Livestock Research for Rural Development 20 (11) 2008 | Guide for preparation of papers | LRRD News | Citation of this paper |
To compare the feeding value of wheat straw (WS) and cottonseed hulls (CSH) based complete diets in mash and flaked forms, 15 crossbred male calves were divided into 3 groups of 5 each and fed on complete diets (CP 12%, TDN 55%) consisting roughage and concentrate mixture in the ratio of 60: 40. Group I was fed on WS based diet in mash form (WS-M) while groups II and III were fed on CSH based complete diet in flaked (CSH-F) and mash form (CSH-M), ad lib, respectively. Additionally, similar quantity of non-leguminous green fodder was offered to all the groups throughout the experimental period of 120 days.
Daily DM intake (kg/100 kg BW) was higher (P < 0.05) in CSH-F (3.55 kg) and CSH-M (3.55 kg) than in WS-M (2.78 kg). Average daily body weight gain was also higher (P < 0.05) in CSH-F (586 g) and CSH-M (533 g) than in WS-M (245 g), resulting in higher (P < 0.05) feed conversion efficiency in CSH-F (8.49) and CSH-M (9.29) than in WS-M (15.6), however, variations between the CSH-F and CSH-M for DMI and body weight gain were non-significant. CP digestibility was higher (P < 0.05) in WS-M (69.3%) than in CSH-F (54.2 %) and CSH-M (56.3%) and the variation between later groups was not significant. Digestibility of cell wall constituents except cellulose did not vary significantly among the groups, however, values were higher (P > 0.05) in CSH-M than in CSH-F. Intake of digestible OM, CP and NDF was higher (P < 0.05) in CSH-F and CSH-F than in WS-M. DCP content of WS-M (8.75%) was higher (P < 0.05) than CSH-F and CSH-M (6.94 and 7.39%, respectively), however, TDN content of all the diets was similar (about 55%). DCP intake was 21.3 and 28.3 per cent higher in CSH-F and CSH-M than WS-M and TDN intake was 55.8 and 70.2 per cent higher in CSH-F and CSH-M than WS-M. All the groups were in positive balances of N, Ca and P, however, balance of N was higher (P < 0.05) in CSH-F (40.2 g/day) and CSH-M (42.5 g/day) than in WS-M (26.0 g/day).
It can be concluded that feeding of cottonseed hulls (60%) based complete diets (CP 12%, TDN 55%) in crossbred calves improved (P < 0.05) growth rate and nutrient utilization than WS based complete diet. Flaking of CSH based complete diet improved the bulk density (about 85%), feed intake and growth performance over respective mash diet but improvement was not significant. Keeping in view the easy handling of feed in flaked form, flaking process of CSH based complete diet is recommended.
Key words: Complete diets, cottonseed hulls, crossbred calves, growth, nutrient utilization
India has large livestock population and the requirement of nutrients for the livestock was more than the availability (Jain et al 1996). Even the availability of roughages is lower than the requirement. Therefore, newer feed resources including agro-industrial byproducts and agricultural wastes have to be utilized judiciously to bridge the gap between the availability and requirement of nutrients. Recently emphasis is being given on the food processing industry in India, which may result in large availability of wastes, having the potential of animal feeding. Cottonseed hull (CSH) is one of such waste material resulting from decortication of cottonseeds. Is there an estimate for availability or the potential availability in the country?The availability of cottonseed hulls in India is around 17 lakh tons Complete feed is a recent development in which roughages and concentrate mixture are mixed thoroughly followed by its processing in pellet or block form. Dry roughages mainly wheat straw (WS) has to be ground before pelleting the complete feed, which requires large infrastructure and their handling is difficult. Cottonseed hull (CSH), a fibrous material having low CP and high lignin contents can be used as a source of roughage in the ration of ruminants (Reddy and Reddy 1998a). Due to its different physical nature and higher bulk density (Reddy and Reddy 1990) than wheat straw, it requires no further processing for it’s mixing with other ingredients and the diets containing CSH can be densified for easy handling and lowering the cost of transportation and storage (Anderson et al 1988). Further, processing of CSH based complete feeds may improve its utilization resulting in improved performance of livestock (Ibrahim et al 1998, Reddy and Reddy 1998b). Since blocking/pelleting of complete feed requires large infrastructure, flaking of diet, particularly based on CSH may be an economical option, for which simple oil expeller unit may be employed, moreover, farmers and animals both are already familiar with flaked material. A study was therefore, conducted to compare the feeding value of wheat straw and CSH based complete diets in mash and flaked forms on the feed intake, nutrients utilization and growth performance of crossbred calves.
