我国16省(市)3岁及以上人群桶装和瓶装饮用水消费状况及其影响因素分析

目的分析我国16个省(市)3岁及以上人群桶装和瓶装饮用水消费状况及影响因素,为开展相关食品安全风险评估提供科学依据。方法利用国家食品安全风险评估中心2013—2014年开展的我国16个省(市)居民食物消费状况调查中预包装饮用水消费数据,选取43 319名3岁及以上人群作为研究对象,使用SAS 9.4统计软件进行数据清理和统计分析,采用χ~2检验和Kruskal-Wallis秩和检验方法,分析研究对象桶装和瓶装饮用水的消费状况及其影响因素。结果我国16个省(市)3岁及以上人群桶装和瓶装饮用水的消费率分别为26.2%和14.4%,人群平均消费量分别为249.7和56.4 mL/d,饮用者平均消费量分别为951.6和392.2 mL/d。男性桶装和瓶装饮用水消费率和消费量均高于女性;家庭年人均收入1万元以下人群桶装饮用水消费率和消费量均高于其他收入人群,3万元以上人群瓶装饮用水消费率和消费量均高于其他收入人群;城市地区人群瓶装饮用水消费率和消费量高于农村地区人群,而农村地区人群桶装饮用水消费率和消费量高于城市地区人群。此外,桶装和瓶装饮用水的消费状况还受年龄、文化程度等因素影响。结论我国3岁及以上人群桶装和瓶装饮用水消费率和消费量较低,其消费状况与年龄、文化程度、家庭年收入、地区等因素相关。     

我国3岁及以上城市居民焙烤食品消费量及其游离糖摄入评估

目的 了解我国3岁及以上城市居民焙烤食品消费量、来源于焙烤食品游离糖摄入量及其供能比。方法采用多阶段分层与人口成比例的整群随机抽样方法,在我国18个省,采用非连续3天24小时回顾方法,收集13 083名3岁及以上城市居民的焙烤食物消费量。焙烤食品糖含量数据来源于国家食品安全风险评估中心开展的焙烤食品专项监测数据。采用简单分布评估方法计算我国3岁及以上城市居民通过焙烤食品的糖摄入量及供能比。结果 我国3岁及以上城市居民(一般人群)的焙烤食品消费率为24.11%,女性略高于男性,分别为25.69%和22.42%。随年龄增加,各年龄组焙烤食品消费率总体呈下降趋势,3～5岁组最高为39.09%,60岁以上组最低,为17.57%。一般人群焙烤食品平均消费量为10.25 g/d,女性(10.58 g/d)略高于男性(9.92 g/d);各年龄组焙烤食品平均消费量最高为13～17岁组(16.36 g/d),6～12岁组和3～5岁组次之,分别为15.22 g/d和13.25 g/d。一般人群通过焙烤食品游离糖的平均摄入量为1.54 g/d,平均供能比为0.37%(0.37%TE),女性(1.60 g/d,0.41%TE)高于男性(1.47 g/d,0.33%TE);各年龄组,13～17岁组游离糖摄入量最高,为2.21 g/d(0.52%TE),6～12岁组和3～5岁组摄入量次之,分别为2.14 g/d(0.59%TE)和1.94 g/d(0.65%TE)。焙烤食品消费人群平均供能比为1.53%TE(1.43%TE～1.67%TE),焙烤食品消费人群的高消费者(P₉₅)为3.86%。一般人群,通过面包和糕点摄入的游离糖平均值分别为0.68 g/d和0.73 g/d,远高于饼干(0.13 g/d)。结论 我国3岁及以上城市居民一般人群,女性的焙烤食品消费率、游离糖摄入量、游离糖供能比均高于男性,通过焙烤食品摄入的游离糖水平较低。焙烤食品减糖时,建议重点关注3～5岁、6～12岁、13～17岁人群,重点关注面包和糕点这两类食品。     

