Trop Anim Health Prod (2016) 48:367–372 DOI 10.1007/s11250-015-0960-y
REGULAR ARTICLES
Performance of feedlot lambs fed palm kernel cake-based diets Rozilda da Conceição dos Santos 1 & Kaliandra Souza Alves 1 & Rafael Mezzomo 1 & Luis Rennan Sampaio Oliveira 1 & Darley Oliveira Cutrim 1 & Daiany Iris Gomes 1 & Gilmara Pinto Leite 1 & Marcio Yuri de Souza Araújo 1
Received: 17 August 2015 / Accepted: 11 November 2015 / Published online: 2 December 2015 # Springer Science+Business Media Dordrecht 2015
Abstract Fifty-four castrated male lambs with an average body weight of 23 ± 0.35 kg were randomly assigned to five treatments that consisted of different levels of palm kernel cake in the diet (0.0, 7.5, 15.0, 22.5, and 30.0 % on a DM basis) in order to evaluate the effects on intake, digestibility, empty body weight, and body gain composition. The intakes of dry matter, organic matter, crude protein, and non-fiber carbohydrates (NFC) presented with a decreasing linear effect. However, the intakes of EE and NDF presented with increased linear results as the palm kernel cake was added to the concentrate. There was a quadratic effect for the digestibility coefficient of all nutrients, except for NFC. The palm kernel cake had a decreasing linear effect on final body weight, empty body weight, and the average daily gain of the animals that were fed increased levels of palm kernel cake. The inclusion of palm kernel cake as a partial substitute for concentrate decreases the intake of the majority of nutrients, except for EE and NDF, and consequently, causes deleterious effects on the nutrient digestibility and performance of lambs that are fed a 50:50 roughage/concentrate ratio.
Keywords Body composition . By-product . Elaeis guineensis jacq . Nutrition . Ruminant
* Daiany Iris Gomes [email protected] 1
Department of Animal Science, Federal Rural University of Amazon, PA 275, km 13, Parauapebas, Pará 68515-000, Brazil
Introduction Changes in the feeding habits of contemporaneous populations involve demands on the agricultural sector, especially animal feed production. Among the criteria that are evaluated by consumers are animal welfare, feed security, and feed quality (Binnie et al. 2014; McNeill. 2014). Due to these requirements, farmers need to improve their production systems to become more competitive. Feedlots are an alternative, although feeding costs become expensive, which generates the need for scientific studies on alternative feeds that lead to lower costs of the diets and while maintaining high performance levels. In this scenario, several by-products have been evaluated as alternatives to standard feedstuffs (Lage et al. 2014); of those that are available, palm kernel cake, which is a product from the processing of Elaeis guineenses jacq palm oil, has been highlighted due to its availability in the market (Maciel et al. 2012). The fruit’s seed yields the byproduct palm kernel cake, whose proximate composition seems promising with regard to being utilized in diets for ruminants because it contains, on average, 15 % crude protein, 61 % neutral detergent fiber, and 10 % ether extract (Valadares Filho et al. 2015). Considering these values, two hypotheses can be established for the utilization of palm kernel cake. First, it can be included as a roughage ingredient in diets due to the high NDF content, and second, it can be included as a concentrate due to the physical characteristics, which are similar to those of the concentrate ingredients mainly in relation to particle size, amount of protein, and fat. When considering these characteristics, some questions arise such as the following: What is the proportion of palm kernel cake, and which fraction of the diet for ruminants would be replaced, roughage or concentrate? In the literature, data revealed that the replacement of elephant grass with up to
368
80 % palm kernel cake (80 % of total DM) reduced the DM and nutrient intake by 40 % (Bringel et al. 2011). Also, data indicated that the replacement of concentrate (80 % of total DM) with palm kernel cake might have an adverse effect on growth performance and carcass quality in goats (Abubakr et al. 2013). Based on the literature that was consulted, the proportion of palm kernel cake that should be utilized is controversial, mainly because the DM intake was altered as the replacement levels of standard feedstuff with palm kernel cake were increased. In this study, the aim was to evaluate the effects of the replacement of concentrate with palm kernel cake in the diets of growing sheep on nutritional and production parameters.