Fifteen crossbred (Karan Swiss and Karan Fries) male calves (6-8 months) were selected and randomly distributed into 3 groups of 5 each. Group I was fed on WS based complete diet (WS-M) having roughage: concentrate ratio of 60: 40. While groups II and III were fed on CSH based complete diet in flaked (CSH-F) and mash form (CSH-M). CSH-F was prepared by passing the mashed material through a mechanical oil expelling unit. All the complete diets were isonitrogenous (12% CP) and isocaloric (55% TDN). Ingredient composition of experimental complete diets is presented in Table1.
Table 1. Ingredient, physical and chemical composition of feeds and fodder |
||||
Particulars |
WS-M |
CSH-F |
CSH-M |
Green fodder |
Ingredient composition (%) |
||||
Wheat straw |
60.0 |
- |
- |
|
Cottonseed hulls |
- |
60.0 |
60.0 |
|
Molasses |
10.0 |
10.0 |
10.0 |
|
Mustard oil cake |
12.5 |
10.0 |
10.0 |
|
Barley |
10.0 |
11.0 |
11.0 |
|
DORB |
5.0 |
6.5 |
6.5 |
|
Urea |
1.0 |
1.0 |
1.0 |
|
Salt |
0.5 |
0.5 |
0.5 |
|
Mineral mixture |
1.0 |
1.0 |
1.0 |
|
Physical characteristic |
|
|
|
|
Bulk density, kg/m3 |
186 |
470 |
254 |
|
Texture |
mash |
Flakes |
mash |
|
Chemical composition (% DM basis) |
||||
Organic matter |
87.2 |
92.6 |
93.7 |
88.0 |
Crude protein |
12.6 |
12.8 |
13.1 |
10.0 |
Ether extract |
3.84 |
3.75 |
3.08 |
6.20 |
NDF |
57.6 |
62.4 |
65.5 |
73.6 |
ADF |
35.4 |
42.5 |
43.7 |
39.9 |
Hemi-cellulose |
22.3 |
19.9 |
21.8 |
33.7 |
Cellulose |
27.8 |
21.7 |
26.8 |
27.4 |
ADL |
6.06 |
20.5 |
16.5 |
11.6 |
Calcium |
0.51 |
0.42 |
0.40 |
0.07 |
Phosphorus |
0.43 |
0.49 |
0.47 |
0.05 |
What is the reason for lower cellulose, hemicellulose and higher lignin contents between the two CSH based diets as the ingredient composition is same? Lowering of cellulose and hemicellulose in CSH-F diet compared to CSH-M diet as a result of processing of CSH based diet into flakes may be attributed to the mechanical pressure and frictional heat, generated during the course of flaking, (Wainman and Blaxter 1972) |
Both the CSH based complete diets were made in bulk for whole of the experimental period, however, diet of group I was prepared daily and mixed manually. All the experimental animals were offered respective complete diets ad lib and additionally 2 kg non-leguminous green fodder was supplied to each animal daily to meet the vitamin A requirement. Body weight of experimental animals recorded before access to feed and water at fortnightly interval for two consecutive days during the experimental period of 120 days. Feed intake of individual animal was recorded twice a week. A metabolism trial (7 days) was conducted after completing 105 days of experimental feeding. Samples of feed, left over and faeces were analysed for proximate principles (AOAC 1990) and cell wall constituents (Goering and Van Soest, 1970). Urine samples were analyzed for N and P (AOAC 1990) and Ca using atomic absorption spectrophotometer (AAS Pye Unicam, England). Data were analysed as per Randomized Block Design and treatment means were compared by calculating critical difference as per Snedecor and Cochran (1986).