我国9省(市)3岁以上人群碳酸饮料消费状况分析

目的了解我国3岁以上不同年龄、性别、地区、家庭年收入等人群的碳酸饮料消费状况。方法采用多阶段分层整群抽样方法,抽取北京、上海、广东、黑龙江、山东、湖北、江西、贵州、甘肃9个省(市),在9省(市)中各抽取1个城市的1个区和1个县3岁以上常住人群作为调查对象,共调查16 775人。利用非连续3 d 24 h回顾方法和过去1个月食物频率法收集调查对象碳酸饮料的消费状况,采用多元Logistic回归方法分析影响人群碳酸饮料消费的各类相关因素。结果我国9省(市)3岁以上人群碳酸饮料饮用率为24.2%(3 651/15 056),平均消费量为13.8 ml/d,其中,饮用碳酸饮料的人群平均消费量为172.9 ml/d。男性(16.9 ml/d)高于女性(13.8 ml/d),差异有统计学意义(P0.01);城市(20.3 ml/d)高于农村(7.8 ml/d),差异有统计学意义(P0.01);15~17岁年龄组人群的消费量最高为28.6 ml/d,60岁以上年龄组人群最低为2.7 ml/d,差异有统计学意义(P0.01)。结论我国人群碳酸饮料消费量与年龄、性别、城乡、职业和文化程度等因素相关。     

2017—2018年中国大城市成年居民蛋类食物消费状况分析

目的 了解2017—2018年我国大城市成年居民蛋类食物消费状况,为制定营养健康政策提供科学依据。方法 数据来源于“2017—2018年中国居民食物消费状况调查”,采用多阶段分层与人口成比例的整群随机抽样方法,在我国18个省（自治区、直辖市）33个大城市选取12 173名18岁及以上成人作为研究对象。利用非连续3 d 24 h回顾调查数据,分析研究对象蛋类食物消费率和消费量,采用χ²检验与秩和检验比较消费率和消费量的差异。结果 2017—2018年我国大城市成年居民蛋类食物消费率为72.9%（8 875/12 173）,全人群蛋类食物平均消费量为28.1 g/d（P25：0,P50：20.5 g/d,P75：43.9 g/d,P95：78.3 g/d）,消费人群平均消费量为38.6 g/d（P25：17.6 g/d,P50：33.3 g/d,P75：51.3 g/d,P95：86.9 g/d）。高文化程度、高家庭收入和东部地区的居民,蛋类食物的消费率和消费量较高。蛋类食物消费低于膳食推荐摄入量（40 g/d）的人群比例为71.5%（8 705/12 173）,满足推荐摄入量（40~50 g/d）的人群比例为9.9%（1 201/12 173）。结论 蛋类食物在我国大城市成年居民中的消费较为普遍,但人均消费量相对不足。建议针对蛋类食物的营养知识进行宣教科普,适量提高我国居民蛋类食物的消费量。     

2016-2017年中国中学生饮料消费现况分析

目的:描述和分析2016—2017年中国中学生饮料消费状况。方法:数据来自2016—2017年中国儿童与乳母营养健康监测,采用多阶段分层随机抽样的方法,研究对象为中国275个监测点29584名中学生。通过食物频率法的膳食调查问卷收集中学生的饮料消费情况。结果:2016—2017年中国中学生不同类型饮料总的消费率为72.8%,男生(75.3%)高于女生(70.3%),城市(76.9%)高于农村(69.1%),大城市、中小城市、普通农村和贫困农村,不同类型的饮料消费率依次降低。消费率最高的三类饮料依次是碳酸饮料(39.8%)、茶饮料(31.2%)和非100%果蔬汁饮料(26.0%)。消费饮料的中学生不同类型饮料总的消费频次的百分比依次为≥1次/天占29.9%、4~6次/周占18.5%、1~3次/周占40.0%、<1次/周占11.6%,1~3次/周百分比最高;消费饮料的中学生不同类型饮料总的日均消费量为267.6 g,男生(300 g/d)高于女生(233 g/d),城市(286.4 g/d)高于农村(248.5 g/d)。结论:2016—2017年中国中学生饮料消费水平较高,尤其是男生和城市中学生,需加强中学生相关的健康教育和干预,科学地引导其饮料消费。     

