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A Tool Box for Assessing Cow, Udder and Teat Hygiene


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A Tool Box for Assessing Cow, Udder and Teat Hygiene
Nigel B. Cook and Douglas Reinemann
University of Wisconsin-Madison
Madison, Wisconsin
Infection of the mammary gland with environmental bacterial pathogens is the most significant
udder health problem facing the dairy industry in North America. Forty years ago, Neave et al.
(1966) stated that the rate of new intra-mammary infection is related to the number of bacteria
that the teat end is exposed to, and several studies have made associations between clean
housing, clean cows and lower bulk tank somatic cell counts (Bodoh et al., 1976; Barkema et al.,
1998; Barkema et al., 1999). In addition, Bartlett et al. (1992) found that an index of
environmental sanitation based on the amount of manure on the cow and in her environment was
a predictor of the occurrence of coliform mastitis, and Ward et al. (2002) noted that in four study
herds, the lowest incidence of mastitis occurred in the herd with the cleanest cows and the most
satisfactory beds.
Despite the improvements made in so many other areas of the dairy industry, our ability to keep
cows clean and to reduce the bacterial load at the teat end has improved little. Increases in herd
size, poor stall design, infrequent alley scraping and manure removal, pressure for milkers to
increase parlor throughput, and changes in the availability and use of different bedding materials
have all worked against significant progress in this area. Moreover, our inability to accurately
document the effects of these failures has allowed detrimental changes in management to be
The clinician presented with an environmental mastitis problem must have a tool box at his/her
disposal that serves to communicate the problem of environmental contamination to the herd
owner, so that interventions can be made and improvements documented. This paper serves to
track environmental contamination from its sources (manure and bedding), through
contamination of the teat end and failure to adequately clean the teat, to contamination of the
milk and infection of the mammary gland.
The predominant sources of coliforms and environmental streptococci (S.uberis, S.dysgalactiae,
Enerococcus spp.) are manure and bedding materials. The cleaner we can keep the cows and the
lower the bacterial count of the bedding, the fewer problems we will see. The tools we have to
assess the degree of contamination in the environment are hygiene scores of the cows, culture of
the bedding and assessment of teat end contamination.
a. Tools to Assess Udder Contamination
Several different methods of hygiene scoring have been documented (Cook, 2002; Schreiner and
Ruegg, 2003; Reneau et al., 2005) and some have been used to prove that poor hygiene results in
udder health problems. Schreiner and Ruegg (2003) used the udder hygiene scoring system in
Figure 1 to document the degree of contamination of 1250 cows in 8 herds. Udder hygiene
scores averaged 22% score 3 and 4 and a significant association between poor udder hygiene and
increasing individual cow linear score and the prevalence of intramammary infection with an
environmental pathogen was reported. In fact, cows with udder scores of 3 and 4 were 1.5 times
more likely to be infected with a major pathogen than cows with scores of 1 or 2. The study
reported only a weak association between leg hygiene score and the prevalence of pathogen
isolation from the udder.
Figure 1. Udder hygiene scoring chart available from UW Extension. The chart is available at:
Reneau et al. (2005) used the more complex scoring system in Figure 2 to document hygiene in
1,093 cows in 8 herds and showed a significant association between udder and lower leg hygiene
and individual cow linear score measured within 2 days of recording.
Figure 2. Hygiene scoring system used by Reneau et al., (2005) which serves to document the
degree of manure contamination in 5 different areas using a 5 point scale.
While these hygiene scoring tools have been useful for research and documentation of the degree
of udder contamination, they do not communicate the reasons for manure contamination of the
udder very well. There are four basic manure transfer mechanisms to the udder, and the relative
importance of each differs with the type of housing under consideration:
1. Direct Transfer. Cows may lie down in a manure contaminated stall or bedded area (or
sometimes in a traffic alley!) and transfer bacteria directly to the udder.
2. Leg Transfer. Cows may walk through manure, coating their feet and legs, which
transfers bacteria to the teat ends when the cow lies down and the udder comes to rest on
one of the hind feet (Abe, 1999).
3. Splash Transfer. Cows walking though deep liquid slurry will splash manure up toward
the udder.
4. Tail Transfer. In some situations, the tail may become heavily contaminated with
manure and transfer bacteria to the rear udder and flank areas (Abe, 1999).
The pattern of manure contamination and the mechanism of transfer therefore becomes a very
important concept to communicate to the herd owner. With this knowledge, the most appropriate
intervention can be recommended and for that reason, the author uses a simplified multi-zone
hygiene scoring system (Figure 3), scoring the udder, lower legs and upper leg and flank zones
of cows on a 1-4 scale. For reasons of communication, the proportion of scores that are 3 and 4
are presented, rather than a mean hygiene score. During investigations, we typically score 20%
of the cows in each pen, or all of the cows in small herds.
Figure 3. A hygiene scoring card which documents the degree of manure contamination on a 1-4
scale for each of three zones, the udder, the lower leg and the upper leg and flank. The score
sheet is available at
The hygiene scoring data from 58 farms collected by the SVM food animal production medicine
group suggests that on average, 19% of udders are score 3 and 4 and have an elevated risk of
infection. While tie stall cows generally have cleaner lower limbs and less leg transfer, direct
transfer is the predominant means of manure contamination of the udder – from manure
deposited on the stall surface. Upper leg and flank scores are usually much poorer than in free
stalls, reflecting the risk associated with spending around 22 hours per day in a tie stall.
In contrast, the lower legs of free stall cows are far more contaminated than tie stall cows and leg
transfer is a significant risk for udder contamination. Splash transfer in poorly draining alleys is
also significant.
Table 1. Median and upper quartile proportion of hygiene scores 3 and 4 for each zone for
cows in 58 Wisconsin dairy herds by housing type (46 Free stall and 12 Tie stall).