Bulk density of CSH based complete diets (254 and 470 kg/m3) was higher than WS based diet (186 kg/m3) (Table 1), further bulk density of CSH based flaked diet was about 85% higher than CSH based mash diet. All the three complete were isonitrogenous (about 12% CP) as per the experimental plan. Cell wall constituents were higher in CSH based complete diets than in WS based diet, which may be due to higher cell wall constituents of CSH than WS (Table 1). ADF-N in CSH was 0.63 per cent (about 80% of total nitrogen).
Mean daily DM intake was 30 per cent higher (P < 0.05) in CSH-F and CSH-M than in WS-M and variation between the CSH-F and CSH-M was not significant (Table 2).
Table 2. DM intake and growth performance of crossbred calves fed on different treatment diets |
||||
Particulars |
WS-M |
CSH-F |
CSH-M |
P |
Average initial BW, kg |
127±20.09 |
113±8.80 |
116±6.59 |
-- |
Average final BW, kg |
156±20.40 |
183±5.54 |
180±5.33 |
???-- |
Total live weight gain, kg |
29.5±1.43a |
70.3±3.36b |
64.0±3.33b |
** |
Average daily gain, g |
245±11.88a |
586±28.04b |
533±26.09b |
** |
DM intake |
||||
Complete diet, kg/day |
3.50±0.37a |
4.72±0.03b |
4.70±0.01b |
** |
Green fodder, kg/day |
0.49±0.01a |
0.48±0.01b |
0.49±0.00a |
* |
Total DMI, kg/d |
3.99±0.38a |
5.20±0.03b |
5.19±0.02b |
** |
DMI, kg/100 kg BW |
2.78±0.14a |
3.55±0.17b |
3.55±0.15b |
** |
DMI, g/kg W0.75 |
95.5±2.28a |
124±4.42b |
124±3.86b |
** |
Feed conversion efficiency, kg DMI/kg gain |
15.61±1.64a |
8.49±0.41b |
9.29±4.04b |
** |
a, b Values bearing different superscripts in row differ significantly (P < 0.05)
NS = Non-significant; *
Significant at (P < 0.05); ** Significant at (P < 0.01) |
Higher DM intake in CSH-F and CSH-M may be attributed to fine particle size of CSH based diets and thorough mixing, however, flaking did not exhibit any additional advantage. DM intake per 100 kg BW was higher particularly in CSH-F and CSH-M than that recommended by Kearl (1982). Reddy and Reddy (1983) and Reddy and Reddy (1990) also observed higher DM intake from CSH based complete diets than conventional diet. Similar to these observations, Reddy and Reddy (1990) reported that processing of CSH based diets into pellets did not influence the DM intake in sheep and goats.
Digestibility of DM and OM was lower (P > 0.05) in CSH-F than in other groups (Table 3), which showed that increasing the bulk density of diet through the process of flaking enhanced the fractional passage rate of solid digesta through the reticulo-rumen as recorded in another experiment (Ramachandran and Singhal 2002).