2017—2020年中国3～17岁儿童青少年烹调油消费状况分析

目的：分析2017—2020年中国23省（自治区、直辖市） 3～17岁儿童青少年烹调油消费现状。方法：数据来源于国家食品安全风险评估中心于2017—2020年开展的中国居民食物消费状况调查，采用多阶段分层与人口成比例的整群抽样方法，选取参与家庭调味品称重调查的3～17岁儿童青少年作为研究对象。通过称重记账法获得家庭烹调油消费量和人日数，结合家庭成员能量摄入比计算个体消费量，根据《中国居民膳食指南（2022版）》中烹调油推荐量进行评价。利用《中国食物成分表（第6版）》中各种脂肪酸含量，结合个体不同烹调油的消费量，计算个体通过烹调油摄入的不同脂肪酸量。结果：我国3～17岁儿童青少年烹调油的平均消费量为28.23 g/d，其中植物油为26.52 g/d、动物油为1.67 g/d、动植物混合油为0.04 g/d。研究人群烹调油消费在不同年龄、性别、居住地、收入水平和地域方面的差异均有统计学意义（P<0.05）。我国3～17岁儿童青少年烹调油消费量超过最高推荐量的比例为43.68%。菜籽油、花生油和芝麻油是消费率最高的3种烹调油，菜籽油、花生油和豆油是消费量最高的三种烹调油；经烹调油摄入的...     

我国3岁及以上居民碳酸饮料中添加糖摄入状况分析

目的了解我国3岁及以上居民碳酸饮料中添加糖的摄入状况。方法采用多阶段分层整群抽样方法,2014年在我国14个省(市)抽取28个城市区和县内的27 485名3岁及以上常住人群作为调查对象,利用非连续3 d 24 h膳食回顾法收集调查对象碳酸饮料的消费状况,结合2015年开展的饮料添加糖含量专项调查中132份碳酸饮料糖含量数据,采用简单分布评估方法计算人群碳酸饮料中添加糖摄入量分布和饮料提供的能量,并与人群膳食摄入总能量相比计算碳酸饮料中添加糖的供能比。结果我国14个省(市)3岁及以上居民碳酸饮料添加糖每日平均摄入量为0.5 g,供能比为0.11%,其中碳酸饮料消费人群添加糖每日平均摄入量为13.4 g,中位数为12.3 g,供能比为2.69%。不同消费人群添加糖每日摄入量的中位数比较,男性(15.3 g)高于女性(10.1 g),城市(13.8 g)高于农村(10.7 g),差异均有统计学意义(P0.05)。碳酸饮料中添加糖的供能比比较,男女之间差异无统计学意义(P0.05);城市(3.02%)高于农村(2.01%),差异有统计学意义(P0.05);13～17岁年龄组人群的碳酸饮料供能比最高为3.41%。结论 13～17岁青少年为碳酸饮料中添加糖的高消费群体,应重点开展科普宣教,引导合理消费。     