Proportion Hygiene Scores 3 and 4 (%)
Udder Lower Leg Upper Leg and Flank
Median Top 25% Median Top 25% Median Top 25%
Free stall
n=46 19 11 59 47 15 8
Tie stall
n=12 19 10 22 15 27 17
There are many factors involved in creating the pattern of manure contamination observed in
cows on our dairy farms and these have been discussed in more detail elsewhere (Cook, 2004). A
very common finding however, is for cows in sand bedded herds to be cleaner than in mattress
herds bedded with sawdust (Table 3). This finding may be due to the cleaning effect of sand,
differences in cow behavior in barns with the two different types of bedding surface, and less
slipping and splash transfer in sand bedded herds.
Table 3. Least squares mean (SE) hygiene scores (Proportion scoring 3 and 4 for each zone)
obtained independently by two observers from a minimum of 20 cows in the high group
pen on 12 free stall herds (6 sand and 6 mattress) compared using 1-way ANOVA.
Proportion Hygiene Scores 3 and 4
Zone Sand Mattress
SE P Value
Udder 16.7 33.3 4.2 0.02
Lower Leg 39.2 74.2 8.6 0.02
Upper Leg
and Flank 1.7 11.7 2.1 0.01
b. Tools to Assess Bedding Contamination
In recent years, with the commercial availability of a service to perform bedding cultures at the
Udder Health Laboratory at the University of Minnesota, it has become routine to determine
bacterial contamination of the bedding. We typically compare fresh bedding material with that
sampled from beds after several days of use. We use a gallon ziplock bag to gather handfuls of
bedding from the rear of 10-15 stalls in each pen. The sample is mixed and sub-sampled into a
quart ziplock and frozen until the sample is sent on ice to the laboratory for analysis.
Recommendations from the literature suggest that the total count of bacteria in used bedding
must not exceed 1 million CFU/ml. However, while this threshold appears to be valid for organic
bedding materials, considerable experience from clinical investigations suggests that this
recommendation is flawed in the case of sand bedding.
Table 4 shows the median and upper and lower quartile bedding counts for coliforms and
streptococci for 82 sand bedding samples collected from 23 farms. These counts would suggest
that coliform mastitis would not be a risk, but streptococcal infection would be a major problem.
In fact, in these 23 herds, the proportion of mastitis due to gram negative pathogens averaged
75%, and mastitis due to streptococci was rarely a major problem.
Table 4. Coliform and streptococci counts (CFU/ml) for 82 used sand bedding samples from 23
Count CFU/ml
Used Sand Bedding
Samples Coliform Count Streptococci Count
Median 50,000 6,650,000
Upper Quartile 10,000 2,612,500
Lower Quartile 134,250 14,787,500
Thresholds used by the author differ from published data. We have found significant gram
negative mastitis problems (Klebsiella spp in particular) at a coliform threshold of 100,000/ml,
and this is typically used as our intervention level. Even lower counts have been used in very
cold weather during the winter. Streptococcal counts in sand can rarely be kept below 1 million
/ml, and high counts usually reflect the duration of sand retention in the beds – ie. we can keep
the count lower by increasing the turnover rate of the material.
We have successfully improved the rate of clinical mastitis and lowered herd BTSCC by
removing contaminated sand bedding and changing to coarser screened sand rather than fine
sand (Cook, 2006). The 1314 cow dairy shown in Figure 4 was suffering an extremely high gram
negative clinical case rate in the summer of 2002. Following sand removal and replacement, the
case rate was halved in 2 months and returned to target levels within 6 months.
Figure 4. Quarter cases of clinical mastitis by month before and after sand removal from the free
stalls in a 1314 cow dairy in November 2002.
2001 2002 2003 2004
More recently, a 1400 cow dairy was visited in February 2006 with contaminated compacted
sand stalls. The sand was removed and replaced with a coarse washed mason sand. Not only did
cow comfort improve, but clinical treatment rate and bulk tank SCC was halved within one
month (Figure 5). In these herds, we now keep the coliform counts in the bedding less than
10,000/ml and see many fewer gram negative clinical cases.
Figure 5. SCC response at a 1400 cow dairy where sand was removed from stalls in February
2006 and the fine sand replaced with coarse washed mason sand.
Test Date
SCC (X1000)
1ST LACT LNR SCR AVG 2+ Lact Linear Score Average SCC WEIGHTED AVG
Correlations between bedding counts and teat end contamination have been made (Zdanowicz et
al., 2004) and confirm that higher correlations are generally made for organic bedding than for
sand. In particular, the correlation between streptococcal sand bedding counts and teat end
counts is low (r=0.28, P=0.06), compared with that for Klebsiella spp (r=0.40, P<0.05). More
research is needed to fully understand the transfer mechanisms of pathogen groups from the
bedding to the udder, but in the mean time, these anecdotal reports confirm that dramatic
improvements in udder health can be achieved by lowering the teat end challenge from
contaminated bedding, and bedding culture has a role to play in quantifying this challenge.
c. Tools to Assess Teat Contamination
Teat end sanitation is important in reducing the number of bacteria at the teat end before the
milking unit is attached, thus reducing transfer of organisms from cow to cow by the milking
machine. Proper teat end disinfection can reduce teat surface bacteria by 75% (Ruegg et al.,
2000; Galton et al., 1984; Galton et al., 1986). Pre-dipping with a sanitizer was associated with
reduced pathogen content in milk (Hassan et al., 1999) and has been shown to be effective in the
control of environmental pathogens (Pankey, et al, 1987; Ruegg and Dohoo, 1997). While
cleaning teats with water and wiping dry reduces the number of microorganisms on the teat skin,
the reduction is significantly higher when teats are disinfected (Brito et al., 2000). Contact time
of 20-30 seconds is needed for effective disinfection for most sanitizers.
