Feed intake and digestion by two cattle breeds fed of baby corn stovers and groundnut hay supplemented with graded levels of concentrate and Moringa leaves

F S Nouala, S Muetzel*, E Hoffmann*and K Becker*

Africa Union Interafrican Bureau for Animal Resources, Museum Hill, Westlands Rd P.O.Box 30786-00100 Nairobi, Kenya
* Institute for Animal Production in the Tropics and Subtropics (480) University of Hohenheim, Fruwirthstr. 12 D-70593 Stuttgart, Germany
nouala.simplice@au-ibar.org

Abstract

To assess the impact of breeds and diets on animal performance in a West African production setting, pure N’Dama and N’Dama x Jersey crossbred cattle were fed two basal diets, baby corn and groundnut hay, supplemented with graded levels of either conventional concentrate or Moringa oleifera  Lam leaves (moringa), to compare animal responses in productivity. In this context, moringa constitutes a potential alternative to commercial concentrate for cattle production.

Twelve animals (six of each breed) were used in a cross over design. They were fed consecutively three combinations of roughage and supplement, baby corn stovers and concentrate (BCS:C), groundnut hay and concentrate (GNH:C) and groundnut hay and moringa (GNH:M), each at 5 levels of supplementation (0, 10, 20, 30 and 40%). Results from this study showed that there was a clear difference in animal response to different feeding regimes between the two breeds. When averaged over all diets organic matter intake (OMI) was higher in crossbred compared to N’Dama (94 and 87.6 g/kg 0.75 d-1, respectively). Only when the diet consisted of BCS:C, and at low levels of supplementation, N’Dama ingested more than crossbred, but the difference was not significant. With GNH:C crossbred ingested significantly more at levels of supplementation less or equal to 20%. With GNH:M crossbred ingested more, whatever the level of supplementation. Averaged over all diets and levels, organic matter digestibility (OMD) was higher in N’Dama (64.6% against 60.7 in crossbreds).

Results from our study showed that N'Dama might be as efficient as their crossbred counterparts in converting feed into weight although they had the ability to ingest more of low quality feed. When moringa was used as supplement, the results on weight gain were not conclusive, however, data on intake and digestibility showed promising potential for moringa as an alternative to concentrate mixture.

Key words: Gambia, maize, supplementation

Introduction

Rapid urbanization in sub Saharan African countries has become a major motivating force in the transfer of animal science technology, which has expanded into dairy production leading to the need for cattle with higher potential for milk yield than the indigenous breeds (Cunningham and Syrstad 1987; Akinbamijo et al 2003; Nouala et al 2003). Interactions between animal genotypes and environment have been reported (Goetsch and Johnson 1999; Frisch and Vercoe1991). In general, species and breed that have developed in a particular environment are well adapted for survival and (or) meat, milk production depending on the degree and nature of human selection. Therefore, breed from a specific environment may not perform similarly when placed in another setting. In order to make more efficient use of the introduced breeds and available feed resources, there is a need to evaluate the performance of the native local breeds and their crosses with European breed under the local production environment and several scenarios of feed supply.

Conventional concentrates as supplement to poor quality roughage are often non available and not affordable. Moringa oleifera Lam, a promising pantropical multipurpose tree with high crude protein and negligible tannins content (Makkar and Becker 1996), offers a good alternative source of protein to ruminant. The present study was instigated to compare the responses of pure N’Dama and N’Dama x Jersey crosses to two basal diets (Baby corn stovers and Groundnut hay) with graded levels of supplementation and to evaluate the potential of moringa leaves as an alternative to conventional concentrate for cattle production in The Gambia.

Materials and methods 

Animals and housing

The study was carried out at the ITC’s station in Kerr Serigne (in The Gambia) for 18 months (January 2002 to June 2003); twelve bulls (six N’Dama 152 ±12 Kg and six Jersey x N’Dama 295±10 kg) aged between 4- 6 years were used for this study. They were individually housed in pens with concrete floors on an open-air platform. They had free access to saltlick and to water four times a day. Prior to the experiment, animals were dewormed with albendazole (Albenol®- 100, oral Inter chemie, Holland) at the dose of 12 ml/kg BW and were sprayed against ticks with Decatix (Cooper® Zimbabwe Pvt. LTD). They were also tested for trypanosomosis infection using the dark ground buffy coat technique and all the infected animals were treated with diminazene aceturate (Berenil® Hœchst A.G., Frankfurt Am Main, Germany) at the dose of 3.5mg /kg BW. During the experimental period the animals were monitored for tick infection on a weekly basis, and for trypanosomosis infection fortnightly.

