Udder health in organic dairy cattle in Northern Spain

Abstract

This paper presents first data on the udder health status of organic dairy farms in Northern Spain and analyses some management and productive characteristics related to milk production comparing with the conventional sector. Five certified organic farms from the Cantabrian Region were monitored monthly from February 2006 to January 2008 and individual samples of all lactating cows were taken from parturition to the end of lactation. Although organic farms in our study showed a great individual variability, overall these were small (<50 lactating cows) traditional farms, with a high degree of pasture (66-82% dry matter intake) and a milk production (average milk yield: 5950 L) 23% lower compared with the reference conventional sector (<50 cow farms). The organic farms had higher (p<0.05) average number of calves per cow (3.93) and a lower number of first-lactation cows (16.9%) than the comparable conventional farms (2.47 calves per cow and 33.1% first-lactation cows). Organic farms showed higher (p<0.05) somatic cell counts (SCC) than the reference conventional farms (mean log 10 ±SD for all cows: 5.25±0.49 and 5.06±0.59, respectively). Detailed analysis of the SCC depending on the number of lactation and % of monthly SCC tests with linear scores indicative of udder infection suggest that while the heifers' sanitary condition at the beginning of their productive cycle was similar in both types of farms, this seems to become worse along the productive cycle in the organics. This could be related to a low use of antibiotics for prophylaxis and treatment of udder infections and merits further investigation.

Short communication: The main factors affecting somatic cell count in organic dairy farming

“…1). The SCC has been reported to increase significantly with lactation number on organic dairy farms in northern Spain, particularly farms on which antibiotic therapy is not used (Orjales et al, 2016) and has been related to chronic infection after several lactation periods (Villar & López-Alonso, 2015).…”

“…In fact without hygiene or without an adequate maintenance of milking machine, antibiotic dry therapy and teat dipping are insufficient measures to prevent mammary infections and to achieve low SCC. Recent studies in northern Spain have indicated higher SCC in organically reared herds than in conventionally reared herds (Villar & López-alonso, 2015;Orjales et al, 2016). This is mainly associated with a higher prevalence of chronic subclinical mastitis in organic herds , although the higher SCC may be partly explained by the higher number of parturitions and the lower production rates on organic farms.…”

Holstein-Friesian milk performance in organic farming in North Spain: Comparison with other systems and breeds

“…In addition to clinical and subclinical udder disease, factors like husbandry, management, genetics, and nutrition and associated metabolic and endocrine changes have some influence on the SCC. In this sense, at a hypothetical identical sanitary condition the lower milk yield and the higher mean age of lactating cows in organic farms compared with conventional farms could leave to a higher SCC in the former (Villar & López-Alonso, 2015). Differences in the udder health between organic and conventional herds are not necessarily only due to a direct effect of the organic management, and many other differences in management routines may exist between organic and conventional farms besides the "purely" organic and such differences might vary across studies (Fall et al, 2008).…”

Dynamics of mammary infections in organic dairy farms in Northern Spain

“…Organic farms in Northern Spain have higher SCCs compared with the conventional ones, which could be related to a higher incidence of mastitis (Villar & López-Alonso, 2015). However, it is also well known that other husbandry factors (Schepers et al, 1997) -mainly the higher number of lactations and the lower milk yield observed in the organic farms-could explain at least in part the higher SCC observed in the organic herd.…”

“…Overall all the farms were small (<50 cows in lactation) traditional farms, with a high degree of pasture (66-82% dry matter intake (DMI)) and a low milk production (average milk yield: 5950 L) and used homeopathic treatments to some degree. Details of the farms and sampling collection are described in Villar & López-Alonso (2015).…”