If washing is required to remove excess manure, the following methods have been demonstrated
to significantly reduce pathogen numbers: 1) only teats should be washed, 2) minimal water
should be used, 3) teats should be thoroughly dried (Rasmussen, 2000). The most important
portion of the teat disinfection process is thorough drying of teat ends. Air-drying is not a
satisfactory substitute for manual drying with an individual cloth or paper towel. Water on teats
aids in transporting bacteria and concentrating them at the opening of the teat canal. Cloth towels
were more effective than paper at removing pathogens in a study by Rasmussen et al., (1991).
When cloth towels are used they should be disinfected by washing with bleach or very hot water
and drying at high temperature in an automatic dryer (Fox, 1997).
The tools we have available to determine the degree of teat end contamination are culture of the
bulk tank and string samples from sub-groups within the herd, and direct swabbing and culture of
the teat ends.
Culture of Bulk Milk and String Samples
Bulk tank cultures are routinely submitted from many farms in North America. While they are
predominantly used to monitor for the presence of ‘contagious’ pathogens (Mycoplasma,
S.aureus and S.agalactiae), counts of coliforms and environmental streptococci (non-agalactiae
streps) are also made.
Unfortunately, high levels of environmental bacteria in the bulk tank are difficult to interpret and
frequently the wrong conclusions are made. In simple terms, coliforms and streptococci may
enter the bulk tank from three sources – udder infections from the cows, teat contamination from
manure and bedding, and from the milking machine itself if a biofilm exists. High coliform
counts do not automatically mean that the milkers are not cleaning teats adequately!
Often, culture of sub-populations within the herd, such as cows with the last 3 SCC tests
>200,000/ml, can enlighten the interpretation of bulk tank culture, as it is not uncommon to see
environmental pathogens from the bulk tank (such as Klebsiella spp and S.dysgalactiae)
represented in a high proportion of chronically infected cows which shed large numbers of
Sand bedded herds typically suffer very high levels of streptococci in the bulk tank. Bedding
counts can be extremely high and if sand particles are not removed from the teat end adequately,
then large numbers of streptococci can appear in the bulk milk. Often, adding an extra wipe to
the procedure in sand bedded herds can dramatically reduce the streptococci count in the bulk
tank milk.
Despite the difficulties in interpretation, samples of bulk tank milk or sub-samples of milk from
groups within the herd can be used to help monitor hygiene in the following ways:
1. A base line ‘low level’ of coliforms and streptococci must first be identified for the herd
or group being milked to answer the question – ‘what is the lowest achievable level based
on milking procedures?’
2. Deviations from the base-line can be tracked over time for milker shifts in order to
determine departures from the normal using string samples
3. If significant departures occur, the cow must be ruled out as a source using individual
cow culture, and the adequacy of teat preparation must be determined by visual
Provided that these guidelines are followed, herds may use culture of the bulk milk or of string
samples to determine the adequacy of teat cleaning by the milkers.
Visual Assessments of Contamination
Filter Socks can be visually assessed at the end of each milking or ‘string’ as an estimate of the
relative contamination of teats at the time the milking units are attached. It is also possible to
culture these filters to determine the major types and relative magnitudes of bacteria present on
teats and in udders at milking time.
To check the effectiveness of teat sanitation and drying, teat end swabs can be taken. A clean
swab can be rubbed across the end of the teat prior to unit attachment. A swab from a properly
prepared teat will remain clean, while a dirty swab indicates that teat preparation methods should
be improved (Figure 6). This technique may be of use on a small number of individual cows, but
unlike hygiene scoring, which cannot be easily influenced on the day of capture, it is very easy
for milkers to modify their teat preparation procedure to improve teat cleanliness scores over the
duration of data capture. As such, benchmarks for the proportion of teats that are too dirty have
not been developed and the test remains something that can only be used to demonstrate
effective teat prep on an individual cow basis.
Figure 6. Teat Cleanliness Scorecard developed by WestfaliaSurge, using a 4-point scale to
assess the degree of manure and bedding contamination at the teat end after completion of the
preparation procedure, prior to unit attachment.
Quantitative Assessment of Teat End Contamination
Several attempts have been made to quantify bacteria numbers on teats before milking using
swabs or rinses combined with subsequent plate culture methods. More recently,
bioluminescence assessment methods have been described. The need to assess automated teat
cleaning in robotic milking systems has spurred activity in this area. Slagjuis et al, used both a
cobalt tracer (2004a) and poppy seeds (2004b) mixed with manure and manually applied to teats
before cleaning to assess efficacy of teat cleaning. Meline et at. (2004) used Clostridium
tyrobutyricum spores added to a manure slurry and applied to teats before cleaning to assess
removal rates.
Knappstein et al. (2004) reported on the use of both total bacteria counts and ATP measurements
of teat swabs for assessing teat cleaning efficacy. They recommended an ATP based method as a
pragmatic evaluation of teat cleanliness on farms with either automatic or conventional pre-
milking preparation. To date, these methods have not found wide application for routine field use
because of their cost, complexity, large cow-cow variability and/or considerable variability
introduced by small changes in sample technique.
Efforts are underway to develop improved methods that are easier to use in the field and yet
provide useful information on the real bacterial challenge at the teat end.
The dairy industry in North America continues to face the daunting task of reducing new intra-
mammary infection rates from the environment. The changing face of the industry has not helped
our chances of improving hygiene. However, armed with some of the tools described in this
article, the investigator can determine the extent of manure contamination and the reasons for it,
evaluate the bedding material as a risk for infection, determine the effectiveness of teat end
preparation before milking, and monitor the sources of contamination of the bulk tank milk with
environmental pathogens. With these quantitative tools, interventions can be targeted at the most
appropriate areas on the farm and subsequent progress monitored.