Experimental feeds

Roughage

Baby corn stovers (Zea mays L)

The stovers used during the experiment were from early maturing maize the variety Pacific 421. The stovers were cut after harvesting cobs (10 days after flowering) and allowed to wilt in the field for 2-3 days. Thereafter, the maize stovers were bailed, carted to the station and sun-dried naturally in open air. To facilitate intake, the stovers were then mechanically chopped to a length of between 5 and 7 cm before being offered to animals.

Groundnut hay (Arachis hypogaea L)

The hay used in the present study was collected and carted at the station by dealers. Representative samples of each batch were taken for analysis.

Supplements

Concentrate Mixture

This was made from locally available agricultural by-products, i.e. rice bran and groundnut cake (1:1, w:w). The high fibre content of our concentrate mixture was mainly attributed to the high fibre content of the rice bran used for the mixture (65%NDF, 51% ADF), due to high the proportion of husks.

Moringa (Moringa oleifera Lam) leaf meal

The moringa fodder was obtained from the ITC plots (between the latitudes 13o N and 14o N). Moringa in this plot was planted at 20 cm interval in and between the rows (36 plants/m2). The field was irrigated during dry season and 50 to 60 tons per ha of organic manure was applied at the beginning. On a weekly basis, 50kg/ha of inorganic fertilizer NPK (15 15 15) was applied through out the year. The plants were cut at about 30-40 cm above the ground 60 days after plantation or re-growth. The sun dried leaves and less lignified part of the branches were then ground and mixed in an industrial mixer to obtain a homogeneous meal. The chemical composition of moringa (Table1) showed that it had almost two times less NDF and around 6% less CP than the concentrate mixture.

Treatment

Animals from each breed were assigned to 15 different diets (Table 2 a diet is a combination of a basal diet and one level of supplementation) in three different periods in a simple cross over design.

During the first period, baby corn stovers were used as basal, and concentrate mixture as supplement (BCS:Co) at 0%, 10%, 20%, 30% and 40%. For each level of supplementation, the supplement replaced equal proportion of the basal diet in the estimated intake.

After this period the animals were allowed two months resting period and were taking back on the platform for the second period with groundnut hay as basal and concentrate mixture as supplement (GNH:Co). After another resting period they were taken back for the third period with groundnut hay and moringa as supplement (GNH:Mo) were tested.  Each diet (roughage and one level of supplementation) was tested in 24 days with 14 days adaptation period and 10 days data collection period. The combination roughage: supplement was considered as a diet.

Feed intake measurement

The feed was offered at 2.5% body weight in two equal daily portions in the morning and in the afternoon to ensure constant availability. During the adaptation period the average feed intake was measured individually and the bulls were offered this quantity plus 10-20% during the data collection period. Cleaning of the pens, removal and weighing of leftovers from the previous day were done daily before feeding. The roughage (basal diet) was only offered after the animal had completely eaten the supplement. Representative samples of feed offered and of feed refused were taken daily for dry matter determination and bulked per breed for crude nutrients analysis.

The dry matter intake (DMI) on a daily basis was calculated as the difference between the quantity of feed dry matter offered and refused.

In vivo Digestibility

Faeces were manually collected immediately after voided and sub samples weighed at 8.00 h and 20.00 h. The dry matter was determined on a daily basis, and 5% of the representative faeces voided were sampled from each animal kept in a freeze and bulked on a weekly basis until required for further analysis. The percentage dry matter digestibility (DMD) was determined as:

DMD= ((DMI- DM faeces)/DMI)*100.

Where DMI is the total dry matter intake.

Organic matter, NDF and ADF in the faeces were then determined for nutrients digestibility. For organic matter determination faecal samples were incinerated in a muffle furnace at 550°C for 3 hours.

Neutral detergent fibre (NDF) and Acid detergent fibre (ADF) determination

0.5 g of sample were weighed directly into filter bags (ANKOM F57) and placed in the ANKOM fibre analyzer (ANKOM FIBER ANLYZER ^II ANKOM technology, Fairport, New York, USA); for NDF determination, 24 filter bags were boiled in 2 L of neutral detergent solution for 75 min then rinsed three times with hot water and oven dried. ADF was determined by boiling 24 bags in 2 L of acid detergent solution for 60 min.

