A survey on calf feeding systems, problems and improvement options available for the smallholder dairy farmers of Turiani in Tanzania

H L N Lyimo,  L A Mtenga, A E Kimambo, T Hvelplund*, G H Laswai and M R Weisbjerg*

Sokoine University of Agriculture, PO Box 3004, Morogoro, Tanzania.
hlnlyimo@yahoo.com
^* Danish Institute of Agricultural Sciences, Research Centre Foulum,
PO Box 50, DK-8830, Tjele, Denmark.

Abstract

Sixty smallholder Dairy Farmers (SHDF) were interviewed using structured questionnaire and 8 group meetings were held in eight different villages in Turiani, Mvomero District to characterise the existing calf feeding systems and identify obstacles and opportunities that exist for better calf performance. Scores from 1 to 10 were used as means of valuating forage availability, calf rearing problems and available options for improvement. A score of 1 point meant least significant/valued while 10 points was the most preferred/valued option.

The survey revealed that about 97% of the SHDFs' in the area practiced the restricted suckling method, as a rearing system for their calves and it was the most preferred method. After 4 to 6 days of colostrum feeding, 40% of the farmers interviewed allowed their calves to suck residual milk alone while 57% left a teat partially un-milked for the calf to suck after milking. Calves were allowed to suck for a few seconds before milking and 30 to 60 minutes after milking by 63%. Little concentrate, less than 0.5 kg per day, was offered to calves pre-weaning by 92% of the farmers. Slightly higher amounts (0.5 to 2.0 kg/day) of concentrate were offered to calves post-weaning by 74% of the respondents. Forage from natural pastures formed the basal ration of the calves after weaning but there was no discrimination between calves and adult animals, resulting in low intakes by calves. Forage availability was found not to pose a big problem (average score of 8) but selection as to what type to feed to calves was rarely practiced. Estimated calf weights from heart girth measurements during the farm visits were 33 kg in the first month and 60 kg in the fourth month. Calf rearing problems given by the farmers in priority order included labour demand, poor growth and calf diseases. Others were inadequate knowledge on calf rearing and mortality.

Suggested improvement options were strategic feeding, emphasis on supervision and management, use of cheap concentrate and farmers' training. Others were: appropriate calf housing, allocation of sufficient financial resource to calf rearing and acceptance of technical advice. It was concluded that a proper calf feeding for SHDFs' in Turiani should include ensuring enough milk for the young calf, provide nutritionally adequate concentrate and feeding selected forages starting early in life to allow early weaning and milk saving.

Key words: Calves, rearing, restricted suckling, smallholders

Introduction

Most of the Smallholder Dairy Farmers (SHDFs') in Tanzania practice restricted suckling as a calf rearing system and the amount of milk available to the calf is therefore determined by the quantity of milk remaining after milking. It is possible that residual milk is inadequate to meet the requirement of the calves. At the early age, a good strategy focuses on optimising rumen development, fast growth and minimal stress and diseases. This can be achieved by proper feeding of the calf with sufficient milk, 3 to 4 litres/day depending on body weight (Mathewman 1993) and introduction of good quality concentrate early in life (Roy 1980). Feeding good quality concentrate is a good option to increase the total amount of nutrients available to the calf. However, the use of concentrates to feed calves by  smallholder dairy farmers is regarded as an expensive non-profitable exercise although known to promote early weaning enabling some milk savings (Ørskov and Ryle 1990). The reluctance to give concentrate to calves is due to lack of knowledge on the proper use of locally available resources, poor and limited supply of commercial calf feeds as well as high costs of some ingredients. Concentrates formulated from locally available feedstuffs would probably be cheap and a good alternative to milk.

Most farmers leave their calves to depend on forages alone after weaning and this results in low growth rate as most of the available natural forages mature early with low digestibility at maturity (Mero and Uden 1998). Selection of forages to feed in a particular season together with concentrate supplements is therefore important for good performance (Bwire and Wiktorsson 2002). This will ensure high intakes and thus sufficient consumption of nutrients by the calves. It will also reduce the workload of cutting and carrying forage to the stalls which will eventually remain uneaten by the animals creating a manure disposal problem.