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... Pathogenic microorganisms, also, can be transmitted during milking from one cow to another, most often to the next 6-8 cows [14][15][16]. It is a well-known fact that there is a connection between the cleanliness of the upper and lower parts of the extremities, ventral abdomen, tail, and especially the teats and udder of cows and the TBC in the milk [6,[17][18][19][20][21][22][23]. The presence of dirt on these parts of the cow's body, as a consequence of inadequate barn hygiene, especially bedding, can cause the TBC in the milk to increase signifi cantly [4,19,20]. ...
... It is a well-known fact that there is a connection between the cleanliness of the upper and lower parts of the extremities, ventral abdomen, tail, and especially the teats and udder of cows and the TBC in the milk [6,[17][18][19][20][21][22][23]. The presence of dirt on these parts of the cow's body, as a consequence of inadequate barn hygiene, especially bedding, can cause the TBC in the milk to increase signifi cantly [4,19,20]. The increase of the TBC can be additionally infl uenced by inappropriate hygienic procedures that are carried out before, during and immediately after milking cows [18,19,[23][24][25][26], as well as during inadequate milk cooling procedures [27]. ...
... The presence of dirt on these parts of the cow's body, as a consequence of inadequate barn hygiene, especially bedding, can cause the TBC in the milk to increase signifi cantly [4,19,20]. The increase of the TBC can be additionally infl uenced by inappropriate hygienic procedures that are carried out before, during and immediately after milking cows [18,19,[23][24][25][26], as well as during inadequate milk cooling procedures [27]. ...
Full-text available
The Total Bacterial Count (TBC) and the Somatic Cells Count (SCC) in the milk are important indicators of its hygiene and quality. Hygienic conditions in barns, milking procedures, udder hygiene before, during and after milking, milking machine hygiene, as well as milk cooling procedures immediately after milking, have direct or indirect influences on milk hygiene indicators. Poor results of milk hygiene quality, when it comes to SCC and TBC, which are often seen in dairy cattle farms in our country, indicate numerous omissions before and during milking. To determine the possibility of improving milk hygiene quality, training of extension service professionals and farmers was conducted, corrective and preventive measures were determined and the achieved state was monitored on 128 dairy farms where SCC and TBC were observed at regular monthly intervals for 6 months. The results showed a continuous statistically very significant improvement in hygienic conditions in barns, milking procedures, udder hygiene before, during and after milking, milking machine hygiene, as well as milk cooling procedures. This has contributed to a statistically very significant improvement in the hygienic quality of milk, both in SCC and TBC indicators, continuously from month to month, with a visible improvement at the end related to the beginning of the study period. At the begining and the end of survey 19.7% and 50.0% of milk samples belong to 1st class of milk quality, respectively, indicating a significant improvement after implementation of corrective measurements.
... Assessment of animal welfare conditions provides an opportunity to address ethical issues and also to improve the productive performance of dairy farms (Abeni and Bertoni 2009), as cow discomfort is known to hinder full development of the productive potential. Various different studies have demonstrated that some facility-related aspects, as well as management practices, may influence animal health, longevity and reproductive and productive performance (Cook and Reinemann 2007;Erina et al. 2008). Bach et al. (2008) found that milk production differed considerably among herds of similar genetic background and fed with the same ration. ...
... The proportions of cows with hygiene score >2 for legs, udder and flanks in all groups of farms included in the present study (Table 4) were higher than reported by Cook and Reinemann (2007) both for the 25% top-performing farms (47%, 11%, and 8% for legs, udder and flanks, respectively) and for the average-performing farms (59%, 19%, and 15%, for legs, udder and flanks, respectively). Although hygiene scores were far from optimal in any of the groups of farms in the present study, there were significant differences between top-performing farms and those in groups 3, 4 and 5. ...
... This was probably related to the better quality of bedding materials and bedding maintenance, and with the better cleaning practices used on top-performing farms. Clean resting areas and clean alleys contribute to cow cleanliness (Cook and Reinemann 2007) and lower incidence of hoof disease because humidity and dirtiness cause soft hoofs that are more likely to become damaged and infected (M€ ulling et al. 2006;Lagger 2007). A high incidence of lameness will in turn contribute to poor bedding and cow hygiene, as lame cows tend to lie down more time than healthy ones (Ito et al. 2010). ...
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The aim of the present study was to evaluate the effect of facility comfort level on animal-based welfare indicators as well as on productive and reproductive parameters of 187 dairy farms in the northwest of Spain. Fifty-eight facility-based parameters, which included both housing facilities and management parameters, were evaluated in each farm and used to classify the 187 farms in 5 groups (from 1: top farms to 5: worst farms). Animal-based welfare indicators and reproductive and productive parameters were compared among farm groups. Lameness score significantly differed (p < .005) in top farms (67% of cows having normal gait) versus groups 4 (55%) and 5 (53%). The proportion of cows with dirty lower legs and udder was lower (p < .05) in top farms (80% and 31%, respectively) than in groups 4 (92% and 51%) and 5 (95% and 56%). Other animal-based indicators were not different among farm groups. Heat detection rate was higher (p < .001) in top farms (56.5%) versus groups 4 (51%) and 5 (47%), and milk production/cow/day was also significantly higher (p < .001) in top farms (34.4 L) versus groups 3 (31.2 L), 4 (30.5 L) and 5 (27.4 L). Other reproductive or productive parameters were not different among farm groups. Facility-based measures were compared only between the top and worst farms. In top farms, most facility-based parameters met the welfare-related objectives, whereas in the worst farms only a few facility-based parameters met the welfare objectives. • Highlights • Fifty-eight facility-based parameters, including housing measures and some management practices, were evaluated and scored in 187 dairy farms. • Top-performing farms (i.e. with the best scores) had lower incidence of lameness and of cows with dirty legs and udder than poor-performing farms. • Top-performing farms had higher rates of heat detection and higher milk production/cow/day than poor-performing farms.