Weight gain

Body weight was determined at the beginning and the end of each period (24 days) using an electronic scale (JR200 Trust-Test limited New Zealand). Weighing was done after 12 hours of complete starvation. The difference of the two weights was divided by the number of days of the period (24 days) and the results taken as the average daily weight gain

Statistical analysis

Data regarding intake, nutrients digestion and growth were analyzed using the mixed model procedure of SAS, which estimates the variance components using the residual maximum likelihood method. The model used evaluated the effects due to breed, diet, level and their interactions, orthogonal contrasts were used to determine whether the increased level of supplementation had a linear or quadratic effect on the parameters.

The optimum level of supplementation for organic matter digestibility (OMD) and total organic matter intake was estimated using the single-slope broken–line model (Robbins1986) using the NLIN procedure of SAS.
 

Results

Live weights

Crossbred animals were twice as heavy as the purebred N’Dama (Table 3) therefore in the statistical analysis for weight change the data were corrected for metabolic weight (Table 4).

Organic matter and digestible organic intake

Total organic matter intake (TOMI) was on average higher in crossbred. They ingested 6.4 g/kg^.75 d^-1 more than the local N’Dama (Table 4). TOMI was also higher with baby corn stovers diet compared to groundnut hay diets; there was no difference between moringa and concentrate mixture supplementation (Table 4) in both breeds.

However, the diet x breed interaction was significant (p<0.001). Averaged over all levels, on BCS:C diets there was no significant difference in TOMI between the breeds although it tended to be higher  with N'Dama at lower levels of supplementation (Figure 1) ; on groundnut hay based diets (GNH:C and GNH:M),  crossbred had higher TOMI although the difference was not significant with GNH:C at 0% and 10% level of supplementation (Figure 1).

It should be noted that there was no refusal of supplement during the entire study, therefore the different effects observed in TOMI were driven by roughage organic matter intake.

Increasing level of supplementation increased TOMI (quadratic p< 0.05) with both breed and all the diets, although there was a sudden increase with groundnut hay at 40% level of concentrate supplementation. The optimum levels estimated with the single slope broken line model depended on the diet and on the breed. For instance the optimum level was estimated for the two breeds at 10% and 20% with BCS:C and GNH:C respectively while with GNH:M it was estimated at 30% and 10% for N’Dama and crossbred respectively.

Averaged of all data, the digestible organic matter intake (DOMI g/kg^.75d^-1) was neither affected by the breed nor by the diet fed to animal (Table 4). However, there was a significant breed x diet interaction. On BCS:C, N’Dama consumed 8 g/kg^.75d^-1  digestible organic matter more than crossbred (61 and 53 g/kg^.75d^-1 respectively). On groundnut hay based diet crossbred had the advantage, the DOMI was with GNH:C 55 and 59 g/kg^.75d^-1 and with GNH:M 54 and 59 g/kg^.75d^-1 for N’Dama and crossbred respectively.

Increasing level of supplementation quadratically increased DOMI of BCS:C in both breeds (table 5) and the optimum level of supplementation for DMOI was estimated at 9% for the two breeds.

With GNH:C, increasing level of supplementation linearly increased DMOI in crossbred whereas it quadratically increased in N’Dama with an optimum estimated at 6% on GNH:M diet, increasing level of supplementation quadratically increased DOMI in the two breeds with the optimum level estimated at 20 and 16% for N’Dama and crossbred respectively.

Organic matter digestibility

As shown in Table 4 organic matter digestibility (OMD) was highly affected by the breed of animal and the diet fed. OMD was about 4% higher with N’Dama compared to crossbred and 4% lower with BCS:C compared to other diets. Like with TOMI there was no difference in OMD between concentrate mixture and moringa meal supplementation on groundnut hay. The interaction Breed x diet was significant; on average the difference between the two breeds in advantage of N’Dama was higher with BCS:C (7%) compared to  groundnut hay diets (2.8 and 2.1% with concentrate and moringa supplementation respectively). The diet x level interaction on OMD was only significant at p<0.01(Figure 2); on baby corn based diet, N’Dama digested more than their crossbred counterparts irrespective of the level of supplementation, while when groundnut hay was fed with either concentrate or moringa meal as supplement, the difference in favour of N’Dama was only significant at low level of supplementation (less than 20 and 30% with concentrate and moringa supplementation respectively).

After these levels the difference between the breeds was not significant although the crossbred tended to have an advantage (Figure 2). Increasing level of concentrate supplementation did not affect the OMD in both breeds fed baby corn based diets. However when animals were fed groundnut hay, on one hand increasing level of concentrate supplementation did not affect OMD in N’Dama whereas it significantly increased (quadratic: p< 0.001) in crossbred with a peak 20% (Figure 2). On the other hand, with moringa supplementation there was a quadratic increase in OMD with a peak at 20% in N’Dama and at 30% in crossbred.