2017—2020年中国18～59岁成年居民烹调油消费状况

目的 分析2017—2020年中国23省（自治区、直辖市）18～59岁成年居民烹调油消费水平和状况。方法 数据来源于国家食品安全风险评估中心于2017—2020年开展的中国居民食物消费状况调查,采用多阶段分层与人口成比例的整群随机抽样方法,本研究选取参与家庭调味品称重调查的18～59岁成年居民作为研究对象。通过称重记账法获得家庭烹调油消费量和个人人日数,结合家庭成员能量摄入比分配到个人,并参照《中国居民膳食指南》中成年人烹调油的推荐摄入量25～30 g/d进行评价。根据《中国食物成分表（第6版）》中脂肪酸含量,结合个人不同烹调油的消费量,计算个人经烹调油摄入的脂肪酸含量。结果 我国18～59岁成年居民烹调油的平均消费量为36.23 g/d,其中植物油为33.99 g/d,动物油为2.17 g/d,混合油为0.08 g/d（动植物混合油）。研究人群烹调油消费量在不同年龄、性别、居住地、收入水平、受教育程度和地域方面的差异均有统计学意义（P<0.05）;我国18～59岁成年居民烹调油消费量超过推荐摄入量范围最高值30 g/d的个体比例为50.72%;菜籽油、花生油和芝麻油是消费率最高...     

我国3岁及以上城市居民含糖饮料消费状况及其游离糖摄入评估

目的 了解我国3岁及以上城市居民含糖饮料消费状况,评估含糖饮料的游离糖摄入量及其供能比.方法 采用多阶段分层与人口成比例的整群随机抽样方法,在我国18个省(自治区、直辖市),采用非连续3 d 24 h回顾调查方法,收集13 083名3岁及以上城市居民的各类食物包括含糖饮料的消费量.含糖饮料游离糖的含量数据来源于国家食品...     

2017—2020年中国老年居民烹调油消费状况

目的 分析2017—2020年中国23省（自治区、直辖市）60岁及以上老年居民烹调油消费现状。方法 数据来源于国家食品安全风险评估中心于2017—2020年开展的中国居民食物消费状况调查，采用多阶段分层与人口成比例的整群抽样方法，选取参与家庭调味品称重调查的60岁及以上老年居民作为研究对象。通过称重记账法获得家庭烹调油消费量和人日数，结合家庭成员能量摄入比计算个体消费量，根据《中国居民膳食指南2022》中烹调油推荐量进行评价。利用《中国食物成分表（第6版）》中各种脂肪酸含量，结合个体不同烹调油的消费量，计算个体通过烹调油摄入的不同脂肪酸量。结果 我国老年居民烹调油的平均消费量为32.32 g/d，其中植物油为30.36 g/d，动物油为1.89 g/d，动植物混合油为0.08 g/d；不同年龄、性别、居住地、收入水平、受教育程度和地域的研究人群的烹调油消费量差异均有统计学意义（P<0.05）；我国老年居民烹调油消费过多者占比43.84%；菜籽油、花生油和芝麻油是消费率最高的烹调油，菜籽油、花生油和豆油是消费量最高的烹调油；经烹调油摄入的脂肪酸主要以不饱和脂肪酸为主。结论 我国老年居民烹调油消费水平总体较高，超过40%的老年居民烹调油消费过多，应实施针对性行动并继续开展监测了解其消费情况。     

Moderate Alcoholic Beer Consumption: The Effects on the Lipid Profile and Insulin Sensitivity of Adult Men

Beer is the most consumed alcoholic beverage in the world. The purpose was to compare the effects of consuming alcoholic beer (AB) and nonalcoholic beer (NAB) on the biochemical blood parameters. Two beers were produced under known and controlled conditions from the same raw material, NAB (0.6%, v/v) and AB with the addition of 6% grain alcohol. Fifteen healthy adult men (aged 20 to 57 y) underwent 3 treatments (30 d per treatment). In Treatment 1 (Baseline), they followed their usual diet without drinking any alcoholic beverage; in Treatment 2, they added the daily consumption of 330 mL NAB; and in Treatment 3, they added the daily consumption of 330 mL AB. It was found that the use of AB for 30 d (16 g alcohol/d) reduced the blood insulin and fasting glucose, reducing insulin resistance. These data suggest that the daily intake of 330 mL AB could statistically change the lipid profile and insulin sensitivity of adult men. The volunteers were healthy before and remained so after the intervention, with no change in their clinical status.     