Materials and methods The experiment was conducted in the sheep section of the Universidade Federal Rural da Amazônia (UFRA). Fifty-four woolless castrated male Santa Inês crossbred sheep with 23 ± 0.35 kg average body weight. The animals were taken to a feedlot, where they were weighed, identified, and were then adapted to the experimental diet and the feedlot facilities for 20 days. Nine animals were randomly selected and slaughtered to estimate the empty body weight. The remaining animals (n = 45) were housed in individual stalls for 88 days, and each was provided with a concrete water trough. The experimental design was a completely randomized design with five treatments; the treatments corresponded to the five levels of replacement of concentrate with palm kernel cake in the proportion of 0.0, 7.5, 15.0, 22.5, and 30.0 %, and there were nine replications per treatment (Table 1). The diets were formulated with a roughage:concentrate ratio of 50:50 in order to meet the average daily gain requirements of 200 g/animal/day (NRC 2007). Elephant grass silage (Pennisetum purpureum Schum. cv. Roxo) with 75 days of regrowth was utilized to perform the surface silage process. The concentrate was composed of soybean meal, ground corn, palm kernel cake, urea, mineral mix, and limestone (Table 1). The palm kernel cake had the following chemical composition: 92 % DM, 96 % organic matter (OM), 11 % crude protein (CP), 10 % ether extract (EE), 64 % neutral detergent fiber corrected for ash and protein (NDFap), 42 % acid detergent fiber (ADF), 10 % lignin, and 11 % non-fiber carbohydrates (NFC). The diets were provided twice a day at 9 h00 and 16 h00, as a total mixed ration. The control was performed after the animals were submitted to 18 h of fasting at the beginning of the experiment and every 14 days thereafter in order to evaluate the body weight gain of the animals. During the intake measurement periods (68 days), feedstuffs and orts (5 to 10 %) were sampled every 7 days, which were then identified and stored in a freezer at −10 ° C for further chemical analyses. Forty-eight days after
Trop Anim Health Prod (2016) 48:367–372
the beginning of the experimental period during the performance test, the animals were submitted to digestibility assays that were conducted via total fecal collections that lasted for 8 days, of which 3 days were set aside for acclimation of the animals to collection bags and 5 days were set aside for data collection. During this assay, samples of feedstuffs, orts, and feces were collected, after which the material was homogenized and an aliquot of 10 % in relation to the weight of each sample was removed, identified, and stored for further laboratory analyses. The samples were partially dried in a forced ventilation oven at 55 °C for 72 h. In the samples of feedstuffs, orts, and feces, the contents of DM, OM, ash, CP, EE, and lignin were determined (AOAC 1990). In the NDF analysis, the samples were corrected for residual ash (Mertens 2002). The NDF was also corrected for the nitrogenous compounds (Licitra et al. 1996). Non-fibrous carbohydrates were obtained by using the equation NFC % = OM − [(CP-CPu + Ur) + EE + NDF ap] where OM = organic matter, CPu = CP derived from urea (% of DM), and Ur = urea content in the diet (% of DM), according to Detmann and Valadares Filho (2010). The coefficients of in vivo apparent digestibility for DM, CP, EE, NDF, TC, and NFC were obtained by determining the difference between the amount of nutrients that were ingested and that were excreted in the feces. The total digestible nutrient intake was obtained by the formula TDN = digestible CP+(digestible EE × 2.25) + digestible TC. At the end of the experiment, two lambs from each treatment were randomly selected for slaughter after an 18 h solid fasting period. The animals were slaughtered according to procedures recommended by the Sanitary and Industrial Inspection Regulation for Animal Origin Products (Brasil, 1997). After slaughter, the gastrointestinal tract (rumen/reticulum, omasum, abomasum, and small and large intestines) was weighed while it was still full, after which it was then emptied to determine the empty body weight (EBW). To determine the animal’s body composition after slaughter, half of the empty carcasses (proportionally and uniformly consisting of half of the carcass and all of the organs, intestines, feet, head, skin, and the blood that was collected when it bled out) were weighed, frozen, cut with a saw blade, ground, and homogenized. Next, 200-g samples were taken per animal and dried in an oven at 105 °C for 72 h to determine the fat dry matter content. The samples were defatted through successive washings with petroleum ether, thus obtaining the pre-defatted dry matter, which was subsequently processed in a ball mill and placed in plastic flasks for further analyses. Analyses of the composite samples from the empty animal bodies followed the methods described by the AOAC (1990). The regression analysis of the variables was performed as a function of the inclusion of palm kernel cake in the experimental diets. The linear and quadratic models were tested for model significance (P < 0.05) and the biological specificity of