The digestibility of neutral detergent fibre (DNDF table 4) showed the same trend with regard to breed difference but this difference was more pronounced and ranged from 10% with BCS:C to 5 % with groundnut hay diets in advantage of N’Dama;  DNDF was higher with BCS:C compared to groundnut hay diet and was very low with GNH:M.

The Diet x Level interaction was also highly significant (Figure 3).

When animals were fed baby corn stovers as basal diet, NDF digestibility was significantly higher in N’Dama compared to crossbred at all level of supplementation. On groundnut hay based diets the difference (advantage of N’Dama) in NDF digestibility was only significant at level of supplementation less or equal to 10% with concentrate supplementation and to 20% with moringa supplementation (Figure 3).

Increasing level of concentrate supplementation did not significantly affect NDF digestibility of BCS:C and GNH:C in the two breeds (Figure 3). Nevertheless with GNH:C it tended to reach a peak at a level of 30% in crossbred and 10% in N’Dama. On the other hand graded levels of moringa supplementation linearly increased NDF digestibility in both breeds.

Daily weight gain and efficiency of feed conversion

There was no effect of breed on average daily weight gain expressed in g/kg^0.75.  The overall effect of diet was not significant (Table 4) however, the between diets comparison showed that animals gained significantly (p<0.05) more weight when they were fed BCS:C compared to GNH:C and GNH:M and there was no significance difference between the later diets. There was a significant Diet x level interaction. With groundnut hay diets there was no effect of level of supplementation on ADG (Figure 4), while with BCS:C a quadratic (p<0.01)  trend was observed with increasing level of supplementation on ADG with the two breeds.

There was no significant difference between the breeds in efficiency of feed conversion (EFC table 3) when data were averaged for all the diets. Within the diets animals were significantly more efficient when they were fed BCS:C. On the other hand, animals seemed more efficient on GNH:M compared to GNH:C.

However, there was a significant Breed x diet interaction where crossbred were more efficient on BCS:C (9 against 14 for N’Dama) and on groundnut hay based diets, N’Dama surpassed the crossbred  with ratios of 11 vs. 13 for GNH:C and 9 vs. 27 for GNH:M.

Discussions and conclusions

Feed intake as affected by the cattle breed

Breeds of ruminants with high milk production or growth potential generally have greater maintenance energy requirements (ME required for energy stasis; fasting heat production plus heat increment) than those with lower potential (Ferrell and Jenkins 1987; Frisch and Vercoe 1991; Goetsch 1998; Goetsch and Johnson 1999). It has also been generalized that high production potential of some breeds is expressed only with no stressful nutritional environments and high quality diets. High quality diets elicit high peripheral tissue energy availability relative to absorbed energy, which with high capacity for peripheral tissue energy accretion or secretion in milk apparently allows a level of intake more than compensatory for high maintenance energy demand. High splanchnic bed energy use relative to digestible energy (DE) intake with low quality diets corresponds to a low quantity of energy used by extra-splanchnic tissues and with high production potential a high proportion of this energy is devoted for maintenance. Thus digestible OM intake per kg BW^0.75 with very low quality forage based diets would be greater for biological types with low vs. high production potential and as forage quality increases feed intake and energy accretion or secretion in milk should change more for biological types with high potential.

In accordance with aforementioned rationale, in the present study there was a significant breed x forage interaction. Crossbred had higher OM and DOM intake per kg BW^0.75 compared to N’Dama when animals were fed groundnut hay based diets while baby corn stovers based diets N’Dama had the highest. These observations are in accordance with the results of Goetsch and Johnson (1999), they reported a forage x breed interaction when comparing four breed groups of sheep. During our study animals consumed the entire supplement offered and the difference observed in total organic matter intake was driven by the difference in roughage (basal) organic matter intake.

Effect of cattle breed on in vivo digestibility

In the literature, few digestion experiments have been devoted to between-breed comparisons in cattle. In the present study there was a significant difference in OM and NDF digestibility between the two breeds and this difference was highly dependent on the diet (roughage: supplement) and the level of supplementation. When the diets consisted of a cereal stovers as basal, dry matter OM and fibre digestibility were higher in the local breed whatever the level of supplementation while on groundnut hay based diets the local breed was superior only at low level of supplementation.  Such between breed differences are in contrast with the observations of Doreau and Diawara (2002),  Xue and Han (1997), Kennedy (1982/95), Grimaud et al (1998) who compared either two breeds of Bos taurus (Charolaise vs. Holstein) or bovine genotypes more different (Bos taurus vs. yaks (Bos grunniens), Bos taurus vs. swamp buffaloes (Bubalus bubalis), Bos taurus vs. Bos indicus)

