Economic evaluation and efficacy of strategic-selective treatment of gastrointestinal parasites in dairy calves.

In the Experimental Farm of the Universidade Federal de Lavras (EF-UFLA), state of Minas Gerais, Brazil, on their day of birth, female Holstein calves were randomly selected and placed into two groups containing fifteen animals each: Strategic-Selective Treatment (S-ST) or Conventional Treatment (CT). In the S-ST, calves were treated after coproparasitological examinations according to criteria established previously by the researchers. Calves in the CT were treated according to the opinion of the veterinarian of EF-UFLA. For statistical analysis, the frequency (%) of fecal samples with count of eggs per gram of feces (EPG) ≥300, count of oocysts per gram of feces (OoPG) ≥500 and fecal samples with count of cysts of Giardia spp. ≥1 were conducted. The overall average frequency of fecal samples with EPG ≥300, OoPG ≥500 and Giardia spp. cysts ≥1, respectively, was similar (p >0.05) between S-ST (20.3%; 17.3%; and 31.5%) and CT (26.4%; 23.9%; and 37.3%). The effective operational cost, per animal, in 12 months, was of R$ 784.58 (US$ 241.41) and R$ 83.90 (US$ 25.81) in S-ST and CT, respectively. The S-ST requires adjustments to be used as a technically efficient and economically viable alternative for the control of gastrointestinal parasitosis in female Holstein calves.

Economic evaluation and efficacy of strategic-selective treatment of gastrointestinal parasites in dairy calves / Avaliação econômica e eficácia do tratamento estratégico-seletivo de parasitos gastrointestinais em bezerras leiteiras

Abstract In the Experimental Farm of the Universidade Federal de Lavras (EF-UFLA), state of Minas Gerais, Brazil, on their day of birth, female Holstein calves were randomly selected and placed into two groups containing fifteen animals each: Strategic-Selective Treatment (S-ST) or Conventional Treatment (CT). In the S-ST, calves were treated after coproparasitological examinations according to criteria established previously by the researchers. Calves in the CT were treated according to the opinion of the veterinarian of EF-UFLA. For statistical analysis, the frequency (%) of fecal samples with count of eggs per gram of feces (EPG) ≥300, count of oocysts per gram of feces (OoPG) ≥500 and fecal samples with count of cysts of Giardia spp. ≥1 were conducted. The overall average frequency of fecal samples with EPG ≥300, OoPG ≥500 and Giardia spp. cysts ≥1, respectively, was similar (p >0.05) between S-ST (20.3%; 17.3%; and 31.5%) and CT (26.4%; 23.9%; and 37.3%). The effective operational cost, per animal, in 12 months, was of R$ 784.58 (US$ 241.41) and R$ 83.90 (US$ 25.81) in S-ST and CT, respectively. The S-ST requires adjustments to be used as a technically efficient and economically viable alternative for the control of gastrointestinal parasitosis in female Holstein calves.

Resumo Na Fazenda Experimental da Universidade Federal de Lavras (FE-UFLA), Minas Gerais, Brasil, no dia do nascimento, bezerras da raça holandesa foram sorteadas de forma aleatória para compor um dos dois grupos, formados por 15 animais cada: Tratamento Estratégico-Seletivo (TE-S) ou Tratamento Convencional (TC). No TE-S, as bezerras foram tratadas após exames coproparasitológicos de acordo com critérios previamente estabelecidos pelos pesquisadores. No TC, as bezerras foram tratadas conforme orientação do veterinário da FE-UFLA. Em ambos grupos, as bezerras foram monitoradas a cada 14 dias, do nascimento até os 12 meses de idade, por meio de exames coproparasitológicos. Para análise estatística, considerou-se a frequência (%) de amostras fecais com contagem de ovos por grama de fezes (OPG) ≥300, contagem de oocistos por grama de fezes (OoPG) ≥500, e amostras fecais com contagem de cistos de Giardia spp. ≥1. A frequência média global de amostras fecais com contagem de OPG ≥300, OoPG ≥500 e cistos de Giardia spp. ≥1, respectivamente, foi similar (p >0,05) entre TE-S (20,3%; 17,3%; e 31,5%) e TC (26,4%; 23,9%; e 37,3%). O custo operacional efetivo, por animal, em 12 meses, foi R$ 784,58 (US$ 241.40) e R$ 83,90 (US$ 25.81) para TE-S e TC, respectivamente. O TE-S necessita de ajustes para que possa ser indicado como uma alternativa, tecnicamente eficiente e economicamente viável, no controle das parasitoses gastrointestinais em bezerras leiteiras.