Trop Anim Health Prod (2016) 48:367–372 Table 1 Ingredients and chemical composition of the experimental diets
369
Ingredients composition (g kg−1 of DM)
Proportion of kernel cake (% DM) 0%
7.50 %
15 %
22.5 %
30 %
Elephant silage
500
500
500
500
500
Palm kernel cake Corn meal
– 245
75 196
150 147
225 98
300 44
Soybean meal
240
210
180
150
126
Urea Mineral mixture
3.0 10.0
6.0 10.0
9.0 10.0
12.0 10.0
14.0 10.0
Limestone calcitic Chemical composition (g kg−1 of DM) Dry matter Organic matter
2.0
3.0
4.0
5.0
6.0
556 928
563 928
567 926
571 925
574 923
Crude protein Ether extract Neutral detergent fiberap Acid detergent fiber Lignin
170 28.5 416
168 33.1 453
167 37.8 489
165 42.5 525
163 47.0 562
290 47.2
316 54.2
343 61.2
370 68.2
397 75.3
Non-fibrous carbohydrates
322
281
248
215
182
each of the studied variables. All statistical analyses were conducted by using the Statistical Analysis System (SAS Inst. Inc., Cary, NC, USA) software.
inclusion of palm kernel cake. In relation to the chemical composition based on empty body weight, there was a decreasing linear effect for the contents of water and protein (P < 0.05, Table 4), although EE content increased and ash content was not altered as a function of the diets.
Results The dry matter intake (DMI) presented with a decreasing linear effect (P < 0.05), where for every 1 % of palm kernel cake that was added to the diet, the DMI decreased by 11.6 g (Table 2). The same effect can be observed for DMI data in relation to the body weight (BW). Meanwhile, there was a decreasing linear effect in relation to the intakes of OM, CP, TC, and NFC (P < 0.05, Table 2). The maximum TDN intake was associated with the inclusion level of 7.9 % of palm kernel cake in the diet, and it had a quadratic effect. Meanwhile, the intakes of EE and NDF, expressed in grams per day and %BW, increased linearly (Table 2). The digestibility coefficients of DM, OM, CP, TC, NDFap, and TDN presented with a quadratic effect (P < 0.05, Table 3). The digestibility coefficient of NFC presented with a decreasing linear effect (P < 0.05) with the inclusion of palm kernel cake. However, the digestibility coefficient of EE increased linearly (P < 0.05). The inclusion of increasing levels of palm kernel cake yielded a decreasing linear effect on the BW (P < 0.05, Table 4), and the same effect was observed for empty body weight and ADG of the animals. There was a decreasing linear effect (P < 0.05, Table 4) in the amounts of water, ash, EE, and CP that compose the empty body weight as a function of the
Discussion The reduction in DMI can be influenced by several factors such as the degree of rancidity of feedstuffs with high levels of EE, significant increases in the intake of EE, and/or significant increases in NDF. First, although the palm kernel cake may have been stored in a room that was dry, well ventilated, and without light interference, it is possible that the fats became rancid. Second, in this study, it was verified that the maximum EE intake was 51.1 g/day DM (Table 1) which, despite the fact that it is not very high, may have caused negative effects on DMI. Another possible factor that could cause negative effect on intake, was the increase in the levels of urea as increased levels of palm kernel cake (Table 1). The third hypothesis, and probably the best explanation for the reduction in DMI with the inclusion of palm kernel cake, was the increase in NDF intake of the diets (Table 2), which can be related to the rumen-filling effect caused by the physical limit. The increased digesta mass and volume in the rumen negatively interfered with voluntary intake by altering the digesta’s specific gravity (Whetsell et al. 2004), which then caused a negative impact on passage kinetics and contributed to the reduction in feed intake (Penner et al. 2011). Therefore,
370 Table 2 Standard error of mean (SEM), P value and mean daily intake of the experimental diets in gram per day (g/day)
Trop Anim Health Prod (2016) 48:367–372
Item
Proportion of kernel cake (% DM)
