3.3 Nutritional risks from livestock production and consumption
Security of intra-household nutrition is a concern raised in the literature on food security. Attention is generally given to women and children, the more vulnerable members of the poor households, because such households sometimes discriminate among its members in distributing food. Generally such discrimination may prevail under conditions of inadequate food supply and there may be specific reasons for discrimination. For example, household members performing energy-intensive tasks in certain seasons may require and be given a higher share of the limited food supply. Such discrimination usually declines and disappears when there is enough food. The problem of intra-household nutrition security is not specific to livestock production systems. However, this section reviews literature on the effects of animal products (especially milk) and the ownership of ruminant livestock on the nutritional status of children in developing countries, because of the specific nutritional benefits of food of animal origin on child growth.
Of the number of children aged 6–24 months that die each year in developing countries, 2.3 million (41%) deaths are attributed to malnutrition (Schroeder and Brown 1994). Malnutrition is a growth condition depicting some degree of functional disadvantage (Neumann and Harrison 1994). Growth retardation in children is a warning signal of increased risk of morbidity and mortality, and delay in physical and mental development (Seireg et al. 1992). Short structure in children is often attributed to genetics. It has, however, been shown that variations in preadolescence child growth are due more to differences in diet and morbidity patterns, a reflection of poverty, than to genetics. These results imply that children should be expected to grow in height in accordance with the National Center for Health Statistics (NCHS) standards (Smith et al. 1993).
The growth rates of most children in developing countries are below but parallel to the National Center for Health Statistics (NCHS) reference values. Factors that affect child growth include: parental education, household income, types of agricultural production activities, economic and agricultural policies, family size, childcare, taboo and feeding practices, diet quantity and quality, processing and storage of food, water supply, hygiene and sanitation, health services utilisation, epidemics and political upheaval (Vella et al. 1995; Grosse 1998b). An integrated intervention is therefore necessary to produce the highest impact on children’s nutritional status. Nutritional status of children is affected more by the socio-economic factors than by other factors such as health services. If the socio-economic structure does not change, as Vella et al. (1995) argue, the inequality of resource distribution will persist with the continuation of poverty that forms the basis of the nutritional problem. This section examines the impact of dairy product consumption and livestock ownership on children’s nutritional status.
Nutritional anthropometrics (body measures) parameters such as weight-for-age (W/A), height-for-age (H/A), weight-for-height (W/H), head circumference and upper mid-arm circumference for age are commonly used as bases for assessing malnutrition and evaluating the effects of dietary treatment on children. Weight, height, head circumference and upper mid-arm circumference for age are the percentages of adequacy of each of these measurements based on the respective standards for the child’s chronological age (De Gwynn and Sanjur 1974). Malnutrition is depicted in chronic and acute forms. Anthropometrics indicators for acute and chronic malnutrition are W/H and H/A standardised z-scores 2 or more deviations below reference. Weight for age (W/A) (underweight) is an intermediate measure of malnutrition that combines wasting and stunting (Grosse 1998b). Acute malnutrition or wasting denotes short-term factors such as diseases or severe food shortages. It is most frequent among children below 2 years of age (Grosse 1998b). Chronic malnutrition or stunting is more common than acute malnutrition and reflects past shortage of food intake and recurring bouts of diseases. It is common among children older than 1 year of age (Grosse 1998b).
Foods from animal origin have high energy densities and provide low bulk diets, compared to foods from non-animal origin. This makes it possible for children to obtain more calories in tolerable quantities (Sigman et al. 1991; Grosse 1998b). These foods also provide high quality protein, micronutrients and better nutrition for pregnant and breastfeeding women (Grosse 1998b).
The importance of milk consumption for child growth has been demonstrated numerous times. Several studies have shown significant positive effects of the consumption of food from animal origin on children’s nutritional status in developing countries. Seireg et al. (1992) found in urban Nicaragua that non-breastfeeding children between the ages of 2.5 and 5 years who drank cow’s milk are less than half as likely to be stunted as non-breastfeeding children of the same age who did not drink milk.
In rural Dominican Republic, milk and sausage consumption have been shown to have a significant positive association with children’s nutritional status as measured by W/A, W/H and H/A growth anthropometrics parameters (Smith et al. 1993). Similar evidence from rural Embu District in the Eastern Province of Kenya points to milk, fat and potatoes as key dietary elements in influencing the linear growth in toddlers (children aged between 18 and 30 months) (Neumann and Harrison 1994). The dietary intake of stunted and non-stunted children in Kingston, Jamaica, indicates less dairy product consumption in stunted children (Walker et al. 1990). A similar pattern has been reported in Seoul, South Korea. After adjusting for energy intake of children, animal protein intake correlated most significantly with height-for-age (Paik et al. 1992).
Findings from studies undertaken by De Gwynn and Sanjur (1974) showed animal protein intake by children from Colombia to be positive and significantly associated with height-for-age and weight-for-age. This finding is supported by research conducted among Kenyan children (Sigman et al. 1991). A similar pattern has been reported in Mexico. Controlling for morbidity, maternal education and nutritional knowledge, and socio-economic status, higher consumption of animal-origin foods (as per cent of energy or protein intakes) was associated with Mexican children being heavier and taller at 30 months (Allen et al. 1992). In Indonesia, children consuming animal-origin foods were found to be less likely to suffer from malnutrition than children on vegetarian diets (Thaha and Pudjiadi 1990).