Table 3. Nutrient digestibility and intake of digestible nutrients in crossbred calves |
|||||
Particulars |
WS-M |
CSH-F |
CSH-M |
P |
|
Digestibility coefficient of nutrients, % |
|||||
Dry matter |
58.8±3.77 |
54.9±2.57 |
59.1±3.71 |
NS |
|
Organic matter |
59.4±3.70 |
55.1±2.47 |
59.9±3.65 |
NS |
|
Crude protein |
69.3±5.08a |
54.2±2.09b |
56.3±3.87b |
** |
|
Ether extract |
85.0±2.59 |
75.0±2.67 |
74.5±4.52 |
NS |
|
NDF |
46.4±5.02 |
43.9±3.28 |
51.4±4.84 |
NS |
|
ADF |
40.6±6.41 |
37.6±3.85 |
45.4±5.65 |
NS |
|
Hemi-cellulose |
54.9±3.22 |
56.7±2.41 |
62.8±3.31 |
NS |
|
Cellulose |
64.1±2.48ab |
59.2±2.27a |
68.8±2.78b |
* |
|
Intake of digestible nutrients |
|||||
DOMI, kg/d |
2.03 ± 0.31a |
3.18 ± 0.14b |
3.48 ± 0.23b |
* * |
|
DCPI, g/d |
353 ± 38.64a |
428 ± 16.50b |
453 ± 33.99b |
* |
|
DNDFI, kg/d |
1.06 ± 0.23a |
1.73 ± 0.13b |
2.11 ± 0.21b |
* * |
|
TDN intake, kg/d |
2.15 ± 0.33a |
3.35 ± 0.15b |
3.66 ± 0.24b |
* * |
|
Nutritive value, % |
|||||
DCP |
8.75 ± 0.38a |
6.94 ± 0.27b |
7.39 ± 0.56b |
* * |
|
TDN |
54.4 ± 3.38 |
53.6 ± 2.40 |
58.9 ± 3.85 |
NS |
|
a, b Values bearing different superscripts in row differ significantly NS = Non-significant; * Significant at (P < 0.05); ** Significant at (P < 0.01) |
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|
|
|
|
|
|
Similar to these results, Mehta and Singhal (1983, 1984) and Lohan and Rathee (1983) also reported that pelleting of agro-industrial byproducts based diets increased the DM intake but decreased nutrients digestibility. Reddy and Reddy (1991) also reported similar variation in DM digestibility in CSH based (40%) mash and pelleted diets. CP digestibility of WS based diet was higher than CSH based diets and the CP digestibility of mash and flaked diets was statistically similar. Lower CP digestibility of CSH based diets may be attributed to the higher ADF-N or tannins content of CSH. Moreover lower CP intake in WS-M may be attributed for the lower DM intake i.e., lower N intake in comparison to CSH-F and CSH-M. There was no significant variation among the groups for EE digestibility.
Non-significant variation among the groups for the digestibility of cell wall constituents such as NDF, ADF and hemi-cellulose (Table 3) revealed that higher lignin content of CSH did not affect the utilization of other cell wall fractions. Higher cellulose digestibility of CSH based complete diets than WS based diet may be attributed to the higher cellulose content of CSH due to the presence of residual lint which is highly digestible. (The table indicates similar cellulose contents in the three diets) Though the cellulose content may be similar, the cellulose present in the wheat straw is bound to the lignin hence the digestibility is low, while the residual lint present in the CSH is in the form of pure cellulose hence the digestibility of cellulose in CSH based diets is higher than that recorded in WS based diets. Higher (P > 0.05) digestibility of cell wall constituents CSH-M than in CSH-F further indicated the higher rate of passage of solid digesta as a result of flaking of diet as recorded earlier (Ramachandran and Singhal 2002). Lohan and Rathee (1983) and Singhal and Mudgal (1983) also reported similar observation following the pelleting of wheat straw based complete diet.
DCP value of complete WS-M, CSH-F and CSH-M was 8.75, 6.94 and 7.39 per cent, respectively and the corresponding value for TDN was 54.4, 53.6 and 58.9 pre cent. Lower DCP content (P < 0.01) of CSH based diets than in WS based diet may be attributed to the higher ADF-N of CSH and /or binding of dietary N with tannin present in the CSH (Farell and Maldonado 2001).
