Participatory on-farm evaluation of urea molasses mineral block as a supplement to crossbred cows for dry season feeding in rain-fed agro-ecosystem of India

A K Misra, G Subba Reddy and Y S Ramakrishna

Central Research Institute for Dryland Agriculture, Santoshnagar, Hyderabad 500 059 India
akmishra@crida.ernet.in

 

Abstract

 

An on-farm study was carried-out with lactating crossbred cows, maintained under a smallholder mixed farming system to assess the response of urea molasses mineral block (UMMB) supplementation on milk yield and cost effectiveness during the dry season. Twenty crossbred cows in early to mid lactation were selected, 10 cows were given free access to UMMB in addition to their normal ration and the other 10 cows served as control group.

 

Supplementation of UMMB licks significantly increased feed intake, milk yield and maintained live weight and body condition score of the cows. In the opinion of the participating farmers, supplementation of UMMB improved straw consumption, milk yield and general health of the animals with enhanced cash benefit of over Rs.10/ day/cow under smallholder mixed farming system.

 

The UMMB supplementation technology was found a cost-effective approach to maximizing the utilization of locally available feed resources for better animal productivity during the dry season in a rain-fed agro-eco-system of India.

Key words: crossbred cows, dry season, farmers' perceptions, milk yield, socio-economics, urea molasses mineral block licks (UMMB)

 

Introduction

 

Dairy animals are an important source of regular cash income in rain-fed agro-eco-system of India. The productivity of dairy animals is greatly constrained by the lack of green fodder and good quality feed during a prolonged dry season (Misra et al 2005). Reduction in milk production and weight losses of animals during the dry season are common features, which culminate in substantial economic losses to the farmers. The cereal crop residues such as rice straw, stovers of sorghum and maize and dry grasses are the major source of forage for livestock feeding during the dry season. These crop residues are low in nitrogen and high in crude fibre and lignin, characteristics that restrict intake and digestibility in animals (Smith 2002). These diets can not meet nutrient requirements of cows and often result in low milk production and poor health. Supplementation with the locally available concentrate is a common practice among smallholder farmers (Sharma et al 2003). Cottonseed cake as a conventional supplement is often fed to cows in lactation (Misra et al 2005). The use of urea molasses mineral blocks (UMMB) for supplementing crop residues based diet of livestock has been well documented in ruminants (Sansoucy 1995; Garg et al 1998; Singh and Singh 2003) and has the potential to increase the viability of livestock production (Leng et al 1991; Singh and Singh 2003; Misra and Reddy 2004), to increase dry season milk supplies and increase household income (Garg et al 1998; Patel 2002; Singh and Singh 2003). UMMB can be fed throughout the year but are more beneficially utilized during the dry season or when the animals are grazing low quality fodder (Bheekhee et al 2002).

 

A series of on-station trials have been conducted in India on the animal response and economic benefits of using UMMB (Srinivas and Gupta 1997; Garg et al 1998; Patel 2002; Misra and Reddy 2004). Results suggested that 30 to 40 % concentrate allowance could be reduced by feeding UMMB without any loss of animal production (Leng et al 1991; Singh and Singh 2003; Misra and Reddy 2004). However, most of the past work was done in research stations under controlled conditions and very few attempts have been made to evaluate the response of UMMB supplementation in lactating cows under semi-arid field conditions of smallholder system in the country. Though the importance of demonstrating the benefits of greater utilization of UMMB under farm conditions has been stressed in almost all the workshops, yet the numbers of papers /studies reporting on-farm UMMB research and development are few. The objective of the present study was therefore, to assess the response of UMMB supplementation on milk yield and determine the cost effectiveness of the supplement in crossbred cows maintained under small holders management conditions.