1989-2009年广西六市（县）居民膳食结构变化趋势分析

目的：分析广西城乡居民食物消费状况,了解居民膳食结构变化趋势.方法：利用1989、1991、1993、1997、2000、2004、2006、2009年“中国健康与营养调查”项目8次追踪调查资料,选取18-60岁居民作为调查对象,采取连续3d 24h膳食回顾法,获得居民每人每天食物消费量.结果：1989-2009年广西18-60岁居民谷类、豆类摄入量呈逐年下降趋势,尤其是谷类食物由1989年的483.5±116.3g/d,下降到2009年的389.0±133.0g/d,下降幅度为19.5％;蔬菜类食物的摄入量变化不大,基本维持在335.8-348.6g/d;水果、奶类、鱼虾类、蛋类食物摄入量和消费率虽然逐年均有所增加,但摄入量和消费率严重偏低;而禽畜肉摄入量却呈逐年上升趋势,由1989年的89.2±78.7g/d,上升至2009年的159.6±87.9g/d,上升幅度为78.9％;食用油、盐摄入量也偏高,至2009年分别达到38.8g/d和7.7g/d,超过推荐量标准.结论：21年间广西居民的膳食结构模式已从植物性膳食向动物性膳食转变,应引起高度关注.     

Role of peripartum dietary propylene glycol or protected fats on metabolism and early postpartum ovarian follicles

Eighty multiparous cows were used to test the effects of feeding a supplement containing 55% dry propylene glycol (PGLY), prilled fat (PrFA) containing a low proportion of unsaturated fatty acids (FA), or calcium soaps of long-chain FA (CaLFA) containing a high proportion of unsaturated FA on energy balance (EB), blood metabolites, and early postpartum (PP) ovarian follicles. Dry cows (256 d pregnant) were divided into 6 groups and began the following dietary treatments: 1) control group, fed a dry cow diet and fed a lactating cow diet PP; 2) PGLY group, diet supplemented with 500 g/d per cow of dry PGLY prepartum through 21 d in milk; 3) PrFA:control group, diet supplemented with 230 g/d per cow of PrFA prepartum and fed the control diet PP; 4) PrFA:PrFA group, diet supplemented with 230 g/d per cow of PrFA prepartum through 21 d in milk; 5) CaLFA:control, supplemented with 215 g/d per cow of CaLFA prepartum and fed the control diet PP; 6) CaLFA:CaLFA, supplemented with 215 g/d per cow of CaLFA prepartum through 21 d in milk. Follicular fluid was aspirated from follicles ≥6 mm on d 12 PP. The daily average calculated EB during the first 21 d in milk was lower in the PrFA:PrFA (−4.16 Mcal/d) and CaLFA:CaLFA (−3.64 Mcal/d) groups than in the control (−1.71 Mcal/d) and PGLY (−2.19 Mcal/d) groups. Postpartum plasma β-hydroxybutyrate was higher, and insulin concentrations were lower in the PrFA:PrFA (6.2 mg/dL and 126.1 pg/mL, respectively) and CaLFA:CaLFA (7.0 mg/dL and 130.7 pg/mL) groups than in the control (4.5 mg/dL and 274.5 pg/mL) and PGLY (4.3 mg/dL and 272.6 pg/mL) groups, whereas nonesterified FA concentrations were higher only than the control group. Postpartum nonesterified FA were 21% lower and insulin plasma concentrations were 86% higher in the CaLFA:control group as compared with the PrFA:control group. The progesterone concentrations in the follicular fluid of estradiol-active follicles were higher in the CaLFA:CaLFA (200.7 ng/mL) group than in all other groups (57.3 to 92.4 ng/mL), and androstenedione and estradiol concentrations were higher (54.2 and 1,049.1 ng/mL, respectively) than in the PGLY (15.5 and 440.1 ng/mL), PrFA:control (22.6 and 314.1 ng/mL), and CaLFA:control (17.5 and 451.9 ng/mL) groups. In conclusion, supplementation of protected fat during the peripartum period negatively affected the EB status of the cows. Neither fat supplementation nor PGLY influenced the development of ovarian follicles during the early PP period, but feeding fat containing a high ratio of unsaturated FA (CaLFA) increased progesterone concentrations in estradiol-active follicles that were aspirated at 12 d in milk.     