Intake of digestible OM, CP and NDF was higher (P < 0.05) in CSH-F and CSH-M than in WS-M due to the higher feed intake (Table 2). DCP intake was 21.3 and 28.3 per cent higher in CSH-F and CSH-M than in WS-M and variation among the groups was significant (P < 0.05). TDN intake was 55.8 and 70.2 per cent higher in CSH-F and CSH-M than in WS-M (Table 3) due to the higher fibre digestibility in these groups. Higher intake of DCP and TDN on CSH based diets, irrespective of their physical form, than on WS based diet may be attributed to higher feed intake. Reddy and Reddy (1983), Reddy and Reddy (1991), Venkanna et al (1997) and Reddy and Reddy (1998a) also reported similar results.
On comparing the nutrient intake with their requirements suggested by Kearl (1982) and NRC (1989) it was recorded that DM intake in WS-M was almost as per the requirements but in CSH-F and CSH-M it was about 24 per cent higher than the recommended value (Table 4).
Table 4. Comparison of plane of nutrition of crossbred calves with feeding standards* |
|||
Particulars |
WS-M |
CSH-F |
CSH-M |
DMI, kg/d |
3.99 |
5.20 |
5.19 |
Requirement as per Kearl |
4.20 |
4.20 |
4.20 |
Requirement as per NRC |
4.20 |
4.20 |
4.20 |
DCP intake, g/d |
353 |
428 |
453 |
Requirement as per Kearl |
305 |
305 |
305 |
Requirement as per NRC |
300 |
300 |
300 |
TDN intake, kg/) |
2.15 |
3.35 |
3.66 |
Requirement as per Kearl |
2.20 |
2.20 |
2.20 |
Requirement as per NRC |
2.70 |
2.70 |
2.70 |
According to Kearl (1982) and NRC (1989) for 500 g/d body weight gain |
DCP intake in WS-M, CSH-F and CSH-M was 17.7, 42.7 and 51.0 per cent higher than the recommended allowance. However, TDN intake in WS-M was 20 per cent lower than the requirement (NRC 1989) but in CSH-F and CSH-M, TDN intake was 24.0 and 35.6 per cent higher than the value recommended by NRC (1989). Better plane of nutrition in groups fed on CSH based complete diet, irrespective of its physical form, was reflected in higher (P < 0.05) body weight gain and general health of the calves.
Total N intake was higher (P < 0.05) in CSH-F and CSH-M than in WS-M and the contribution of N through roughage portion of respective complete diets was 13.4, 29.3 and 29.2 g/d (Table 5).
Table 5. Nitrogen, calcium and phosphorus balances in crossbred calves |
||||
Particulars |
WS-M |
CSH-F |
CSH-M |
P |
N balance, g/day |
||||
Total N intake |
80.8 ± 5.71a |
126 ± 0.00b |
129 ± 0.77b |
** |
N excretion through faeces |
24.3 ± 1.53a |
57.9 ± 2.64b |
56.2 ± 5.46b |
** |
N excretion through urine |
30.5 ± 2.74 |
28.4 ± 2.31 |
29.8± 1.26 |
NS |
Total N excretion |
54.8 ± 3.52a |
86.3 ± 2.72b |
86.1 ± 5.20b |
* |
N Digested |
56.5 ± 6.18a |
68.5 ± 2.64ab |
72.4 ± 5.44b |
* |
N Retention |
26.0 ± 8.52a |
40.8 ± 2.72b |
42.5 ± 5.65b |
* |
Ca balance, g/day |
||||
Total Ca intake |
20.1 ± 1.25a |
25.2 ± 0.02b |
23.9 ± 0.12b |
* * |
Ca excretion through faeces |
6.43 ± 0.89a |
12.1 ± 1.42b |
10.5 ± 1.44b |
* |
Ca excretion through urine |
3.33 ± 0.24 |
3.10 ± 0.81 |
2.38 ± 0.00 |
NS |
Total Ca excretion |
9.76 ± 0.70a |
15.2 ± 0.69b |
12.9 ± 1.44b |
* |
Ca balance |
10.3 ± 1.46 |
10.0 ± 0.70 |
11.0 ± 1.37 |
NS |
P balance, g/day |
||||
Total P intake |
16.5 ± 1.27a |
29.0 ± 0.00b |
27.8 ± 0.11b |
* * |
P excretion through faeces |
11.0 ± 0.46 |
16.6 ± 1.73 |
14.3 ± 1.95 |
NS |
P excretion through urine |
0.78 ± 0.36 |
1.58 ± 0.07 |
1.16 ± 0.12 |
NS |
Total P excretion |
11.8 ± 0.42a |
18.1 ± 1.74b |
15.5 ± 1.90a |
* |
P balance |
4.77 ± 1.39 a |
10.9 ± 1.74 b |
12.3 ± 1.91b |