... Nessa etapa também foram avaliados os escores de limpeza e de locomoção dos animais (COOK; REINEMANN, 2007). A claudicação foi avaliada observando as vacas andando, por meio do sistema de pontuação de locomoção de Sprecher, Hostetler e Kaneene, (1997) onde 1 é igual a normal, 2 é igual a levemente coxo, 3 é igual a moderadamente coxo, 4 é igual a coxo e 5 é igual a severamente coxo. ...
... Vacas com escore de locomoção ≥ 3 foram classificadas como clinicamente manca (ECKELKAMP et al., 2016). A higiene foi avaliada usando um sistema variando de 1 a 4, onde 1 significa limpo e 4 significa imundo e sujo, analisando a limpeza do úbere e pernas traseiras (COOK; REINEMANN, 2007). ...
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O objetivo desse artigo é avaliar o conforto térmico de bovinos leiteiros confinados em instalações Compost Barn com base em índices de conforto térmico, parâmetros fisiológicos, escore de higiene e claudicação, por meio de análises estatísticas. A pesquisa foi realizada, em uma propriedade comercial do município de Três Corações no estado de Minas Gerais no período de verão e inverno de 2016. As variáveis microclimáticas e os escores de limpeza e de locomoção foram analisadas por meio dos procedimentos da análise de estatística descritiva. Os parâmetros fisiológicos foram submetidos a um delineamento experimental em blocos casualizados em parcela subdividida no tempo, por meio da análise de variância e teste de Scott-Knott. Aplicou-se a análise de correlação de Pearson. Não foi verificado estresse térmico nos animais na estação de verão e inverno. Os parâmetros fisiológicos se encontraram dentro dos limites de conforto animal. Existe um relacionamento maior entre a frequencia respiratória, temperatura superficial e temperatura retal e os índices de conforto animal no verão, quando comparada com o inverno. Para a análise dos escores, as vacas apresentaram uma melhoria na limpeza e um número muito baixo de vacas com problemas de cascos.
... A 10 × 10 cm gauze soaked in alcohol was used to swab the teat end. The scores were recorded using a 1-to a 4-category system (Cook and Reinemann, 2007). Dip coverage was assessed by visually observing all surfaces of the teat including the teat end and all sides of the teat barrel and evaluating whether or not dip was present. ...
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In many farms, the logistics of on-farm training are a limiting factor due to communication challenges in the workplace (i.e., cultural differences, language barriers, impaired listening skills) and limited access to industry professionals. The use of E-learning systems may help to improve communication and can be sensitive to cultural challenges. The objectives of this study were to (1) identify how many of the high-priority problems in the milking parlor relate to milker training in the areas of milking equipment and milking routine, (2) design and test an E-learning training system for dairy farm milkers related to milking equipment, and (3) gain feedback targeted to improve subsequent E-learning training modules. An interactive online training course on basic checks of the milking equipment was developed with a cloud-based authoring software. A total of 95 dairy farm workers on 15 commercial dairy farms in northern New York State (USA) were trained and participated in the study. Milk quality professionals performed an initial evaluation of 3 main areas: equipment analysis, milker assessment, and cow assessment. The 3 most important risk factors for mastitis were summarized for each farm. A training event was scheduled with milkers guided by a bilingual (English and Spanish) professional in milk quality. Over 50% of the farms (8/15) had one or more of the top 3 priorities involving problems with milking equipment, which milkers could have detected and reported to management. All participants completed the module, 95% stated that they felt capable of checking the equipment before milking, and 86% felt more confident in reporting equipment problems to the manager after having taken the course. There were also differences between managers' and milkers' statements on how and whether milking equipment training was offered or not on the farm. This can be explained due to the lack of or secondary to poor communication between managers and employees on training objectives and goals on the farm. Our results also show that milking equipment issues which milkers could detect and report are common on dairy farms and reinforces the need for additional milker training in this area.
... The teat end was cleaned with a swab and a four-point scale was used to describe the amount of manure and litter sticking to the swab: "Clean" (no manure, dirt or dip), "Dip present" (no manure or dirt), "Small amount of dirt and manure present" and "Larger amount of dirt and manure present". Cook and Reinemann [58] employed the scale after the preparation procedure prior to milking. In our study, it was used before cleaning the teat end and preparing the sampling at drying off and approximately 17 ± 3 days after calving. ...