Situation analysis in the SHDF is often a starting point for programmes and projects supporting intervention to improve dairying. Development of an appropriate feeding strategy for calves requires farmer's participation and trials to be conducted on their farms (Haverkont et al 1998; Cryseels et al 1986). Besides scientific requirements, the intervention sought should consider:  farmer's interests, knowledge and socio-economic status together with available feed resources. Such information, combined with scientific requirements can be used to develop proper feeding strategies to improve the calf performance. In this case, farmers' involvement through Participatory Rural Appraisal (PRA) is necessary in identifying the principle practices. PRA encourages the participation of the farmers, integration of gender, cultural and environmental aspects.

This study was conducted with the aim of describing the existing calf rearing system and identifying and ranking calf feeding problems and possible improvement options for small-scale dairy farmers in Mvomero District, taking Turiani as a case study.

Methodology

Description of the area

Turiani is one among the five divisions of Mvomero District in Morogoro Region, which lies within 37 - 38° longitude East of Greenwich, and 5 - 7° latitude south of the Equator. The altitude ranges from 380 to 520 m above sea level with annual rainfall of 1500 to 2000 mm and mean temperatures of 15-29° C. It is therefore within the humid to sub humid zone. The land is plain surrounded by the Nguru Mountains and the uncultivated lowlands are covered with grassland dominated with Panicum species, shrubs and some leguminous plants.

Surveys

A formal survey was conducted using a structured questionnaire. Sixty randomly selected smallholder dairy farmers in the division were interviewed. Sampling frame was all farmers in the ward that had kept dairy animals for more than 2 years. Information collected from this survey included general information on the SHDFs and performance, and milk and concentrate feeding of the calves. An informal survey through PRA was conducted in eight randomly selected villages within the ward. In each village, 10 farmers were randomly selected to form a contact group. Collected information from the informal survey was on available feed resources, concentrates and forage feeding to calves during pre- and post-weaning periods, forage availability and calf feeding problems and improvement options. Assessments in all group meetings were done using scoring techniques. Score range was from 1 to 10. Farmers were asked to agree on available calf feed resources, reasons for feeding little or no concentrates and not selecting forages to feed their calves and then scoring followed by assigning points. Ten points were allotted to the most considered reasons scaling down to 1 for least considered. A similar procedure was followed for the feeding problems and opportunities for improvement. In developing a calendar of feed availability and determining factors, the most important forage species were agreed on first. Following that, points (scores) were given for forage availability for each month through out the year. Finally the resulting overall feed availability was assessed. In both surveys, farmers were visited and group meetings were made after prior appointments and they were made familiar with the objectives of the research.

Farm visits were done to 38 randomly selected farmers that had a calf aged from 1 day to 9 months during the visiting time. Visits were done at the project site to verify, sort and quantify the types and amounts of feeds offered to animals. During these visits, heart girths of calves from 1 to 9 months were measured to estimate growth rates using the formula adopted from Msangi et al (1999) (ie: Body weight [kg] = 1.6*Heart girth[cm] - 81.6). Forages brought to the stall were sorted and weighed by species to establish proportions mixed by farmers to form daily rations given to the animals. Milk from the teats left for the calf to suck (calf teat) was milked out and measured to obtain the amount the calf could get. Dam production was also recorded and later used to estimate the amount of residue milk sucked by calves taken as 20% of dams' production (Mai Van Sahn et al 1997; Ugarte 1977).

Data analysis

Descriptive statistical analyses of the data and means comparisons were conducted using the SPSS 2000 programme.
 

