JAPR: Research Report REFERENCES AND NOTES 1. National Research Council Nutrient Requirements of Domestic Animals. Nutrient Requirements of Poultry. 8th rev. ed. Natl. Acad. Sci., Washington, DC. 2. National Research Council Nutrient Requirements of Domestic Animals. Nutrient Requirements of Poultry. 9th rev. ed. Natl. Acad. Sci., Washington, DC. 3. Lesson, S., and J. D. Summers Commercial Poultry Nutrition. 2nd ed. University Books, Guelph, ON, Canada. 4. Skinner, J. T., A. L. Waldroup, and P. W. Waldroup Effects of removal vitamin and trace mineral supplements from grower and finisher diets on live performance and carcass composition of broilers. J. Appl. Poult. Res. 1: Summers, J. D., S. Lesson, and A. E. Ferguson Performance and leg conditions of caged and floor reared broilers fed diets deficient in selected vitamins and minerals. Poult. Sci. 57: Deyhim, F., and R. G. Teeter Dietary vitamin and/ or trace mineral premix effects on performance, humoral mediated immunity, and carcass composition of broilers during thermoneutral and high ambient temperature distress. J. Appl. Poult. Res. 2: Rutz, F., E. G. Xavier, and G. M. Dadalt Exigências nutricionais para a fase final (energia, aminoácidos, vitaminas, minerais e aditivos). Pages in Anais Conferência Apinco de Ciência e Tecnologia Avícola, Campinas, SP, Brasil. 8. Data were analyzed by analysis of variance. When differences were significant, means were verified using Tukey s test. Significance implies P < Acknowledgment The authors thank Fundação de Amparo à Pesquisa de Estado de São Paulo for financial support.