 

Materials and Methods

 

The study area

 

An on farm experiment was conducted under smallholders' management conditions during summer months (March to May 2003) at the Nazdik Singharam Village in Yacharam Mandal of Ranga Reddy District of Andhra Pradesh, India. The village was selected as per conditional criteria of Institute Village Linkage Programme, representing the agro eco-region in terms of soil, rainfall, crops and production system, with rain-fed agriculture as the main occupation. The village is situated at 17⁰20 N latitude and 78⁰44 E longitude on an altitude ranging from 550 to 600 m above MSL, 56 km South-East of Hyderabad. Geographically, the area comes under Deccan plateu. Semi-arid climate conditions prevail in the area with an average annual rainfall around 762 mm spread over 50 days in the rainy season with little precipitation during winter. The soil was Alfisols, characterized by eroded land surface, undulating topography, rugged hillocks with poor water holding capacity and multi-nutrient deficiencies.

 

Animals, treatment and feeding management

 

Twelve farmers, each having at least one crossbred cow in early to mid lactation (about 6-8 weeks after calving), were selected for the on-farm feeding trial based on their willingness to participate. This was achieved through a Participatory Rural Appraisal exercise. Average body weight of the selected cows was approximately 350 kg with an average daily milk yield of 5 kg/cow. The cows were managed by the farmers according to their farm practice. Based on the local feeding practices, body weight, milk yield, stage of lactation and parity, the animals were divided into two equal groups (10 cows/group) as Control and UMMB. The animals in the control group were fed according to the farmers' practice and those in the other group were additionally offered UMMB lick ad libitum. All the selected animals were grazed 2-3 hours daily and were fed dry and green forage together with a small amount of home-made concentrate varying from 1.0 to 3.0 kg/animal per day. The forages consisted of mixed species of grasses, sorghum stover, paddy straw and green fodder. During a preliminary feeding period of two weeks, the farmers were advised to reduce the concentrate by 25 % in the UMMB supplemented group from 2.5 kg to 2 kg/day. The UMMB was kept in front of the animals in a wooden dispenser to allow free licking and prevent biting of the blocks.

 

The UMMB, manufactured by Brindavan Phosphtes Private Limited, Bangalore, under the technical collaboration with National Dairy Development Board, Anand were purchased for the experiment. The UMMB contained fermentable nitrogen 5-8 percent, molasses 40-50 percent, mineral mixture 5-10 percent, deoiled rice bran 10-15 percent, rice polish 10-15 percent, lime 3-5 percent and oil cakes 5-10 percent. Each block weighed about 3 kg. The consumption of UMMB was monitored weekly by weighing the blocks regularly. All the animals got used to licking the blocks within an adaptation period of 2 weeks.

 

The selected animals were dewormed before the commencement of the experiment. The cows were kept in an open sided place annexed to the house of the farmers. The shed had a kachha (mud) floor and the animals had free access to water and feed. The animals were hand milked twice a day.

 

Duration, monitoring and data recording of experiment

 

The data were recorded over a period of 11 weeks after an adaptation period of two weeks. Field visits were carried out once a week to monitor the intake of feed and UMMB, milk production, milk composition and general health of the animals. The body weight of the cows was estimated at the beginning and end of the feeding trial indirectly by measuring heart girth of the cows as suggested by Sastry et al (1988) and body condition was assessed using the scale of 1 to 5 (1 poor and 5 excellent) according to the procedure designed by Braun et al (1985).

 

The participating farmers daily recorded the intake of concentrate, green and dry fodder, block and milk production on pre-designed data sheets. These sheets were checked at each visit for accuracy and consistency. Feed and fodder and milk samples were collected at fortnightly intervals and brought to the laboratory for further analysis.

 

At the end of the feeding trail, a formal topical survey and focused group discussion was conducted to know the perception of participating farmers regarding the feasibility of UMMB as strategic supplement for dry season feeding to lactating animals.