Results and Discussion

General observations

The area experiences five distinct seasons of the year, which are long and short rains (from mid February to May and November to December), and the long and short dry period (from August to October and mid January to mid February). The fifth season is the dry cool period that is from June to July. The area has good fertile soils suitable for crop production. Due to the favourable climate, the forage availability was not found as a big constraint to calf feeding. The good climate also means high returns from both crops and dairying; however, this appeared to affect the dairy enterprise negatively as more of the resources were channelled to crop production. This is a tendency found among many SHDF in the country and elsewhere (Mussa 1998; Abate et al 1985). Panicum species and mixtures of leguminous plants dominated the lowlands and uncultivated marginal lands of the division. Napier grass was found in the riverbanks and roadsides. Ipomoea spp were found in the swampy areas. Notorious weeds in sugar plantations and other crop fields were itch grass and Cynodon plectostchus, which formed a good forage source. In such cases feed un-availability in terms of quantity was negligible. Nevertheless, in terms of quality it might be a problem due to the seasonal effect (Bwire and Wiktorsson 2002; Temi 1999). These forages need to be fed selectively and supplemented with concentrates as all these forages mature early with deteriorating nutritive value (Mero and Uden 1998; Bwire and Wiktorsson 2002).

Livestock production

Registration of livestock numbers was problematic because neither the division nor the ward offices kept proper records on this. It was estimated that there were 1063 cattle for milk purposes kept permanently in the division. In addition to dairy cattle, 8% of the respondents also kept local zebu animals.  Average herd size for dairy farmers interviewed was 3 animals. This could be the economical size given that all farmers took dairying as a component in the farming system or part time enterprise. Farmers were more involved in crop production which engaged 34% of their total available family labour (Figure1). Cattle population data indicate that the area is not traditionally one for livestock keeping (Planning Commission/RC Morogoro 1997). However the cattle population growth rate is high as a result of government efforts and NGO dairy programmes. The most common breed kept was Friesian crossbreed followed by Ayrshire crosses possibly because of their superior performances over other crosses (Shekimweri 1984; Adeneye 1982) or because of their availability in the country.

Figure 1. Labour use by Turiani smallholder dairy farmers

Calf performance (growth and mortality)

It was difficult to quantify the mortality and growth rate of the calves in the villages because of a general lack of records kept by the farmers and the ward extension officers. However, most of the farmers interviewed, and discussions with the key persons, indicated that calf survival and growth rates were low. Estimated calf weights from the farm visit measurements were 33 kg at the first month and 60 kg at the fourth month. These are normal weights in the SHDFs of Tanzania and other tropical countries (Mandibaya et al 2000; Mulangila et al 1997; Topps 1994). However, they indicate a growth rate of 0.1 kg/day which is very low. At six months, estimated weight was 95.6 kg which is lower than 109 kg reported by Mai Van Sanh (1997) for crossbred calves reared under restricted suckling. This low growth performance could be attributed to the poor nutrition and the sub optimal management practices observed in most visits. If this situation is improved, growth and survival could also be improved (Mathewman 1993; Payne 1990).

Calf feeding systems

Restricted suckling was the system found to be practiced by almost all farmers (97%) in Turiani. Milking was done twice a day in the mornings and evenings and the calf was allowed to suck for a few seconds before milking and for some 30 to 60 minutes after milking (Table 1). This period as reported by Little et al (1989) is sufficient for the calf to obtain all the milk left including the residual milk. It was reported that restricted suckling was practiced as a means of stimulating milk let down. This is in line with what was reported by Ugarte and Preston (1973) and Little et al (1989) that restricted suckling is more beneficial to smallholder dairy farmers than artificial rearing. Some 56.7% of the respondents were leaving one hindquarter un-milked or partially milked for the calf to suckle together with the residual milk (Figure 2).This was important to ensure that the calf had obtained enough milk (Mandibaya et al 2002).

Figure 2: Percentage of farmers practicing different milk feeding systems in Turiani

The majority of the farmers (57%) were allowing more than 4 days  for the newborn calf to stay with its dam all the day. In this way, it was expected that the calf  would be able to get enough colostrum, which is important to optimise passive immunity in the calves. Some farmers (33.3%) allowed more than 7 days, which was seen as a good practice of ensuring enough milk to the calves in the early days where the dam production was low and fast growth was needed in the calf. However, where the dam production is higher than the calf needs, this practice could lead to calf scouring and mastitis in the dam (Boe and Havrevoll 1988; Mathewman  1993). The results are economic loss through having no or little milk for sale and the negative effect on milk secretion (Ugarte and Preston 1973).