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The aim of this study was to define the time-related period of intramammary infections and its relation to risk factors for intramammary infections and clinical mastitis at cow and quarter levels. In total, 269 German Holstein Frisian dairy cows on three farms in Northern and Eastern Germany were included in this study. Quarter milk samples were collected at dry-off, 3 ± 1 days after calving and 17 ± 3 days after calving, for cytomicrobiological examination. Risk factors at quarter-and cow-level associated with intramammary infections and clinical mastitis were recorded during the trial period. Data were analyzed using logistic regression procedures and odds ratios were calculated. Calving for the second time increased the odds of clinical mastitis during the first 100 days of lactation compared to cows calving for the third time or more. A high milk yield after calving was a risk factor for new infections, with environmental pathogens 17 ± 3 days postpartum. A body condition score after calving less than 3.5 was associated with a decreased risk of having an intra-mammary infection (IMI) with non-aureus staphylococci and coryneforms 3 ± 1 days postpartum and consistent body condition between dry-off and early lactation decreased the risk of intramammary infections after calving. The absence of a ring of hyperkeratosis at the teat apex shown at dry-off was associated with a lower risk of intramammary infections with environmental pathogens 17 ± 3 days postpartum. This study shows the important influence of the dry period and early lactation on intramammary infections and clinical mastitis postpartum in dairy cows. Udder quarters may have eliminated pathogens during the dry period in 43.6% of cases in this study. Additionally, new infections occurred during early lactation, so 5.1% more quarters were infected 17 ± 3 days compared to 3 ± 1 days postpartum. New infections can be traced to non-aureus staphylococci and Staphylococcus aureus from dry-off up until 3 ± 1 days postpartum, and to non-aureus staphylococci, Staphylococcus aureus and Streptococcus uberis, after calving. In total, 88.7% of the infected quarters showed new infections with another pathogen species 3 ± 1 days postpartum than at dry-off, and 89.2% of the quarters 17 ± 3 days postpartum than 3 ± 1 days postpartum. In conclusion, the early lactation has just as important an influence on intramammary infections postpartum in dairy cows as the dry period. There is the possibility that udder quarters eliminate pathogens during the early lactation, especially during the dry period. However, there is also the danger that new infections manifest, with a large proportion of new infections occurring after calving. Thus, additional control strategies are of great importance to prevent new infections occurring during early lactation as well as during the dry period to reduce negative effects on milk yield and culling hazards in dairy cows by minimizing the associated risk factors. Citation: Nitz, J.; Wente, N.; Zhang, Y.; Klocke, D.; Seeth, M.t.; Krömker, V. Dry Period or Early Lactation-Time of Onset and Associated Risk Factors for Intramammary Infections in Dairy Cows. Pathogens 2021, 10, 224.
... Locomotion scoring was performed from a clear posterior side angle, only while cows took at least 6 strides on flat flooring, making sure they exhibited no other gait aside from walking and were not stumbling, falling, defecating, urinating, or being restricted from free movement by a nearby cow (Flower and Weary, 2006). On the days when data loggers were attached and removed (6 occasions in total), cow hygiene was recorded using a hygiene scoring system (Cook and Reinemann, 2007: https: / / milkquality .wisc .edu/ ...
The objective of this study was to investigate associations of freestall design and cleanliness with cow lying behavior, hygiene, lameness, and risk of new high somatic cell count (SCC). Cows from 18 commercial freestall dairy herds (22 ± 15 cows/farm; mean ± SD) in Ontario, Canada, were enrolled in a longitudinal study. Four hundred focal cows that were <120 d in milk, had no mastitis treatment in the last 3 mo, and had an SCC <100,000 cells/mL at their most recent milk test were selected for the study. Data on SCC were collected through Dairy Herd Improvement Association milk testing (at ~5-wk intervals). Each farm was visited 5 ± 3 d (mean ± SD) after each milk test until 3 tests were completed (~105 d), for a total of 3 observation periods per cow. Elevated SCC was used as an indicator of subclinical mastitis. An incident of new high SCC was defined as a cow having SCC >200,000 cells/mL at the end of an observation period, when SCC was <100,000 cells/mL at the beginning of that period. Lying behavior was recorded for 6 d after each milk sampling, using electronic data loggers. Cows were scored during each period for lameness (5-point scale, with scores ≥3 = lame), body condition score (BCS; 5-point scale; 1 = thin to 5 = fat), and hygiene (4-point scale). Stall cleanliness was assessed during each period with a 1.20 × 1.65-m metal grid, containing 88 squares. The grid was centered between stall partitions of every tenth stall on each farm, and the squares containing visible urine or fecal matter (or both) were counted. Cow lying time averaged 10.9 ± 1.9 h/d. On average, cows with low BCS (≤2.5) spent 37 ± 16.6 min/d less time lying down than high-BCS cows (≥4.0). On average, cows tended to spend 36 ± 18.3 min/d more time lying down in deep-bedded versus mattress-based stalls. Mean proportion of soiled squares per stall was 20.1 ± 0.50%. Across farms, cow lying time decreased as the proportion of soiled squares per stall increased. A difference in daily lying time of ~80 more min/d was modeled for cows housed in barns with the cleanest stalls compared with those with the dirtiest stalls. Higher neck rail height [for every 1 SD (10 cm) increase] increased the odds (odds ratio = 1.5) of cows having a dirty upper leg–flank and udder. The odds of a cow having a dirty upper leg–flank, udder, and lower legs were 1.5, 2.0, and 1.9 times greater, respectively, for cows housed with dirtier stalls. Also, cows housed on farms with dirtier stalls had 1.3 times greater odds of being lame at the time of observation. Over the study period, 50 new high-SCC cases were detected, resulting in an incidence rate of 0.45 cases of new high SCC per cow-year at risk. No measured factors were detected to be associated with risk of a new high SCC. Overall, our results confirm that cows lie down longer in cleaner and more comfortable environments. Further, these results highlight the need for improved stall cleanliness to optimize lying time and potentially reduce lameness.
... Before calving, hygiene was scored weekly by 2 observers (interobserver reliability was evaluated by kappa coefficient using the FREQ procedure of SAS; κ ≥ 0.79) for each animal on a 1-to-4 scale using the University of Wisconsin-Madison Hygiene Scoring Card (Cook, 2007), where little or no manure above the coronary band = 1; small amounts of manure above the coronary band = 2; distinct manure above the coronary band with visible hair = 3; and solid manure extending high up the leg = 4. ...
