Ojeda-Rojas O A, Pérez-Báez J, Casaro S, Chebel R C, Cunha F, De Vries A, Santos J E P, Lima F S, Pinedo P, Schuenemann G M, Bicalho R C, Gilbert R O, Rodriguez-Zas S, Seabury C M, Rosa G, Thatcher W W, Galvão K N
Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL 32610.
Instituto Nacional de Investigaciones Agropecuarias, Facultad de Ciencias Agronómicas y Veterinarias, Universidad Autónoma de Santo Domingo, Santo Domingo 10904, Dominican Republic.
J Dairy Sci. 2025 Mar;108(3):2710-2720. doi: 10.3168/jds.2024-24897. Epub 2024 Dec 9.
The goal of this study was to calculate the cost of purulent vaginal discharge (PVD) in dairy cows. The dataset included 11,051 cows from 16 dairy herds located in 4 regions of the United States. Purulent vaginal discharge was characterized as a mucopurulent, purulent, or reddish-brownish vaginal discharge collected at 28 ± 7 DIM. Gross profit was calculated as the difference between incomes and expenses, and the cost of PVD was calculated by subtracting the gross profit of cows with PVD from the gross profit of cows without PVD. Continuous outcomes such as milk production (kg/cow), milk sales ($/cow), cow sales ($/cow), feed costs ($/cow), reproductive management costs ($/cow), replacement costs ($/cow), and gross profit ($/cow) were analyzed using linear mixed effects models. Pregnancy and culling by 305 DIM were analyzed by generalized linear mixed effects models using logistic regression. Models included the fixed effects of PVD, metritis, parity, region, season of calving, and morbidity in the first 60 DIM, as well as the interactions between PVD and metritis, PVD and parity group, and PVD and morbidity. Farm and the interaction between PVD and farm were considered random effects in all the statistical models. A stochastic analysis was conducted using 10,000 iterations with varying relevant inputs. Cows with PVD produced less milk (9,753.2 ± 333.6 vs. 9,994.6 ± 330.9 kg/cow), were less likely to be pregnant (70.7 ± 1.7% vs. 78.9 ± 1.2%), and were more likely to be culled by 305 DIM (34.6 ± 1.7% vs. 27.2 ± 1.3%) compared with cows without PVD. Consequently, milk sales (4,744.7 ± 162.3 vs. 4,862.1 ± 161.0 $/cow) and residual cow value (1,079.6 ± 23.0 vs. 1,179.3 ± 20.3 $/cow) were lesser for cows with PVD. Replacement (639.4 ± 26.4 vs. 526.0 ± 23.4 $/cow) and reproductive management costs (76.3 ± 2.5 vs. 69.0 ± 2.4 $/cow) were greater for cows with PVD. The mean cost of PVD was $202. The stochastic analysis also showed a mean cost of $202, ranging from $152 to $265. The robust dataset and the stochastic analysis strengthen both the external and internal validity of our findings, offering a deeper understanding of the economic consequences of PVD. In conclusion, PVD resulted in large economic losses to dairy herds by being associated with decreased milk yield, impaired reproduction, and greater culling.
本研究的目的是计算奶牛脓性阴道分泌物（PVD）的成本。数据集包括来自美国4个地区16个奶牛场的11051头奶牛。脓性阴道分泌物的特征为在产后28±7天采集的黏液脓性、脓性或红棕色阴道分泌物。毛利润计算为收入与支出之间的差额，PVD的成本通过从无PVD奶牛的毛利润中减去有PVD奶牛的毛利润来计算。使用线性混合效应模型分析连续结果，如产奶量（千克/头）、牛奶销售额（美元/头）、奶牛销售额（美元/头）、饲料成本（美元/头）、繁殖管理成本（美元/头）、替换成本（美元/头）和毛利润（美元/头）。使用逻辑回归的广义线性混合效应模型分析到305天的妊娠和淘汰情况。模型包括PVD、子宫炎、胎次、地区、产犊季节和前60天发病率的固定效应，以及PVD与子宫炎、PVD与胎次组、PVD与发病率之间的相互作用。在所有统计模型中，农场以及PVD与农场之间的相互作用被视为随机效应。使用10000次迭代和不同的相关输入进行随机分析。与无PVD的奶牛相比，有PVD的奶牛产奶量更低（9753.2±333.6千克/头对9994.6±330.9千克/头），怀孕可能性更小（70.7±1.7%对78.9±1.2%），到305天被淘汰的可能性更大（34.6±1.7%对27.2±1.3%）。因此，有PVD的奶牛牛奶销售额（4744.7±162.3美元/头对4862.1±161.0美元/头）和剩余奶牛价值（1079.6±23.0美元/头对1179.3±20.3美元/头）更低。有PVD的奶牛替换成本（639.4±26.4美元/头对526.0±23.4美元/头）和繁殖管理成本（76.3±2.5美元/头对69.0±2.4美元/头）更高。PVD的平均成本为202美元。随机分析还显示平均成本为202美元，范围从152美元到265美元。强大的数据集和随机分析增强了我们研究结果在外部和内部的有效性，使我们对PVD的经济后果有更深入的了解。总之，PVD与产奶量下降、繁殖受损和更高的淘汰率相关，给奶牛群造成了巨大的经济损失。