It was observed that concentrate and hay were introduced and accepted by the calf during the 4^th week of life. This is later than the age often proposed in many studies (Matthewman 1993; Roy 1980). Probably, this was due to unavailability of good quality calf concentrate to feed the calves. In early life, calves cannot utilize high fibre feeds efficiently (Otterby and Linn 1981) but feeding good quality concentrate early in life enhances the nutrient supply to the calf and is necessary for early weaning. (Berhane 1998; Plaza et al 1990). A larger group of the respondents (48%) fed the calves small amounts of concentrate (less than 0.5 kg/day), whereas 17% did not offer concentrate and the rest offered larger amounts (Figure 3).

Figure 3. Percentage of respondents feeding different quantities (kg/day) of concentrates during the pre-weaning period

Some farmers considered that there was no point in offering higher levels of concentrates pre-weaning as the calves has little capacity to eat concentrates during this period. Such observations could have been due to the poor quality of concentrate mixtures that were fed. Intake is a factor of digestibility, palatability and nutrient content (McDonald et al 1995). According to Quigley (2001), calves of the larger breeds can consume up to 1.5 kg/day of concentrates while those of small breeds can consume up to 0.5 kg/day at time of weaning of 9 to 12 weeks.

Calves were gradually weaned at an age of 4 - 6 months of age. The farmers considered that late weaning was a way to reduce nutritional stress and was necessary for stimulating milk let down before hand milking.

Farmers were aware of the importance of feeding concentrate post-weaning and they were mixing mainly maize bran, sunflower cake and common salt in various proportions.  Sometimes, maize bran was fed alone as the concentrate. The proportions of the ingredients and the quantities offered seemed to be a matter of availability and resource allocation rather than a need to supply quality feed to the animal. It is doubtful if the theoretical requirements of  9.0 to 12.6 ME/kg DM and 130 to 160 g crude protein/kg DM in calf concentrates (Roy 1980) were adequately met by such mixtures. Nevertheless, the growing animal was not regarded as important as the lactating cow and either little or none was fed (Table 3). Concentrate was reduced as the farmers felt that the calf could better adapt to intake of forage.

Figure 4. Percentage of farmers feeding different quantities of concentrate during the post-weaning period
(Above 2 kg/day concentrate was fed only when the calf was female)

The SHDFs' in Turiani depend on cut and carry forage from a common feed resource base. This is different from what was observed in other areas where farmers utilised crop residues and fodder crops substantially (Mussa 1998; Tembani et al 1994; Topps 1994). With increase in population and better income and ready market for crops, more of the uncultivated land is turned into crop fields reducing the common feed resource base. Forage selection and concentrate feeding was the most valued strategy (score of 9) but less than 20% were practicing it (Table 1). Little or no selection was made to supply the calf with more nutritive forage despite of its importance being well known to farmers. This could be due to lack of interest of hired labour and that some farmers considered this exercise as cumbersome, laborious and costly without taking into account the importance of fast growth and development of the calf. Forages and concentrate were not introduced to the calves until the 4^th week of age, although it is known that earlier introduction of forages to calves is necessary to stimulate rumen development and digestive enzyme activities (Lane et al 2000; Thichet 1988). The calves were stall-fed and therefore were denied the chance to select what to eat. Lack of opportunity to select forages  can lead to low intake and hence contribute to poor utilization of milk and concentrate.

Reasons given for not feeding concentrate and not selecting forages (Tables 2 and 3) indicate that farmers need to be made more aware of the importance of supplying a balanced ration to the growing animal. It appeared that farmers do not consider fast growth as an important factor in the production cycle.

Forage availability

It appeared that forages were available almost throughout the year in all villages (Figure 5).  Four factors including season of the year, labour constraint, distance to the cutting sites and easiness to cut and carry were identified as the major constraints to availability.

