Comparing irrigated biodynamic and conventionally managed dairy farms. 2. Milk production and composition and animal health

Abstract

Ten paired irrigated dairy farms under biodynamic (BD) and conventional (CV) management were compared over a 3-year period (1991–93). The paired farms were located in the irrigation districts of northern Victoria and southern New South Wales and were matched for soil type, cattle breed and farm area. The BD farms practised BD principles for an average of 16 years before the study. The effects of farm management on milk yields and composition and animal health were examined by annually surveying farm managers regarding disease incidence and chemical treatment of animals, and by measuring milk yield and composition and faecal egg counts over the experimental period. The two hypotheses tested were that (1) milk volume and milk solids per cow would be lower under BD management, and (2) the incidence of internal parasitic infection and disease would be lower under CV management. Milk production and milk components produced, both on a per hectare and per cow basis, were 24–36% higher (P < 0.01) under CV management, due to significantly higher pasture intakes (P < 0.001). Although the incidence of parasitic infection was similar for mature cows, CV farms consistently used a greater number of chemical treatments (P < 0.05). Although BD heifer calves <8 months in age had significantly (P < 0.05) higher faecal egg counts, the results highlight the risk of reduced growth rates in calves due to high rates of parasite infection, under both management systems. Somatic cell counts were higher (P < 0.05) under BD management, with this being consistent with the use of significantly less chemical treatments under this management system. The implications of these findings for both CV and BD management for milk production and animal health are discussed.

Modification of milk resulting in low potassium and minimal electrolyte changes with minimal changes in taste

“…Potassium, sodium, and chloride analyses were carried out using electrode methods (Zannier et al ., 2002). Calcium analyses used the Arsenazo III method (Burkitt et al ., 2007). Inorganic phosphorus analyses were carried out by the molybdic-acid direct method (Burkitt et al ., 2007).…”

Biodynamic agriculture research progress and priorities

“…In addition, earthworm biomass was greater in the CON system on account of one earthworm species, where no information was given on the number of earthworms. Burkitt et al 31 also report lower milk yields on BD farms on a per hectare and per cow basis. A significantly greater number of chemical treatments per cow were used on CON farms.…”

“…Information on incidences of clinical mastitis and longevity of animals, however, is not provided. Burkitt et al 31 suggested the use of certified inputs on BD farms to increase milk fat, protein and production levels, but did not give further details. This was the only published study found that dealt with farm animals and BD farming practices; thus a serious lack of research projects/results is found and research in this area is strongly encouraged.…”

Research must use a systems agronomy approach if management of the arbuscular mycorrhizal symbiosis is to contribute to sustainable intensification

“…We recognize the importance of efficiently using inputs and not over‐supplying, but – clearly – the high‐yielding agricultural systems for sustainable intensification and global food security must involve abundant nutrient inputs if crops are to achieve maximal yields, as these entail high nutrient outputs in produce. If nutrient inputs, including phosphorus (P), are less than outputs in produce, yields will inevitably decline: abundant AMF will not maintain yields (Ryan et al ., ; Burkitt et al ., ). In Africa, where the need for improved food security is greatest (Fischer & Connor, ), addressing this relationship through increased inputs is essential (Craswell & Vlek, ).…”