A study on the effects of diets containing varying levels of cocoa pod husk (CPH) and 5% NaOH-treated corn cob on the growth and reproductive performance of confined djallonke sheep

Five experiments were conducted to evaluate the effect of diets containing various proportions of cocoa pod husk (CPH) and 5%. NaOH-treated corn cob on the growth rate and reproductive performance of confined Djallonke sheep. Five diets designated as 1, 2, 3, 4 and 5 were formulated to contain 0, 150, 300, 450 and 600 g/kg DM cocoa pod husk respectively. The diets also contained 5%. NaOH-treated corn cob (0, 150, 300, 450 and 600 g/kg DM) in an increasing proportion as the level of cocoa pod husk in the diets decreased. Other ingredients included in the diets were wheatbran, cottonseed cake, dicalcium phosphate, sodium chloride and trace mineral-vitamin premix. The diets were formulated to be isonitrogenous (about 2%. nitrogen or 13% CP). In the first experiment (growth rate studies), 50 young females (gimmers) of the Djallonke breed of sheep ranging in body weight from 5 to 13 kg were individually fed and watered ad libitum for 150 days and dry matter intake, water intake, daily bodyweight gain and feed conversion efficiency were determined. In the second experiment (metabolism studies), five young weaned Djallonke ram lambs weighing 5 to 11 kg were fed on each of the five diets in a latin-square design. Dry matter and organic matter intake, apparent digesbility coefficients of dry matter, organic matter and crude protein and digestible dry matter and digestible organic matter intake were measured. The third experiment (rumen pH and ammonia studies) involved feeding the same diets used in the growth rate a:d metabolism studies to five fistulated adult wethers (Djallonke x Sahel) in a latin-square design and measuring rumen pH and ammonia levels from 1 to 12 h and also 24 h after feeding. In the fourth experiment (reproductive studies), animals used in the growth rate studies belonging to the same dietary treatment (10 animals per treatment) were grouped and a ram was then introduced into each of the five groups for breeding. The parameters studied include weight at puberty, weight c first normal oestrous cycle, weight at first mating, conception rate, gestation length, weight at first lambing, prolificacy and birth weight of lambs. The animals were also bled through jugular venipuncture once every 7 days during both the individual and group feeding periods and plasma stored at - 20°c until assayed for progesterone. In addition, ten out of the fifty gimmers were bled daily for 53 consecutive days during the individual feeding period and progesterone from blood plasma was used to study the pattern of the oestrous cycle. The fifth experiment (haematological and blood biochemical studies), involved taking blood samples from the jugular vein of the sheep during both the individual and group feeding periods at 4-weekly intervals (day 28, 56, 84, 112 and 140) for the determination of blood metabolites and constituents; glucose, packed cell volume, haemoglobin, total protein, albumin, globulin, glutamic oxaloacetic transaminase (GOT), alkaline phosphatase, calcium, inorganic phosphorus, sodium and potassium. In the growth rate studies, dietary treatment significantly (P<0.0l) affected mean daily dry matter intake per unit of metabolic body size. The mean daily dry matter intake increased with increasing proportion of cocoa pod husk in the diets. The corresponding values for diets 1, 2, 3, 4 and 5 were 73.4, 86.4, 95.4, 101.3 and 99.0 g respectively. Mean daily water intake per unit of metabolic body size was not significantly (P>0.05) influenced by dietary treatment. Mean daily water intake ranged from 326.2 to 359.7 ml. Growth rates and feed conversion efficiencies were not significantly (P>0.05) influenced by the level of inclusion of cocoa pod husk in the diets. Growth rates values ranged from 37 to 35 g/day while values for feed conversion efficiency ranged from 12 to 18 kg feed/kg gain in bodyweight. In the metabolism studies, the mean daily dry matter and organic matter intake per unit of metabolic body size were significantly (P<0.05) influenced by dietary treatments. The values increased with increasing level of cocoa pod husk in the diets. The mean daily dry matter intake of sheep fed diets 1, 2, 3, 4 and 5 were 80.6, 83.4, 95.0, 105.8 and 103.6 g respectively while the mean daily organic matter intake values were 71.8, 74.4, 85.0, 95.2 and 95.4 g for sheep fed diets 1, 2, 3, 4 and 5 respectively. Apparent digestibility coefficients