Farm-level factors associated with lameness prevalence,productivity, and milk quality in farms with automated milking systems

Impaired locomotion (lameness) may negatively affect the ability and desire of cows to milk voluntarily, which is a key factor in success of automated milking systems (AMS). The objective of this study was to identify factors associated with herd-level lameness prevalence and associations of lameness and other farm-level factors with milking activity, milk yield, and milk quality in herds with AMS. From April to September 2019, 75 herds with AMS in Ontario, Canada, were visited, and data on barn design and farm management practices were collected. Data from AMS were collected, along with milk recording data, for the 6-mo period before farm visits. Farms averaged 98 ± 71 lactating cows, 2.3 ± 1.5 robot units/farm, 43.6 ± 9.4 cows/robot, 36.4 ± 4.9 kg/d of milk, a milking frequency of 3.01 ± 0.33 milkings/d, and a herd average geometric mean SCC of 179.3 ± 74.6 (× 1,000) cells/mL. Thirty percent of cows/farm (minimum of 30 cows/farm) were scored for body condition (1 = underconditioned to 5 = over conditioned) and locomotion (1 = sound to 5 = lame; clinically lame ≥3 out of 5 = 28.3 ± 11.7%, and severely lame ≥4 out of 5 = 3.0 ± 3.2%). Clinical lameness (locomotion score ≥3) was less prevalent on farms with sand bedding, with increased feed bunk space per cow, and on farms with non-Holstein breeds versus Holsteins, and tended to be less prevalent with lesser proportion of underconditioned cows (with body condition score ≤2.5). Severe lameness occurrence (farms with any cows with locomotion score ≥4) was associated with a greater proportion of underconditioned cows and in farms with stalls with greater curb heights. Herd average milk yield/cow per day increased with lesser prevalence of clinical lameness (each 10-percentage-point decrease in clinical lameness prevalence was associated with 2.0 kg/cow per day greater milk yield) and greater milking visit frequency per day, and tended to be greater with increased feed push-up frequency. Lesser herd average somatic cell count was associated with lesser clinical lameness prevalence, herd average days in milk, and proportion of overconditioned cows, and somatic cell count tended to be lesser for farms with sand bedding versus those with organic bedding substrates. The results highlight the importance of minimizing lameness prevalence, using of sand bedding, ensuring adequate feed access and feed bunk space, and maintaining proper cow body condition to optimize herd-level productivity and milk quality in AMS herds.     

复合菌发酵米乳饮料的配方优化及其储藏品质变化

以米粉和脱脂乳为主要原料,基于发酵米乳复配菌株适宜配比的优化,研究米乳饮料的配方及其储藏品质。比较商用酸奶发酵剂(保加利亚乳杆菌和嗜热链球菌)和植物乳杆菌ZSM-002在米乳中的发酵特性,确定发酵米乳复配菌株适宜配比;通过单因素和正交试验优化米乳饮料配方(米水比、脱脂乳加量、白砂糖加量、菌接种量、发酵时间和发酵温度);采用均匀设计试验,通过考察离心沉淀率确定复配稳定剂配比;最终研究优化米乳饮料的储藏品质。结果表明,商用酸奶发酵剂和植物乳杆菌ZSM-002以3:2复配效果较好;优化的米乳饮料配方为:米水比1:10 (g/mL)、复合菌3%、脱脂乳10%、白砂糖9%、复合稳定剂0.2%(海藻酸丙二醇酯60%,蔗糖脂肪酸酯0.2%,果胶38%,黄原胶1.8%),37 ℃发酵10 h,此条件下发酵米乳饮料的离心沉淀率为2.25%,滴定酸度为(17.03±0.92) °T,活菌数为(8.53±0.08)lg (cfu/mL),感官评分为(8.83±0.20)分;在4 ℃条件下储藏7 d后,其酸度为(34.2±1.56) °T,活菌数为(7.44±0.12)lg (cfu/mL),满足乳酸菌饮料益生菌存活数达到106 cfu/mL标准,制作的米乳饮料口感黏稠,有柔和的乳酸风味。     