 

Analytical techniques

 

Samples of the feeds obtained during the experiment were bulked, mixed, ground and analysed for dry matter (DM), ash, crude protein (CP) and ether extract (EE) according to standard procedures of AOAC (1995). Neutral detergent fiber (NDF) and acid detergent fiber (ADF) were determined by the method of Van Soest et al (1991). Milk samples were analysed for fat, total solids, solids-not-fat (SNF), CP and ash (ISI 1961). The Digestible crude protein (DCP) and Total digestible nutrients (TDN) content of feed was estimated using the following equations reported by Van Soest (1982); Martin (1985) and Chandler (1990):

 

% DCP= 0.9 x % CP - 3.3
% TDN in straw = 96.4 - 1.15 x % ADF
% TDN in Native grasses = 105 -0.68 x % NDF
% TDN in feed supplements = 81.4 - 0.48 x % NDF

 

Statistical and economic analysis

 

The data were subjected to analysis of variance in a completely randomized design and the significance of the differences between treatment means was determined using the student t-test according to Snedecor and Cochran (1989).

 

Cost-benefit ratio was calculated to assess the economical profitability of UMMB supplementation (Amir and Knipscheer 1989) and the partial budget analysis was done to estimate the likely economic impact of supplementation technology (Stemmer et al 1998; Peso 2002).

 

Results and Discussion

 

Socio-economic characteristics of participating farmers

 

The selected farmers were from diverse social backgrounds; about 57 percent of respondents belonging to forward caste, 29 percent to backward caste and only 14 percent to scheduled caste and scheduled tribe community. The average family size of the selected households was 5.13 members per household. The age structure of households indicated that the average age of head of household was 42 years. About 55 percent of the population was in the age group of <49 years. Education plays an important role in the adoption of innovations/new technologies, and young farmers are expected to be early adopters. Education level of the head of household was low; 33 percent were illiterate, 17 percent could read and write, 23 had primary education and 27 percent had secondary education.

 

Land is an important asset of farmers, although in the case of dairy production, purchased or exchanged feed and fodder can be substituted for land holdings. The average size of land holdings was 3.92 ha. It ranged from about 0.31 ha in the case of marginal farmers to about 8.23 ha in the case of large farmers. The landless farmers were dependent on leased land for fodder production and also depended on market-purchased feeds and fodder. Nearly seven percent of landless households had taken land on lease from other farmers for growing of food and forage crops. The terms of lease were mainly a fixed amount per unit of land and varied depending on the availability of water resource and quality of the land. The majority of respondents belonged to small and medium categories; 20 percent were marginal farmers, 27 percent were small and 30 percent were medium farmers. Only 16 percent farmers were large, having more than 4 ha of land.

 

The quantity of milk production on a dairy farm did not depend on the total number of animals in the herd but was  related to the number of animals in milk. The average number of milk animals kept by farmers were 2.83, ranging from 1 to 12. The productivity of milk animals is of vital importance to livestock owners because it has a direct influence on costs and returns. The average milk production per household has a direct relationship to farm size. The area under improved fodder crops ranged from 0.09 hectare on marginal and small farmers to 0.25 hectare on large farmers, with an average of 0.16 hectare for all categories. Maize, sorghum-PC-23, hybrid napier -Co-1, guinea grass, para grass and lucerne were main fodder crops. More than 95 percent of the farmers were selling milk to dairy cooperatives.

 

Traditional feeding system

 

The cows under study were of mixed breeds, mostly Friesian and Jersey crosses with local breed. Sorghum and rice being the main cultivated crops, their stovers and straws formed the basal diet of ruminants and were fed through out the year. The productivity of these animals was mostly constrained by the lack of good quality fodder, especially during the dry season. A focused group discussion and formal topical survey showed that most of the smallholder dairy farmers had adopted the practice of supplementing their animals with a homemade concentrate in order to improve production. The major components of the concentrate were rice bran, maize, sorghum, pulse chunni (broken grains of pigeon pea/ black gram/green gram), coconut cake and cottonseed cake. Mineral mixture and common salts were occasionally provided to the animals. The farmers mixed feed ingredients and soaked them in the water for few hours before feeding to animals or in a few cases, fed as a complete diet. However, the quantities of individual feed ingredients included in the concentrate mixtures seemed to depend on their relative availability rather than on the farmer's conscious desire to supply better quality feed to their animals. The availability of feed was scarce and cost was high during the dry season and therefore animals received insufficient amounts of forage most of the time.