Many dairy cows succumb to disease after calving. Disease risk may be affected by the cows' social environment and ability to perform maternal behaviors. In nature, cattle isolate from others and find seclusion to give birth; these behaviors may be limited in indoor group pens and could potentially affect the cows' ability to cope. The aim was to determine whether stocking density and a physical blind in prepartum bedded-pack group pens affected physiological biomarkers, disease risk, and hygiene of peripartum dairy cows. A randomized complete block designed with a 2 × 2 factorial arrangement of treatments was used. Approximately 3 wk before calving, 374 cows (primiparous = 127; multiparous = 247) were assigned randomly to 1 of 4 treatment pens with the following 2 factors: (1) high versus low stocking density (7.7 to 12.9 m² vs. 15.4 to 25.8 m² lying space per cow), and (2) presence or absence of a blind. The blind was created using plastic road barriers and plywood, a steel gate, and shade cloth. After calving, cows were moved into a freestall pen and milked 3 times per day. Blood was sampled on the day of enrollment (baseline; −24 d) and approximately −14, −7, 3, 7, 10, and 14 d relative to calving, to measure inflammatory (haptoglobin) and metabolic (nonesterified fatty acids and β-hydroxybutyrate) biomarkers. β-Hydroxybutyrate (≥1.2 mmol/L) was used to diagnose subclinical ketosis. Vaginal discharge was scored 3, 7, 10, and 14 d after calving, to diagnose metritis (none, mild, or severe). Hygiene was scored on −24, −14, and −7 d before calving. Before calving, haptoglobin was lower in pens with a blind. After calving, cows in pens with low stocking density before calving tended to be at greater odds of being diagnosed with metritis. Cows were more likely to have poorer hygiene scores in high stocking density pens. No treatment effects were detected for pre- and postpartum nonesterified fatty acids, β-hydroxybutyrate, postpartum haptoglobin, or subclinical ketosis. Results suggest that the provision of a blind and lower stocking density may be beneficial for reducing inflammation before calving. However, low prepartum stocking density might increase the odds of metritis after calving. Although the reason for this paradox is unclear, the effects of prepartum stocking density may require further exploration.
... Lamsal (2018) pointed out that prevalence of subclinical mastitis was high in cows with increasing hygiene score of rear body parts (lower leg, upper leg, flank and udder) that is with increasing unhygienic condition. For assessment of cow udder, rear & font part, hygiene standard method outlined by Reinemann and Cook, 2007 was used. Three main body parts of animal mentioned above were marked by the researcher, with scores; 1 for the cleanest of all, 2 for the one with dirt in 2-10% surface area, 3 for the one with 10-30% surface dirt and 4 for more than 30% of the dirt was marked to follow. ...
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Lameness remains a major concern for animal welfare and productivity in modern dairy production. Even though a trend toward loose housing systems exists and the public expects livestock to be kept under conditions where freedom of movement and the expression of natural behavior are ensured, restrictive housing systems continue to be the predominant type of housing in some regions. Factors associated with lameness were evaluated by application of multiple logistic regression modeling on data of 1,006 dairy cows from 56 tie stall farms in Bavaria, South Germany. In this population, approximately every fourth cow was lame (24.44% of scored animals). The mean farm level prevalence of lameness was 23.28%. In total, 22 factors were analyzed regarding their association with lameness. A low Body Condition Score (BCS) (OR 1.54 [95%-CI 1.05–2.25]) as well as increasing parity (OR 1.41 [95%-CI 1.29–1.54]) entailed greater odds of lameness. Moreover, higher milk yield (OR 0.98 [95%-CI 0.96–1.00]) and organic farming (OR 0.48 [95%-0.25–0.92]) appeared to be protectively associated with lameness. Cows with hock injuries (OR 2.57 [95%-CI 1.41–4.67]) or with swellings of the ribs (OR 2.55 [95%-CI 1.53–4.23]) had higher odds of lameness. A similar association was observed for the contamination of the lower legs with distinct plaques of manure (OR 1.88 [95%-CI 1.14–3.10]). As a central aspect of tie stall housing, the length of the stalls was associated with lameness; with stalls of medium [(>158–171 cm) (OR 2.15 [95%-CI 1.29–3.58]) and short (≤158 cm) length (OR 4.07 [95%-CI 2.35–7.05]) increasing the odds compared with long stalls (>171 cm). These results can help both gaining knowledge on relevant factors associated with lameness as well as approaching the problem of dairy cow lameness in tie stall operations.
Conceptually, there are 2 feeding strategies for avoiding over-conditioning, which can be problematic for gravid dairy heifers that have reduced dietary energy density requirements relative to younger animals: (1) diluting the ad libitum-fed diet with low-energy forages; or (2) offering a diet of greater nutrient density but intentionally restricting the DM available for consumption (limit-feeding). Our objectives for this study were to evaluate the effects of feedbunk restriction and feed push-up frequency on the growth performance of gravid Holstein dairy heifers. A total of 128 Holstein heifers (434 ± 46.7 kg) were enrolled in the trial. Heifers were blocked by weight, and assigned to 1 of 16 identical research pens (4 pens/weight block; 8 heifers/pen), where the mean initial body weight (BW; ± SD) for the 4 blocks were 491 ± 19.0, 450 ± 16.5, 419 ± 10.6, 374 ± 23.0 kg. Within each block, a 2 × 2 factorial arrangement of treatments was assigned; treatments consisted of feedbunk access [full (FUL) or restricted (RES] and feed push-up frequency [1.5- or 3.0-h intervals]. The RES treatment was applied by covering 2 of the 8 head-locking feed gates in assigned pens with plywood partitions, thereby creating a feedbunk-stocking rate of 133%. A total mixed ration diet composed of alfalfa haylage (60.5%), corn silage (38.0%), and mineral (1.5%) was offered once daily for 91 d; daily feed allotments (overall mean = 9.11 kg dry matter (DM)/d) were generally consumed entirely within 9 h of feeding. Nutrient intakes were not affected by push-up frequency or the interaction of main effects, but all intakes were affected by feedbunk access, except for DM and neutral detergent fiber expressed as a percentage of BW (overall means = 1.93 and 0.80%, respectively). In each case, intakes for FUL were greater than those observed for RES; for DM intake, this amounted to a difference of 0.20 kg/d between those main-effect treatments. After 91 d, heifers without feedbunk restriction exhibited greater final BW, but total gain and average daily gain differed only numerically between FUL and RES. Under the conditions of this trial, heifers were blocked by weight, such that BW were relatively uniform within each pen, and head-locking feed gates were used, which also provided some protection from adjacent aggressive heifers. These results suggest heifers can exhibit acceptable growth performance on high-forage diets in a limit-feeding program that includes moderate feedbunk restriction provided other forms of stress are minimized.