of dry matter and organic matter were significantly (P<0.Ol) affected by dietary treatments. The values decreased as the proportion of cocoa pod husk in the diets increased. Apparent digestibility coefficient of dry matter values were 59.02, 51.80, 49.37, 46.71, and 44.67%, while the values for apparent digestibility coefficient of organic matter were 59.26, 51.36, 48.59, 45.39 and 43.62% for diets 1, 2, 3, 4 and 5 respectively in both cases. Similarly, apparent digestibility coefficient of crude protein was significantly (P<0.Ol) affected by dietary treatment. The values decreased as the level of cocoa pod husk in the diets increased. The values recorded for diets 1, 2, 3, 4 and S were 63.38, 54.78, 53.23, 51.29 and 47.71% respectively. Mean daily digestible dry matter intake and mean daily digestible organic matter intake per unit of metabolic body size were however, not significantly (P>0.05) affected by dietary treatments. The mean daily digestible dry matter intake values ranged from 43 to Sag while the values for mean daily digestible organic matter intake ranged from 38 to 43 g. Rumen pH and ammonia levels were not significantly (P>0.05) influenced by dietary treatments. The rumen p1-I values ranged from 6.0 to 6.7 while rumen ammonia levels ranged from 129.6 to 159.8 mg/1000 ml In the reproductive studies, dietary treatment did not significantly (P>0.05) affect the weight at which gimmers attained puberty, weight of the gimmers at first normal oestrous cycle and weight at first mating. Puberty was attained at a mean weight of 12.5 ± 0.24kg, about 55.6% of the bodyweight at the time of first lambing. The weight of the gimmers at first normal oestrous cycle averaged 15.6 ± 0.44 kg, while the overall mean weight at first mating was 16.5 ± 0.41 kg. All the gimmers conceived at first service. Gestation length, weight at first lambing and prolificacy were also not significantly (P>0.05) influenced by the level of cocoa pod husk in the diets. Gestation length averaged 152 ± 0.74 days, weight of gimmers at first lambing averaged 22.5 ± 0.45 kg, while prolificacy averaged 102 ± 1.79%. Sex of lambs of the primiparous ewes did not have any significant (P>0.05) effect on gestation length. Gestation length of the primiparous ewes lambing males and females were 151.6 and 152.4 days respectively. Birth weight of the lambs was however, significantly (P<0.05) affected by dietary treatment. The values for lambs of primiparous ewes fed diets 1, 2, 3, 4, and 5 were 1.5, 1.6, 1.8, 1.6 and 2.1 kg respectively. The overall mean birth weight was 1.7 ± 0.24 kg. Sex had no significant (P>0.05) influence on birth weight of lambs. Both males and females had mean birth weight of 1.7 kg. Oestrous cycle length averaged 17.2 ± 0.44 days (15 to 20 days) . Progesterone levels were low at oestrus, the average value being 0.8 ± 0.17nmol/1. Peak progesterone level of 8.0 ± 0.84nmol/l was attained on day 14 of oestrous cycle. Trends in progesterone levels for the fifty gimmers on the five dietary treatments during gestation were similar. Peak progesterone levels were attained around days 112 and 119 (18.2 to 23.3 nmol/l) followed by a sharp decline at the time of lambing (day 149.4 to 153.9; 0.8 to 2.9 nmol/l) In the haematological and blood biochemical studies, dietary treatment significantly (P<0.01) affected sodium and potassium levels in the blood of the non-pregnant and pregnant animals. Sodium levels decreased, while potassium levels increased with increasing levels of cocoa pod husk in the diets. The levels of other blood constituents measured were however, not significantly (P>0.05) affected by the dietary treatments. For the non-pregnant sheep, the overall mean sodium and potassium values recorded were 290.8 ± 11.2 ana 25.04 ± 0.49 mg/100 ml respectively. For the pregnant sheep the overall mean sodium and potassium values recorded were 328 ± 15.94 and 24.62 ± 0.50 mg/lOO ml respectively. The period of sampling had no significant (P>0.05) effect on the levels of blood constituents measured. Stage of pregnancy significantly (P<0.0l) affected the levels of total protein, globulin, total leucocytes, haemoglobin, alkaline phosphatase, inorganic phosphorus and sodium in the blood while the levels of the other blood constituents measured were not significantly (P>0.05) affected. From the above results, it is concluded that diets containing CPH up to 600 g/Kg DM and 5 NaOH-treated corn cob can be fed to sheep without adversely affecting their growth, feed conversion efficiency, physiology and reproductive performance.

Source: KNUST