The most available forages included Panicum, Penniseteum, Commelina, Ipomea spp., Cynodon plectstachus, Rottaboellia and legumes of several species (Appendix 1). When availability scores were plotted over the five seasons in a year (Figure 6), it can be seen that particular species of forages are more available at certain periods of the year. These forages have an average crude protein content in DM of 16.3 % for the legume mixtures and 7.5% for the grasses that varied with season (Temi 1999). This implies that a feeding strategy should focus on specific forages combinations at a specific season of the year. When combined, they would form a better diet than when fed as single species. Negligible numbers of farmers had cultivated improved pastures and fodder trees, which could not be considered to be providing any substantial contribution to the feeds available. One reason for this is the land scarcity as expressed by most of the farmers (94%).

Figure 5.  Farmers assessment of forage availability over the year by village

Figure 6.  Farmers assessment on the overall forage availability by species

Calf feeding problems and improvement options as expressed by farmers

A participatory way of establishing the obstacles and opportunities for development (Table 4) were used in the study to avoid the one way transfer of technology described by Chambers and Juggins (1987).  Similar to findings in other SHDF communities (Myoya 1991; Abate et al 1985), labour was considered as the most serious constraint to dairy production . The farmers' households had available an average of 39 person-hours per day, of which 28% was used in non-specific activities. It can be concluded that this constraint is being exaggerated by poor labour budgets and lack of adequate knowledge, which is also ranked as a constraint (Table 5). Likewise most equipments/tools used in farm works were rudimental (outdated technology) which does not give high efficiency and required a lot of energy and time for a single activity.

After some discussions and clarification on the consequences of poor feeding, it was realised that most of the mentioned problems are nutritional oriented. Strategic feeding of milk, concentrate and forage to calves was seen as most important (Table 5). Other solutions include additional training to the farmers, more supervision by the farmers and practicing more proper husbandry to the calves by accepting technical advice. The need to realise the importance of calf rearing and to allocate adequate funds to it was also seen as a way to improve calf performance.

Conclusions

The present study has revealed several aspects that indicate poor feeding as a major problem to the SHDFs' in the Turiana area. Although the majority of farmers had declared they left a teat, completely or partially un-milked,  for the calf, only a few were seen to be doing this when visited.

It appeared that the farmers always tried to save more milk for home consumption or for sale at the calf's expense.

Little and poor quality concentrate was fed to the calves with unselected forages.

From the list of constraints and improvements developed and ranked by the farmers, lack of an appropriate feeding strategy for the calves appeared to the major factor limiting calf performance.

Acknowledgement

The financial support given by the ENRECA-ASLIP project at Sokoine University of Agriculture is highly acknowledged.

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Appendix 1: Forage availability calendar

	Jan	Feb	Mar	April	May	June	July	Aug	Sep	Oct	Nov	Dec	Mean
Panicum	8.50	8.63	8.88	9.13	9.38	8.63	8.13	7.50	6.88	6.88	7.63	8.38	8.21±0.62
Panisetum	7.88	7.88	8.00	8.13	8.13	7.88	7.13	6.50	6.13	6.25	7.13	7.75	7.40±0.59
Rottboellia	8.00	6.25	6.88	6.50	3.75	1.00	0.00	0.00	0.00	1.13	3.38	5.63	3.54±2.42
Ipomea ssp.	3.13	3.00	3.00	3.88	4.38	5.38	5.25	5.00	4.00	3.63	3.50	3.25	3.95±0.66
Commelina	6.00	6.00	6.38	6.50	6.25	6.13	5.13	4.88	4.63	4.50	5.00	5.63	5.58±0.58
C.plectostahus	5.25	5.13	6.13	6.38	6.50	5.75	4.63	4.38	3.63	3.75	4.38	5.00	5.07±0.72
Legume	5.13	5.13	5.75	6.00	5.50	4.75	3.88	2.63	2.13	2.13	3.25	3.75	4.17±1.12
Maize strover	1.00	3.25	1.63	0.38	2.63	2.88	0.75	0.00	0.00	0.00	0.00	0.00	1.04±0.96
Gliricidia	0.25	0.38	0.75	0.38	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.25	0.31±0.09
Overall	8.63	8.75	9.63	9.75	9.38	8.75	7.50	6.88	6.25	6.63	7.38	4.40	7.77±1.63