* |
a, b Values bearing different superscripts in row differ significantly (P < 0.05) NS = Non-significant; * Significant at (P < 0.05); ** Significant at (P < 0.01) |
Faecal N excretion was higher (P < 0.05) in groups fed on CSH based complete diets obviously due to higher N intake thereby higher ADF-N intake or binding of dietary N to tannins (Farell and Maldonado 2001). It was also evident from these results that flaking of CSH based diet did not affect the N utilization adversely. The quantity of N digested in CSH-F and CSH-M was 17.6 and 22.0 per cent higher than that recorded in WS. All the groups showed positive N balance and CSH-F (40.2 g/day) and CSH-M (42.5 g/day) were in higher (P < 0.05) N balance than WS-M (26 g/day). Higher N balance in CSH-F and CSH-M was a reflection of higher intake of DM and N and their utilization for tissue synthesis and resulted in higher growth rate than in WS. Feeding of CSH based complete diets did not influence the Ca and P utilization in crossbred calves (Table 5). Similar pattern of N, Ca and P balances were also reported by Reddy and Reddy (1990), Venkanna et al (1997) and Reddy and Reddy (1998a) following the feeding of CSH based diet.
Growth of crossbred calves in different groups (Figure 1) showed that calves grew in all the diets consistently, however, growth in CSH-F (586 g) and CSH-M (533 g) was higher (P < 0.05) than in WS-M (245 g), however, variation between the CSH-F and CSH-M was not significant (Table 2). The increase in growth rate was comensurate with the DM intake. Regression coefficients (b) for the body weight gain per day was 0.25, 0.61 and 0.57 in WS-M, CSH-F and CSH-M, respectively. Feed conversion efficiency (kg DMI/kg gain) was higher (P < 0.05) in CSH-F and CSH-M than that recorded in WS-M (Table 2). Obviously due to the higher feed intake and nutrient utilization for growth purpose, which ultimately manifested in higher feed conversion efficiency. Similar increase in growth rate and feed conversion efficiency due to the feeding of CSH based diets was reported by Hale et al (1969), Koeln et al (1984) and Reddy and Reddy (1991). Similar growth rate and feed efficiency in CSH-F and CSH-M indicated that flaking of complete diets did not yield any additional advantage over mash diet.
Why is there no mention of economics of feeding, cost of feeding/day/animal, per kg. gain, cost of processing etc. This may be included if possible. The CSH based feed materials required for the entire feeding trial was supplied by Cottonseed Husk Cake Industries Association, Rajpura, Punjab, India free of cost hence the economics was not worked out at that time.
It can be concluded that feeding of cottonseed hulls (60%) based complete diets improved (P < 0.01) growth rate, feed conversion efficiency and nutrient utilization than wheat straw based complete diet in crossbred calves. Flaking of CSH based complete diet did not yield additional advantage as far as nutrient utilization and growth of calves were concerned, however, this method of processing increased the bulk density of feed (85%) which will reduce the cost of its handling, transportation and storage.
Authors thankfully acknowledge Mr. S L Anand, President and Mr. Dharamvir Kalra, Secretary, Cottonseed Husk Cake Industries Association, Rajpura, Punjab for the supply of cottonseed hulls based complete diets in mash and flaked form.
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Received 4 August 2008; Accepted 28 August 2008; Published 6 November 2008