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Efficient production and har- vest of high quality milk is the goal of most dairy farmers. High quality milk consists of milk that is visually appealing, free of adulteration and that meets specific quality standards for somatic cell count (SCC) and bacteria. The high- est quality milk usually has a SCC of less than 200,000/ml. Many Wisconsin dairy farms are producing high
Udder preparations using premilking teat disinfectants, premilking teat dipping procedures, and types of paper towels were evaluated to determine their effects on bacterial counts in milk and on teats. Iodophor, sodium hypochlorite, and dodecyl benzene sulfonic acid teat disinfectant dips significantly reduced total bacteria in milk with no significant differences among disinfectants. Teats dipped with dodecylbenzene sulfonic acid had higher coliform counts, which may be attributed to the physical properties interfering with effective drying. Manual drying of teats with a paper towel further reduced bacterial counts in milk; length of manual drying time did not significantly change bacterial counts. Also, types of paper towels did not affect bacterial counts on teat ends. Data suggest that the benefit of manual drying in assuring dry teats is of primary importance compared with duration of manual drying and type of towel.
Information on variability of somatic cell numbers in Dairy Herd Improvement samples analyzed by the Filter-DNA method came from two field studies. Data consisted of 13,733 samples taken in 16 herds monthly for 2 yr in one sur- vey and 6285 observations in 134 herds each sampled once in the other. Mean cell numbers in the studies were 692,000 and 625,000 cells per ml. Median cell number in the 16 herds was 390,000 cells per ml. Herd percentages of cows over 1 million, between 500,000 and 1 million, and below 500,000 cells per ml averaged 17.9, 20.5, and 61.6 with wide ranges. Data were transformed to a log scale and analyzed with two models, one involving herd, year, season, and age and another involving management practices. Mean differences among herds, years, seasons, age of cows, and stages of lactation were large in the 16-herd study. The model of management practices found no associa- tion of herd size and cell numbers. Herds with parlor milking systems that dipped teats and practiced selective dry cow treatment had the lowest mean cell num- bers.
Forty-eight dairy herds in Ohio were selected as a stratified random sample for participation in a disease monitoring study to relate the prevalence of IMI with coliform and environmental streptococci to herd management and environmental conditions. Management and environmental conditions were assessed by farm inspection and by an interview with the dairy producers. A separate analysis for each independent variable identified many potential disease determinants. A multivariable analysis of a covariance model to predict the prevalence of coliforms had 6 model df (R2 = .47). Increased prevalence of coliform infection was associated with an increased amount of milk remaining in the udder after milking, use of free stalls, regular use of a running water wash, increased person hours per cow spent milking, and poor sanitation. The multivariable model for environmental streptococci used 5 model df (R2 = .51). Increased prevalence of environmental streptococci was associated with poor sanitation, increased number of days dry, use of tie stalls, no use of a shared wash cloth, and no use of an individual dry cloth.
Premilking teat preparations using individual paper or cotton towels for either 6 or 20 s to reduce bacteria and iodine residues from teat surfaces were determined through Latin square designs applied to 50 cows. A cotton towel used for 20 s was most effective in cleaning teats, probably because of the physical structure of the towel, physical action on teat surface, and scrubbing of the teat ends. Premilking teat preparation of 6 s was inadequate to clean teats and to avoid iodine residues in milk. Teat end erosions increased iodine residue in milk. Two days after a treatment period, iodine content in milk from iodophor-dipped groups was similar to that of the undipped control group. Against our expectation, teat dipping with a .25% iodophor teat dip caused higher iodine residue in milk than a .50% iodophor teat dip. Differences in formulations and inert ingredients of iodophor teat dips indicate a need for further studies.
Efficacy of premiliking teat disinfection (predipping) with good udder preparation was compared with good udder preparation alone on four well-managed, commercial dairy farms. Three teat dip formulations containing iodophor were used for predipping. Predipping reduced the rate of intramammary infection with major mastitis pathogens approximately 54%. Infection rate with esculin-positive streptococci and coliforms was reduced more than 51%. Udder infections with coagulase-negative staphylococci were not controlled by predipping.
Udder preparations that wet both udder surfaces and teats had the highest standard plate count in milk compared with methods that wet teats only. Physical action of cleaning teats with a dry towel lowered bacterial count compared with preparations wetting both udder surfaces and teats. Methods resulting in lowest bacterial counts were the use of water hose, wet towel, or premilking disinfectant teat dip followed by drying with paper towels. Counts of coliform and Staphylococcus sp. followed similar trends. In most comparisons, addition of udder wash sanitizer was of marginal or no benefit. Standard plate count of teat rinses after udder preparation confirmed the benefit of cleaning and drying teats. Physical manipulation of teats during cleaning was essential for lowering sediment in milk. Drying of teats with a paper towel for at least 10 s after dipping with a 1% iodophor disinfectant dip was essential for reducing iodine residue. Both premilking and postmilking disinfectant teat dipping with a 1% iodophor teat dip caused higher iodine residue in milk than premilking disinfectant dip with subsequent drying. A .5% iodophor teat dip contributed less iodine in milk than a 1% iodophor teat dip. Premilking udder preparation affects bacterial count, sediment, and iodine residue in milk.