Lescourret F, Coulon J B
Laboratoire d'Ecopathologie, Institut National de la Recherche Agronomique, Saint-Genès Champanelle, France.
J Dairy Sci. 1994 Aug;77(8):2289-301. doi: 10.3168/jds.S0022-0302(94)77172-1.
Individual milk production curves of 542 cows with 722 cases of mastitis were compared with control curves drawn from healthy lactating cows. First, differences were classified into patterns of milk loss, and their distribution was analyzed among the patterns with regard to breed, season, lactation number, stage of lactation, and milk production. Then, individual milk losses were estimated and analyzed according to the same factors. In early lactation, almost 7% of mastitis cases necessitated culling or drying off. For 36% of the cases of mastitis occurring in early lactation, milk production was affected for an extended period, and the milk loss induced was 911 kg on average over the entire lactation. Fifty-two percent of the mastitis cases occurring after lactation peak was not accompanied by marked modifications of the lactation curves. For 38% of cases of mastitis occurring from mid to late lactation, milk production was affected for an extended period. When milk production was the most affected (26% of total cases), the average loss was 850 kg over the entire lactation. For cases in early or mid to late lactation, the production at mastitis onset was a determining factor of the amount and pattern of milk production loss induced. Results were applied in a simulation over two simulated groups of cows.
将542头奶牛发生722例乳腺炎的个体产奶曲线与从健康泌乳奶牛绘制的对照曲线进行比较。首先，将差异分类为产奶量损失模式，并分析其在品种、季节、泌乳次数、泌乳阶段和产奶量等模式间的分布。然后，根据相同因素估计并分析个体产奶量损失。在泌乳早期，近7%的乳腺炎病例需要淘汰或干奶。对于泌乳早期发生的36%的乳腺炎病例，产奶量在较长时期内受到影响，整个泌乳期平均产奶量损失为911千克。泌乳高峰期后发生的乳腺炎病例中，52%未伴随泌乳曲线的明显变化。对于泌乳中期至晚期发生的38%的乳腺炎病例，产奶量在较长时期内受到影响。当产奶量受影响最大时（占总病例的26%），整个泌乳期平均损失为850千克。对于泌乳早期或中期至晚期的病例，乳腺炎发病时的产奶量是导致产奶量损失量和模式的决定性因素。结果应用于两组模拟奶牛的模拟中。