A randomized controlled trial to evaluate propylene glycol alone or in combination with dextrose as a treatment for hyperketonemia in dairy cows

Our objective was to investigate the effect of i.v. dextrose as an adjunct therapy to oral propylene glycol on the resolution of hyperketonemia (HYK; blood β-hydroxybutyrate ≥1.2 mmol/L), disease incidence, and early lactation milk yield. Cows (n = 1,249) between 3 and 16 d in milk (DIM) from 4 New York dairy farms were screened once weekly for HYK for 2 wk. Those with HYK and no previous history of retained placenta, metritis, or HYK were randomly assigned to 1 of 3 treatment groups: 300 mL of oral 100% propylene glycol for 3 d (PG3); 300 mL of oral 100% propylene glycol for 3 d plus 500 mL i.v. 50% dextrose on d 1 (PG3D1); or 300 mL of oral 100% propylene glycol for 3 d plus 500 mL i.v. 50% dextrose on all 3 d (PG3D3). Cows with a blood β-hydroxybutyrate <1.2 mmol/L at initial screening were re-screened the following week and randomly assigned to the above treatment groups if blood β-hydroxybutyrate was ≥1.2 mmol/L. Cows were assessed for post-treatment HYK resolution 1 and 2 wk after initial HYK diagnosis. We collected farm-diagnosed occurrence of adverse events (sold, died, metritis, displaced abomasum, or ketosis) during the first 60 DIM and milk yield data from the first 10 wk of lactation from herd management software. We used mixed-effects multivariable Poisson regression models to assess the risk of post-treatment HYK resolution at 1 and 2 wk following initial HYK diagnosis and adverse event occurrence among treated cows. We used repeated-measures ANOVA to assess differences in average daily milk yield between treatments. The overall HYK incidence was 30.1% (n = 373). Sixty-four percent of cows (n = 237) were assigned to a treatment group in the first week (3 to 9 DIM), and 36% (n = 136) assigned the second week (10 to 16 DIM). The incidence of 1 or more adverse events during the first 60 DIM was 9.4% (n = 35). We found no effect of treatment on risk of post-treatment HYK resolution at wk 1 (PG3 56.9%, PG3D1 45.0%, PG3D3 50.0%) or wk 2 (PG3 60.0%, PG3D1 52.1%, PG3D3 59.5%) following initial diagnosis, or for risk of adverse event occurrence (PG3 7.4%, PG3D1 8.0%, PG3D3 12.6%). Average daily milk yield (mean ± SE) was similar between treatment groups (PG3: 42.7 ± 0.6 kg/d, PG3D1: 42.4 ± 0.6 kg/d, PG3D3: 42.6 ± 0.6 kg/d). The addition of dextrose for 1 or 3 d provided no improvement in resolution of ketosis assessed once weekly, reduction in adverse events during the first 60 d of lactation, or a difference in average daily milk yield during the first 10 wk of lactation.     