The addition of cow’s milk to the diet of children after weaning can increase linear growth and reduce stunting in populations with low milk intake. In the Khartoum Province of Sudan, 300 children aged 6–26 months were given fortnightly take home supplement of dry skimmed milk or of local beans. Each group of children was followed for 3 to 6 months. The group receiving skimmed milk showed a significant increase in length, compared to the group receiving beans (Vaughan et al. 1991). The introduction of a school milk-feeding programme reduced the prevalence of protein-energy malnutrition—underweight, stunting and wasting of children aged 6–9 years—by half in 2 years, in Ulu Selangor, Malaysia (Chen 1989). It also increased the attendance rate of children during the study period (1985–86). Since there was no major development change in Ulu Selangor, Chen concluded that reduction in the prevalence of protein-energy malnutrition and the improvement in school attendance rate among children were due to the impact of the school milk-feeding programme. The heights of village children in rural Papua New Guinea were found to be strongly correlated with animal protein from meat and fish consumption (Smith et al. 1993).
An examination of the impact of dairy technology adoption on the nutritional status of pre-school (0–59 months) children in coastal Kenya shows consumption of dairy products to have a negative effect on stunting, i.e. children from households with improved cattle breeds were found to be taller than those from households without improved breeds (Nicholson et al. 1998). Dairy technologies reduced chronic malnutrition in Kenyan pre-school children. The same study, however, indicated that dairy technology did not have a significant impact on wasting (acute malnutrition), suggesting that solutions to reduce acute malnutrition in the coast of Kenya may not be obtained only through dairy development intervention, as children do not consume milk in quantities large enough to derive the needed calories to reduce wasting (Nicholson et al. 1998).
Ownership of livestock and livestock technologies can give households more opportunities to improve the nutritional status of their children. For example, introducing ruminant livestock technologies—such as intensified dairying using crossbred cows—increases household incomes via the sale of surplus milk and dairy products. This allows households to respond in ways that favour nutritional improvements of children other than direct consumption of milk and dairy products. Higher incomes from sales of milk and dairy products may enable households to:
All these changes can strengthen the effective demand for health inputs and services and thus contribute towards improving children’s growth. In addition, when a household’s resources are increased (made possible with introduction of livestock technologies), its ability to respond to existing or new knowledge on nutritional improvements may be increased.
In a study conducted in rural coastal Ecuador, access to market foods, as measured by per capita food expenditures and ownership of livestock, mostly cows, showed the strongest correlation with children’s nutritional status (H/A, W/A and mid-arm circumference measures). Children from farm households owning livestock were less likely to be growth retarded than children of farmers without livestock (Leonard et al. 1994). One of the findings from a rural study in Nepal was that households with a milk-producing buffalo had less chance of having a severely stunted child than households without lactating buffalo (Nabarro et al. 1988, cited in Grosse 1998b).
Analysis of data from Zona Da Mata, Minas Gerais, Brazil, showed that only farm households deriving above average percentage of total income from livestock tended to have healthier children according to all three nutrition anthropometrics measures (W/A, H/A and W/H) (Vosti and Witcover 1991). The same study indicated that families who depended more heavily on off-farm employment as a source of income tended to fare worse, both in terms of caloric intake and nutritional status. The authors, however, did not observe a direct correlation between higher incomes and better nutritional status of children. Though dairy and coffee farmers registered the highest and second highest income per capita, only on dairy farms did high incomes accompany healthier children, according to W/A, W/H and H/A anthropometrics measures of nutritional status. The presence of well-nourished children in households with ruminant livestock is probably due to the availability and consumption of high quality protein and calories from dairy products.
Controlling for several indicators of economic status (e.g. occupation, land owned, years of education), Vella et al. (1995) found ownership of a cow to be the significant predictor of H/A (long-term) nutritional status in children in south-western Uganda.
Studies in rural Rwanda indicated that children between the ages of 2 and 5 years old from households with dairy animals (cattle and goats—the only form of dairy livestock in the country) were significantly taller than children from households without (Grosse 1998a). The difference in child growth was explained more by ownership of dairy animals than by household wealth, mother’s education and access to land. Controlling for other influences, Grosse (1998a) did not find ownership of non-dairy farm animals to be positively associated with child height in rural Rwanda. Since the economic value of livestock did not account for the positive association of dairy animals with child growth in rural Rwanda, Grosse (1998a) wondered whether consumption of dairy products could be the main contributing factor to child growth.
Consumption of animal products provides both nutritional benefits and dangers. Substitution of milk from ruminant animals for mother’s milk, for example, increases the risk of severe disease and death in children below the age of 6 months (Grosse 1998b). Exclusive human milk provides sufficient nutrients to children below the age of 6 months and protects them from persistent or severe diarrhoea (De Zoysa et al. 1991). Animal products are a source of bacterial food contamination and animal parasites (zoonotic infection) (Grosse 1998b). Children living in compounds where animals are kept in the absence of proper veterinary care and careful hygiene are at higher risk of animal-borne diarrhoeal diseases than other children (Pickering et al. 1986; Grosse 1998a). Studies by Pickering et al. (1986) in Bakua, a peri-urban area in The Gambia, suggest that households keeping chicken and goats are more likely to experience child death than other households. Furthermore, analysis of data from rural Kenya adds comparable information on the association of a greater risk of child mortality to the presence of ruminant animals in living areas (Gemert et al. 1984).
Summary: Livestock and child nutrition |
Ownership of ruminant livestock directly and indirectly improves the nutritional status of children in developing countries. Consumption of milk from ruminant animals by children after weaning increases linear growth and reduces stunting. Incomes from sales of milk, dairy products and animals enable households to purchase high quality non-dairy foods; improve their sanitation, environment, quality and quantities of water, thereby reducing exposure to infectious diseases; hire labour, which substitutes women’s labour input, and thus reduces their workload and gives them more time for food preparation and childcare. However, substitution of ruminant livestock milk for human milk before the age of 6 months, and the presence of ruminant animals in the living areas without proper veterinary care and good health poses serious risk of poor growth and disease to children. |