However, between-breed differences have been mentioned in the literature in cattle (Norton et al 1979) but it corresponded to a better sparing of N in breeds adapted to their environment than in exotic breeds or to the difference in the anatomy where Bos indicus have been reported to have smaller digestive tracts (Schneider and Flatt 1975) and faster passage rates of digesta (Preston and Leng 1987) than Bos taurus breeds. The crossbred animals used in this study were between 5-6 years old and could be assume to be as well adapted to the environment as the local breed. With the current stage of molecular techniques, comparison of rumen microbial community between breeds of ruminants related to fibre digestibility is highly suggested as an entry point to understand or explain differences in digestibility.

Feed intake and digestibility as affected by the level of supplementation

A supplement should primarily provide critical nutrients lacking in the basal diet and create an environment conducive to optimize the release and utilization of other nutrients in the basal diet (Ngwa et al 2002). Numerous reviews have discussed the responses of growing cattle fed low quality roughage and it appears from these reviews that the responses to supplementation depend on the type and level of the supplement and the quality of the basal; the results of the study are in agreement with the previous observations.

In the present study with groundnut hay as basal diet, increasing level of concentrate supplementation did not significantly change total decreased intake of groundnut hay as basal while the total intake did not change significantly although the greatest total intake was observed at 10% and the lowest at 30% compared to the non-supplemented groups. Allden (1981) and Sanson (1993) reported that increases in intake due to protein based concentrate are not consistent when forages contain more than 7% CP. The groundnut hay used in the present study had 14.4 % CP (Table 1). When basal diet consisted of baby corn (6%CP), intake of the roughage increased at the first level of supplementation (10%) then decreased with subsequent levels.  The total organic matter intake followed the same trend and the optimum intake estimated at 10% level of supplementation in both breed. Decline in roughage and total intake with high level of supplementation (40%) agrees with other studies. Concentrate at low level acts as a true supplement and improve forage utilization.

Organic matter and NDF digestibility were not affected by concentrate supplementation of either baby corn stovers or groundnut hay. These feeds contained 6 and 12 % CP (Table 1) necessary for optimal rumen fermentation.

In general crossbred gained more weight and the feed conversion efficiency averaged for all the levels was better with N’Dama compared to crossbred only on groundnut hay based diets. These results suggested that on low quality roughage native breeds would used proportionally more of their energy intake for maintenance (McDonald et al 1995) and exotic breeds will consume more feed relative to their maintenance energy requirements, thereby gaining faster and more efficiently (Krehbiel et al. 2000). Therefore, with feed of better quality however, native breeds might economically be suitable for fattening purposes.

Moringa oleifera as an alternative supplement for cattle production

Moringa meal was included in the study to be assessed as an alternative supplement to cattle production. Little information on the use of moringa leave as sole supplement to ruminant production exists in the available literature. In our study the optimum level of supplementation was around 20% which agrees with Aregheore (2002). He used moringa as a supplement to batiki grass (CP=8.3%) in growing sheep and observed highest intake and digestibility at levels of supplementation between 20 and 30%,. Groundnut hay as a basal diet could not yield any animal response in terms of weight gain however the linear increase observed with NDF digestibility suggested high microbial activity in the rumen. Moreover at 40% inclusion no negative effect was observed on animals as it was the case in Aregheore (2002) where animals were fed diet containing up to 80% moringa.

Groundnut hay is widely used in other parts of West Africa as a supplement to low quality cereal straw. But in the Gambian context or in southern Senegal where groundnut is the main cash crop, groundnut hay constitutes the main basal diet for ruminants and non-ruminant herbivore livestock. Supplementation of this roughage with concentrate mixture is common practice in ruminant production in the region. Although in our study supplementation did not affect ADG, in other production level (e.g. dairy) where protein and energy requirements are higher groundnut might need to be supplemented. In this line previous study with milking crossbred and local cows (Nouala et al 2003) revealed that supplementation of groundnut hay with concentrate mixture substantially increased milk off-take and reduced weight loss during lactation in the two genotypes; therefore the most promising combinations obtained in our study should be tested on dairy cow.

Acknowledgements 

This work was funded by Projet de Recherche et développement pour l’Elevage en Afrique de l’Ouest (PROCORDEL) based at the International Trypanotolerance Centre(ITC).

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Received 8 November 2008; Accepted 16 July 2009; Published 1 October 2009

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