Associations among milk quality indicators in raw bulk milk

The objective of this study was to determine characteristics and associations among bulk milk quality indicators from a cohort of dairies that used modern milk harvest, storage, and shipment systems and participated in an intensive program of milk quality monitoring. Bulk milk somatic cell count (SCC), total bacteria count (TBC), coliform count (CC), and laboratory pasteurization count (LPC) were monitored between July 2006 and July 2007. Bulk milk samples were collected 3 times daily (n = 3 farms), twice daily (n = 6 farms), once daily (n = 4 farms), or once every other day (n = 3 farms). Most farms (n = 11) had direct loading of milk into tankers on trucks, but 5 farms had stationary bulk tanks. The average herd size was 924 cows (range = 200 to 2,700), and daily milk produced per herd was 35,220 kg (range = 7,500 to 105,000 kg). Thresholds for increased bacterial counts were defined according to the 75th percentile and were >8,000 cfu/mL for TBC, >160 cfu/mL for CC, and ≥310 cfu/mL for LPC. Means values were 12,500 (n = 7,241 measurements), 242 (n = 7,275 measurements), and 226 cfu/mL (n = 7,220 measurements) for TBC, CC, and LPC, respectively. Increased TBC was 6.3 times more likely for bulk milk loads with increased CC compared with loads containing fewer coliforms. Increased TBC was 1.3 times more likely for bulk milk with increased LPC. The odds of increased TBC increased by 2.4% for every 10,000-cells/mL increase in SCC in the same milk load. The odds of increased CC increased by 4.3% for every 10,000-cells/mL increase in SCC. The odds of increased CC increased by 1% for every 0.1°C increase in the milk temperature upon arrival at the dairy plant (or at pickup for farms with bulk tank). Laboratory pasteurization count was poorly associated with other milk quality indicators. Seasonal effects on bacterial counts and milk temperature varied substantially among farms. Results of this study can be used to aid the interpretation and analysis of indicators of milk quality intensively produced by dairy processors’ laboratories.     

Effect of liquid flavor supplementation of the diet on dairy cows in the transition period

A 9-wk trial was conducted to study the performance of 24 Holstein cows during the transition period (3 wk prepartum to 6 wk postpartum). Cows were assigned to either a control or liquid-flavored (0.52 mL/kg of feed) total mixed ration in a randomized complete block design. The diets contained corn silage, alfalfa haylage, cottonseed, and a grain mix based on ground corn and soybean meal. Cows were fed to ensure 10% orts, and the diet provided (on a dry matter basis) 13% crude protein, 32% acid detergent fiber, 44% neutral detergent fiber, and 1.54 Mcal/kg of NEL prepartum and 17.5% crude protein, 30% acid detergent fiber, 40% neutral detergent fiber, and 1.57 Mcal/kg of NEL postpartum. An additional 2.3 kg of alfalfa hay was fed during the first 5 d postpartum. Weekly means of dry matter intake (DMI), milk yield, milk protein, milk fat, SNF, somatic cell counts, and body weight (BW) were analyzed using a repeated measures procedure. There was no effect of treatment on these variables, and least squares means were 16.9 and 15.7 kg/d for DMI, 38 and 35.3 kg/d for milk yield, 3.10 and 3.11% for milk protein, 3.69 and 3.74% for milk fat, 8.37 and 8.16% for SNF, 1.99 x 10(5) and 4.33 x 10(5) for somatic cell count, and 631 and 651 kg for BW for cows fed control and flavored diets, respectively. Individual cow daily DMI data were fitted to an exponential model describing pre- and postpartum feed consumption [DMI = a - b x e(-c x t), where DMI was measured in kg, a = asymptotic DMI, b = potential fractional increase in DMI, c = fractional rate of increase in DMI, and t = days prior to calving or days in milk]. Fractional rates of increase in DMI were similar: 0.139 and 0.123/d for control and flavored diets, respectively. Data for both groups were separately analyzed using multiple regression with 3.5% fat-corrected milk as the dependent variable and BW and DMI as independent variables. More BW was mobilized per unit increase in 3.5% fat-corrected milk in cows fed the control than in cows fed the flavored diet. Cows fed the control diet tended to be in more negative energy balance during early lactation than cows fed the flavored diet. It was concluded that feeding flavor improved energy balance of cows in early lactation and may reduce the risk of health or reproductive problems.