 

Chemical composition, nutrients intake and performance of the animals

 

The chemical composition of feed offered to experimental animals is presented in Table 1. Most of the basal roughage available for feeding during dry season was of low quality (4.0 - 5.4% CP; 63 - 77% NDF), green forages were of medium quality (> 7% CP and 25 - 34% CF), and do not meet production requirements of the animals. Fibrous crop residues and natural pastures in the dry season were of low nutritive value and were below the capacity to meet the nutritional requirement of livestock (Smith 2002).

The daily intake of UMMB ranged from 275 to 375 g and averaged 326 g/cow. This variation is understandable given the variability in lactation stage, parity, age and basal feeds provided by the different farmers. Some farmers observed that some of the animals did not lick the UMMB initially, presumably because of problems in palatability or access to sufficient green forages, particularly maize and lucerne. Such farmers sometimes used to sprinkle flour or salt on the blocks to induce licking.

 

Feeding UMMB stimulated intake of the basal diet. Supplementation of UMMB significantly (p<0.05) improved total dry-matter intake (Table 2).

Improvement in the basal diet due to UMMB supplementation has been well established and may vary widely depending on quality of basal feed and feeding system (Leng et al 1991; Garg et al 1998; Bheekhee et al 2002; Singh and Singh 2003). Most of the cows in the on-farm study had fairly good body condition scores ranging from 2.3 to 3.1. Significantly higher body weight gain (P<0.05) and body condition score (p<0.05) were recorded in animals supplemented with UMMB than for un-supplemented animals (Table 2). The average daily DM and TDN intake of UMMB cows was sufficient to meet their nutritional requirements, weighing 350 kg and yielding 5 liters milk with 4.5 % fat content (Ranjhan 1998). However, the diets of control animals were unable to meet the protein requirement, which was reflected in low milk yield.

 

The cows supplemented with UMMB produced 30 % more milk (p<0.05) than the control group (Table 3). These results confirmed the earlier reports that indicated an extra yield of 0.5-1.5 kg milk and / or saving of 20-30% concentrate with a reduction of feed wastage of 20-30% (Singh and Prasad 2002).

Another on-farm experiment conducted in Uttaranchal, India indicated that the feeding of UMMB increased milk production by about 37% in buffaloes and 34% in local cows, without any adverse affect on the body weight and health of the animals (Singh and Singh 2003). Leng et al 1991) compared the results of conventionally fed animals with those fed UMMB and by-pass protein along with decreasing quantities of concentrate and showed that after reducing the amount of concentrate by 40%, feeding of UMMB and by-pass protein maintained the milk yield and increased the farmers net income. The improvement in milk yield with UMMB feeding may be attributed to balanced energy: protein ratio, that resulted from improved rumen efficiency with optimum concentrations of ammonia in the rumen (Leng et al 1991). Quick response to UMMB supplementation was obtained when animals were fed rice straw. Supplementation of UMMB significantly (p<0.05) increased fat content of milk by about 8 % compared to control group, presumably due to high acetic acid fermentation in the rumen associated with increased digestibility of CF (Sudhakar et al 2002) and improved energy intake (Sivaiah and Mudgal 1983).

 

Economic analysis of UMMB supplementation

 

A partial budget analysis measures those items of income and expenses that change (Stemmer et al 1998). Therefore, the costs of UMMB, concentrates and dry roughages were considered since all other variable costs (grazing, green fodder and labour) were the same for both the groups. Following assumptions were made in the calculation of partial budget analysis. Cost of dry roughages and concentrate was calculated on the basis of market rate prevalent during the experimental period; i.e. @ Rs.1000/tonne for dry roughages and Rs. 6000/tonne for concentrate. Procurement price of UMMB was Rs. 37.43/block of 3 kg. Selling price of milk by the farmer during the experimental period was Rs. 9/litre.

