摘要
The objective of this study was to evaluate how herd management, barn design, and lameness relate to productivity and cow behavior in herds with automated milking systems (AMS). We visited 41 AMS farms in Canada (Ontario: n = 26; Alberta: n = 15), averaging 105 ± 56 (mean ± SE) lactating cows and 2.2 ± 1.3 AMS units. Details of barn design, stocking density, and herd management were collected. At each farm, 40 cows were gait scored (or 30% for herds > 130 cows) using a five-point numerical rating system (NRS; 1 = sound to 5 = lame). Cows were defined as clinically lame with NRS ≥ 3 (26.2 ± 13.0%) and severely lame with NRS ≥ 4 (2.2 ± 3.1%). For 6 d periods, we collected milking data from AMS units and lying data from electronic data loggers. Data were analyzed in multivariable mixed-effect linear regression models. At the herd level, an increase of 1 percentage point (p.p.) in the prevalence of severe lameness was associated with production losses of 0.6 kg of milk produced/cow/d (P = 0.05) and 32 kg milk harvested/AMS/d (P = 0.03), while each 10 p.p. increase in clinical lameness prevalence was associated with 0.1 fewer milkings/cow/d (P = 0.05). One additional cow/AMS unit was associated with 32 kg more milk harvested/AMS/d (P < 0.001), but also decreased milking frequency (–0.2 milkings/cow/d for each 10 additional cows/AMS; P < 0.001). Daily lying time was positively associated with the frequency of feed push-ups (+3 min/cow/d/push-up; P = 0.05) and negatively associated with the placement of neck rails from the rear curb of lying stalls, such that cows lied down less as neck rails were placed farther forward (–23 min/cow/d/10 cm; P = 0.03). Lying bouts (min/bout) were 12 min longer in deep-bedded stalls vs. mattresses (P = 0.003), and 5 min longer with each 10 p.p. increase in the prevalence of clinical lameness (P = 0.001). In a cow-level comparison (30 cows/farm) of lame (NRS ≥ 3: n = 353) and sound cows (NRS < 3: n = 865), lame cows were fetched more often (P = 0.002), produced 1.6 kg/d less milk (P = 0.002) in 0.3 fewer milkings/d (P < 0.001), and spent more time lying down (+38 min/d; P < 0.001) in longer bouts (+3.5 min/bout, P = 0.03). In conclusion, lameness is especially problematic for AMS herds, reducing productivity at the cow and herd level. Although few cows in our study were severely lame, producers need to identify and reduce clinical lameness. Widening lying stalls, providing deep-bedded stalls, and scraping alleys more frequently were factors associated with reduced lameness prevalence and are potential ways to optimize productivity in AMS herds.
摘要译文
本研究的目的是评估畜群管理，畜栏设计和跛足与自动挤奶系统（AMS）畜群生产力和奶牛行为的关系。我们访问了加拿大的41个AMS农场（安大略省：26个;艾伯塔省：15个），平均数为105±56头（平均值±SE）的泌乳奶牛和2.2±1.3个AMS单位。谷仓设计细节，放养密度，收集了牧群管理。在每个农场，使用五点数字评级系统（NRS; 1 \x3d声音为5 \x3d跛脚）对40头奶牛进行步态评分（或30％为牛群 130头奶牛）。奶牛被定义为NRS≥3（26.2±13.0％），严重不良伴NRS≥4（2.2±3.1％）的临床跛行。对于6天的时间，我们从AMS单元收集挤奶数据，并从电子数据记录器收集数据。在多变量混合效应线性回归模型中分析数据。在牧群层面上，严重跛行患病率增加1个百分点（p.p.）与产生的0.6 kg牛奶/牛/ d（P \x3d 0.05）和32 kg牛奶/ AMS / d（P \x3d 0。03），而每10 p.p.临床跛行患病率增加与乳汁/牛/ d比较少（P \x3d 0.05）。另外一头母牛/ AMS单位与更多产奶量32kg / AMS / d有关（P 0.001），但也会降低挤奶频率（每增加10头母牛/ AMS每头牛产奶量-0.2牛奶/牛/日; P 0.001）。每日躺卧时间与喂食俯卧撑的频率正相关（+3分钟/牛/天/俯卧撑; P \x3d 0。05）并且与从躺着的畜栏的后部路缘放置颈部导轨负相关，使得当颈部导轨更远地向前放置时，母牛躺下较少（-23分钟/牛/ d / 10cm; P \x3d 0。03）。在深床位和床垫（P \x3d 0.003）中，比较发作（min / bout）长12分钟，每10 p.p.更长5分钟。临床跛行患病率增加（P \x3d 0.001）。在一个奶牛级比较（30头奶牛/农场）的跛脚（NRS≥3：n \x3d 353）和健康奶牛（NRS 3：n \x3d 865）中，更常见的是跛行母牛（P \x3d 0.002） kg / d减去牛奶（P \x3d 0.002）0。减少3次挤奶/次（P 0.001），并且在较长的发作中花费更多的时间躺下（+38分钟/天; P 0.001）（+3.5分钟/回合，P \x3d 0.03）。总之，对于AMS畜群来说，跛足是特别有问题的，降低奶牛和畜群的生产力。虽然我们的研究中很少有奶牛严重跛脚，但生产者需要确定并减少临床跛足。放宽卧铺，提供深床铺位和更频繁地刮胡子是与跛行患病率降低相关的因素，并且是优化AMS畜群生产力的潜在方法。
M. T. King;E. A. Pajor;S. J. LeBlanc;T. J. DeVries. 0074 Lameness, productivity and cow behavior in dairy herds with automated milking systems[J]. Journal of Animal Science, 2016,94(Sup5): 34