P valuea L
30 %
Q
0%
7.50 %
15 %
Dry matterb
1310
1320
1250
1060
1010
21.1
REGULAR ARTICLES
Performance of feedlot lambs fed palm kernel cake-based diets Rozilda da Conceição dos Santos 1 & Kaliandra Souza Alves 1 & Rafael Mezzomo 1 & Luis Rennan Sampaio Oliveira 1 & Darley Oliveira Cutrim 1 & Daiany Iris Gomes 1 & Gilmara Pinto Leite 1 & Marcio Yuri de Souza Araújo 1
Received: 17 August 2015 / Accepted: 11 November 2015 / Published online: 2 December 2015 # Springer Science+Business Media Dordrecht 2015
Abstract Fifty-four castrated male lambs with an average body weight of 23 ± 0.35 kg were randomly assigned to five treatments that consisted of different levels of palm kernel cake in the diet (0.0, 7.5, 15.0, 22.5, and 30.0 % on a DM basis) in order to evaluate the effects on intake, digestibility, empty body weight, and body gain composition. The intakes of dry matter, organic matter, crude protein, and non-fiber carbohydrates (NFC) presented with a decreasing linear effect. However, the intakes of EE and NDF presented with increased linear results as the palm kernel cake was added to the concentrate. There was a quadratic effect for the digestibility coefficient of all nutrients, except for NFC. The palm kernel cake had a decreasing linear effect on final body weight, empty body weight, and the average daily gain of the animals that were fed increased levels of palm kernel cake. The inclusion of palm kernel cake as a partial substitute for concentrate decreases the intake of the majority of nutrients, except for EE and NDF, and consequently, causes deleterious effects on the nutrient digestibility and performance of lambs that are fed a 50:50 roughage/concentrate ratio.
Keywords Body composition . By-product . Elaeis guineensis jacq . Nutrition . Ruminant
* Daiany Iris Gomes [email protected] 1
Department of Animal Science, Federal Rural University of Amazon, PA 275, km 13, Parauapebas, Pará 68515-000, Brazil
Introduction Changes in the feeding habits of contemporaneous populations involve demands on the agricultural sector, especially animal feed production. Among the criteria that are evaluated by consumers are animal welfare, feed security, and feed quality (Binnie et al. 2014; McNeill. 2014). Due to these requirements, farmers need to improve their production systems to become more competitive. Feedlots are an alternative, although feeding costs become expensive, which generates the need for scientific studies on alternative feeds that lead to lower costs of the diets and while maintaining high performance levels. In this scenario, several by-products have been evaluated as alternatives to standard feedstuffs (Lage et al. 2014); of those that are available, palm kernel cake, which is a product from the processing of Elaeis guineenses jacq palm oil, has been highlighted due to its availability in the market (Maciel et al. 2012). The fruit’s seed yields the byproduct palm kernel cake, whose proximate composition seems promising with regard to being utilized in diets for ruminants because it contains, on average, 15 % crude protein, 61 % neutral detergent fiber, and 10 % ether extract (Valadares Filho et al. 2015). Considering these values, two hypotheses can be established for the utilization of palm kernel cake. First, it can be included as a roughage ingredient in diets due to the high NDF content, and second, it can be included as a concentrate due to the physical characteristics, which are similar to those of the concentrate ingredients mainly in relation to particle size, amount of protein, and fat. When considering these characteristics, some questions arise such as the following: What is the proportion of palm kernel cake, and which fraction of the diet for ruminants would be replaced, roughage or concentrate? In the literature, data revealed that the replacement of elephant grass with up to
368
80 % palm kernel cake (80 % of total DM) reduced the DM and nutrient intake by 40 % (Bringel et al. 2011). Also, data indicated that the replacement of concentrate (80 % of total DM) with palm kernel cake might have an adverse effect on growth performance and carcass quality in goats (Abubakr et al. 2013). Based on the literature that was consulted, the proportion of palm kernel cake that should be utilized is controversial, mainly because the DM intake was altered as the replacement levels of standard feedstuff with palm kernel cake were increased. In this study, the aim was to evaluate the effects of the replacement of concentrate with palm kernel cake in the diets of growing sheep on nutritional and production parameters.