 

Feeding of UMMB improved marginal rate of return by 644%, with a benefit: cost ratio of 6.44, which appears to be very lucrative over the traditional feeding system (Table 4). The net benefit due to supplementation with UMMB on per animals basis was Rs. 10.62/day over the traditional feeding. High returns are required from any farm innovations to offset the risks associated with its adoption (Peso 2002). World Bank experiences showed that increased earnings of 200% are needed to assure that small holders will adopt a new technology package (Donaldson 1991).

Farmers observed that besides increase in milk production, all the animals of supplemented group showed symptoms of heat at the proper time and conceived at first service. Conversely, in the un-supplemented group, one cow did not conceive even after third insemination and on average 1.7 services were needed per conception. Further, farmers did not notice the symptoms of mineral deficiency and disease occurrence in the supplemented group whereas control animals showed symptoms of mineral deficiency. In view of the above, the economic returns may be higher if the positive long-term impact of supplementing UMMB on general body condition and reproduction are also taken into account. Considering the present cost of feed supplement and the market price of milk, UMMB supplementation was found both economical and cost effective.

 

Farmers' perceptions

 

Almost all the participating farmers reported that by supplementing UMMB, cows consumed more roughage, maintained good health and productivity and these effects were sustained even after reduction of concentrate allowance during summer months when green fodder was scarce. All the farmers readily accepted the practice of using UMMB supplementation and were willing to continue in future, if these were available in the local market and milk could be sold at an assured rate of Rs.9-10/litre in the village. However, they expressed apprehension about the availability of proper quality UMMB in the local market. In situations, however, where UMMB is either sold at higher rate or where there is no assured market for milk, the farmers perceived no advantage in adopting improved practices. This issue is further complicated by the fact that small holders often have to balance the use of scarce cash for animal feeding against its use in the family or crop production in the absence of warranted credit facilities (Sharma et al 2003. Further farmers observed that the benefits of feeding UMMB were not visible immediately. It took at least two-three weeks and depended upon regular licking of the block by the animals and on feeding patterns. For effective utilization of UMMB, it is essential that the block be put in a place that is accessible to the animals so that they could easily lick the block as and when necessary (Patel 2002). Under smallholder condition, however, this was not easy to achieve because of the many reasons including farm-to-farm variation in cowshed design. In most of the cases animals were kept in front of the house in a limited area and often they were tied to a pole by a rope so that they can move around. Some farmers kept their animals in fields during the day and brought them home only in the evening for milking and night shelter. Some other farmers took their animals to graze instead of keeping them in one place for stall-feeding. In such situations, it was difficult for the farmers to find an appropriate place for UMMB feeding.

 

Conclusions and implications

• The results obtained in the present study showed a positive effect of UMMB supplementation on the feed intake and milk production. Supplementation of UMMB to animals fed low quality fodder during summer months may be an appropriate alternative to other supplements (commercial feed) especially when these are short in supply and get expensive. UMMB feeding also demonstrated the potential of increasing viability of livestock production, increasing dry season milk supplies and enhancing household income, particularly during droughts.
  
  
• Nonetheless, it must be mentioned that there is a need for long-term studies on the response to UMMB supplementation on animals' performance under smallholder condition in dry lands that may yield information beyond the short-term responses observed in the present study. Further, it is also important to state that under participatory on-farm research, it is difficult to control rigid experiments according to strict analytical procedures. It is more important to obtain experimental results, which are useful to the farmers in terms of improving their resources and livelihood.
  
  
• The present findings demonstrated that UMMB technology is a cost-effective approach to maximizing the utilization of locally available feed resources for better animal productivity during the dry season and may perhaps constitute an innovative feeding strategy for other species of livestock as well, where concentrate feeding is not a common feature, particularly in rearing of small ruminants in rain-fed agro-eco-systems of India.

 

Acknowledgement

 

The authors are thankful to the Director, CRIDA, Hyderabad for providing facilities to conduct the on-farm research; and are grateful to the farmers and project staff for their active participation in the research programme. The financial assistance from National Agricultural Technology Project, Indian Council of Agricultural Research, New Delhi is duly acknowledged.

 

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