Materials and methods The experiment was conducted in the sheep section of the Universidade Federal Rural da Amazônia (UFRA). Fifty-four woolless castrated male Santa Inês crossbred sheep with 23 ± 0.35 kg average body weight. The animals were taken to a feedlot, where they were weighed, identified, and were then adapted to the experimental diet and the feedlot facilities for 20 days. Nine animals were randomly selected and slaughtered to estimate the empty body weight. The remaining animals (n = 45) were housed in individual stalls for 88 days, and each was provided with a concrete water trough. The experimental design was a completely randomized design with five treatments; the treatments corresponded to the five levels of replacement of concentrate with palm kernel cake in the proportion of 0.0, 7.5, 15.0, 22.5, and 30.0 %, and there were nine replications per treatment (Table 1). The diets were formulated with a roughage:concentrate ratio of 50:50 in order to meet the average daily gain requirements of 200 g/animal/day (NRC 2007). Elephant grass silage (Pennisetum purpureum Schum. cv. Roxo) with 75 days of regrowth was utilized to perform the surface silage process. The concentrate was composed of soybean meal, ground corn, palm kernel cake, urea, mineral mix, and limestone (Table 1). The palm kernel cake had the following chemical composition: 92 % DM, 96 % organic matter (OM), 11 % crude protein (CP), 10 % ether extract (EE), 64 % neutral detergent fiber corrected for ash and protein (NDFap), 42 % acid detergent fiber (ADF), 10 % lignin, and 11 % non-fiber carbohydrates (NFC). The diets were provided twice a day at 9 h00 and 16 h00, as a total mixed ration. The control was performed after the animals were submitted to 18 h of fasting at the beginning of the experiment and every 14 days thereafter in order to evaluate the body weight gain of the animals. During the intake measurement periods (68 days), feedstuffs and orts (5 to 10 %) were sampled every 7 days, which were then identified and stored in a freezer at −10 ° C for further chemical analyses. Forty-eight days after
Trop Anim Health Prod (2016) 48:367–372
the beginning of the experimental period during the performance test, the animals were submitted to digestibility assays that were conducted via total fecal collections that lasted for 8 days, of which 3 days were set aside for acclimation of the animals to collection bags and 5 days were set aside for data collection. During this assay, samples of feedstuffs, orts, and feces were collected, after which the material was homogenized and an aliquot of 10 % in relation to the weight of each sample was removed, identified, and stored for further laboratory analyses. The samples were partially dried in a forced ventilation oven at 55 °C for 72 h. In the samples of feedstuffs, orts, and feces, the contents of DM, OM, ash, CP, EE, and lignin were determined (AOAC 1990). In the NDF analysis, the samples were corrected for residual ash (Mertens 2002). The NDF was also corrected for the nitrogenous compounds (Licitra et al. 1996). Non-fibrous carbohydrates were obtained by using the equation NFC % = OM − [(CP-CPu + Ur) + EE + NDF ap] where OM = organic matter, CPu = CP derived from urea (% of DM), and Ur = urea content in the diet (% of DM), according to Detmann and Valadares Filho (2010). The coefficients of in vivo apparent digestibility for DM, CP, EE, NDF, TC, and NFC were obtained by determining the difference between the amount of nutrients that were ingested and that were excreted in the feces. The total digestible nutrient intake was obtained by the formula TDN = digestible CP+(digestible EE × 2.25) + digestible TC. At the end of the experiment, two lambs from each treatment were randomly selected for slaughter after an 18 h solid fasting period. The animals were slaughtered according to procedures recommended by the Sanitary and Industrial Inspection Regulation for Animal Origin Products (Brasil, 1997). After slaughter, the gastrointestinal tract (rumen/reticulum, omasum, abomasum, and small and large intestines) was weighed while it was still full, after which it was then emptied to determine the empty body weight (EBW). To determine the animal’s body composition after slaughter, half of the empty carcasses (proportionally and uniformly consisting of half of the carcass and all of the organs, intestines, feet, head, skin, and the blood that was collected when it bled out) were weighed, frozen, cut with a saw blade, ground, and homogenized. Next, 200-g samples were taken per animal and dried in an oven at 105 °C for 72 h to determine the fat dry matter content. The samples were defatted through successive washings with petroleum ether, thus obtaining the pre-defatted dry matter, which was subsequently processed in a ball mill and placed in plastic flasks for further analyses. Analyses of the composite samples from the empty animal bodies followed the methods described by the AOAC (1990). The regression analysis of the variables was performed as a function of the inclusion of palm kernel cake in the experimental diets. The linear and quadratic models were tested for model significance (P < 0.05) and the biological specificity of
Trop Anim Health Prod (2016) 48:367–372 Table 1 Ingredients and chemical composition of the experimental diets
369
Ingredients composition (g kg−1 of DM)
Proportion of kernel cake (% DM) 0%
7.50 %
15 %
22.5 %
30 %
Elephant silage
500
500
500
500
500
Palm kernel cake Corn meal
– 245
75 196
150 147
225 98
300 44
Soybean meal
240
210
180
150
126
Urea Mineral mixture
3.0 10.0
6.0 10.0
9.0 10.0
12.0 10.0
14.0 10.0
Limestone calcitic Chemical composition (g kg−1 of DM) Dry matter Organic matter
2.0
3.0
4.0
5.0
6.0
556 928
563 928
567 926
571 925
574 923
Crude protein Ether extract Neutral detergent fiberap Acid detergent fiber Lignin
170 28.5 416
168 33.1 453
167 37.8 489
165 42.5 525
163 47.0 562
290 47.2
316 54.2
343 61.2
370 68.2
397 75.3
Non-fibrous carbohydrates
322
281
248
215
182
each of the studied variables. All statistical analyses were conducted by using the Statistical Analysis System (SAS Inst. Inc., Cary, NC, USA) software.
inclusion of palm kernel cake. In relation to the chemical composition based on empty body weight, there was a decreasing linear effect for the contents of water and protein (P < 0.05, Table 4), although EE content increased and ash content was not altered as a function of the diets.
Results The dry matter intake (DMI) presented with a decreasing linear effect (P < 0.05), where for every 1 % of palm kernel cake that was added to the diet, the DMI decreased by 11.6 g (Table 2). The same effect can be observed for DMI data in relation to the body weight (BW). Meanwhile, there was a decreasing linear effect in relation to the intakes of OM, CP, TC, and NFC (P < 0.05, Table 2). The maximum TDN intake was associated with the inclusion level of 7.9 % of palm kernel cake in the diet, and it had a quadratic effect. Meanwhile, the intakes of EE and NDF, expressed in grams per day and %BW, increased linearly (Table 2). The digestibility coefficients of DM, OM, CP, TC, NDFap, and TDN presented with a quadratic effect (P < 0.05, Table 3). The digestibility coefficient of NFC presented with a decreasing linear effect (P < 0.05) with the inclusion of palm kernel cake. However, the digestibility coefficient of EE increased linearly (P < 0.05). The inclusion of increasing levels of palm kernel cake yielded a decreasing linear effect on the BW (P < 0.05, Table 4), and the same effect was observed for empty body weight and ADG of the animals. There was a decreasing linear effect (P < 0.05, Table 4) in the amounts of water, ash, EE, and CP that compose the empty body weight as a function of the
Discussion The reduction in DMI can be influenced by several factors such as the degree of rancidity of feedstuffs with high levels of EE, significant increases in the intake of EE, and/or significant increases in NDF. First, although the palm kernel cake may have been stored in a room that was dry, well ventilated, and without light interference, it is possible that the fats became rancid. Second, in this study, it was verified that the maximum EE intake was 51.1 g/day DM (Table 1) which, despite the fact that it is not very high, may have caused negative effects on DMI. Another possible factor that could cause negative effect on intake, was the increase in the levels of urea as increased levels of palm kernel cake (Table 1). The third hypothesis, and probably the best explanation for the reduction in DMI with the inclusion of palm kernel cake, was the increase in NDF intake of the diets (Table 2), which can be related to the rumen-filling effect caused by the physical limit. The increased digesta mass and volume in the rumen negatively interfered with voluntary intake by altering the digesta’s specific gravity (Whetsell et al. 2004), which then caused a negative impact on passage kinetics and contributed to the reduction in feed intake (Penner et al. 2011). Therefore,
370 Table 2 Standard error of mean (SEM), P value and mean daily intake of the experimental diets in gram per day (g/day)
Trop Anim Health Prod (2016) 48:367–372
Item
Proportion of kernel cake (% DM)
P valuea L
30 %
Q
0%
7.50 %
15 %
Dry matterb
1310
1320
1250
1060
1010
21.1
