Correlation of udder health with teat skin parameters

On four German farms, teat skin moisture, pH and udder health data (microbiological status and SCC of quarter foremilk samples) were obtained. The following tables summarise the mean and standard deviation of moisture and pH measurements per teat.

Tab. 80: Teat skin moisture, obtained on four German farms¹ (Trial 8)

Quarter 1 Cows sampled once separated from cows sampled twice

Tab. 81: Teat skin pH, obtained on four German farms¹ (Trial 8) 1 Cows sampled once separated from cows sampled twice

The results of the microbiological analysis are given in the following table in per cent of the number of quarters sampled.

Tab. 82: Quarter bacterial results of four different German farms, in per cent of quarters sampled (Trial 8)

Due to the sampling scheme, this data did not show the real microbiological status of the herds, but it demonstrated the status of the cows sampled during the trial.

Before the correlation of teat skin data with quarter health could be performed, the influence of factors that possibly affect the teat skin parameters were investigated.

Using the T-test for paired measurements, differences between the measurement locations barrel and tip were investigated, separate for cows with SCC of less than 100,000 per ml in quarter foremilk samples and normal secretion, and for cows with SCC of more than 100,000 per ml milk in all quarter foremilk samples. The following tables demonstrate the comparison of teat skin moisture or pH for barrel and tip; the data was summarised for front and back quarters.

Tab. 83: Comparison of locations on teat skin, for moisture and pH, cows with all quarters SCC < 100,000 and diagnosis = 1 (Trial 8)

Front teats Back teats

x sd P-value x sd P-value

* P ^ijkjlm,n-n/o0ijkj2p3m,n-n4n/o5ijk6j 01; NS: not significant; T-test for paired measurements

Tab. 84: Comparison of locations on teat skin, for moisture and pH, cows with all quarters SCC > 100,000 (Trial 8)

Front teats Back teats

x sd P-value x sd P-value

* P ^ijkjlm,n-n/o0ijkj2p3m,n-n4n/o5ijk6jj7pmq:r<stuvAwxytxzx{,|t,vm,} -test for paired measurements

The measurement location on teat had a significant influence on teat skin moisture and pH. Therefore, further analysis had to be done separately for the two locations.

In both groups of cows, moisture values for front and back teats were approximately the same. Significant differences were found between teat tip and barrel for moisture and pH.

To investigate, if an influence of ‘farm’ on teat skin parameters existed, an analysis of variance was performed, with quarters as repeated measurements.

Farms K2 and R2 were excluded from the analysis and only cows with SCC of less than 100,000 per ml milk and normal secretion were included.

Tab. 85: Influence of ‘farm’ on teat skin moisture (Trial 8)

Barrel Tip

Tab.86: Influence of ‘farm’ on teat skin pH (Trial 8)

Barrel Tip

Because it could not be concluded that the farm had no effect on teat skin moisture and pH, the following analyses were done for each farm separately. To investigate the influence of individual cows on teat skin parameters, an analysis of variance was performed, for cows with SCC of less than 100,000 per ml milk and normal secretion.

Tab. 87: Influence of ‘cow’ on teat skin moisture (Trial 8)

Barrel Tip

Tab. 88: Influence of ‘cow’ on teat skin pH (Trial 8)

Barrel Tip

Farm n (cows)

x (P-value) sd x (P-value) sd

R1 16 7.16 *** 0.24 7.14 ** 0.24

R2 9 7.18 ** 0.32 7.14 ^NS 0.38

K1 21 7.23 *** 0.33 7.18 *** 0.28

K2 12 6.93 ** 0.42 6.80 ^NS 0.42

W 9 7.22 *** 0.31 7.16 ** 0.32

S 8 7.51 ^{NS 0.33} 7.54 ^{NS 0.28}

* P ^£¤¥¤¦§,¨-¨/©0£¤¥¤2ª3§,¨-¨4¨/©5£¤¥6¤¤7ª§«:¬<­®¯°A±²³®²´²µ,¶®,°§·b®¶¸¹±²±e¯´º¶»²¶®µ,¼

The majority of results showed significant differences for cows in moisture and pH data. The individual cow influenced the teat skin moisture and pH in this trial.

Nevertheless, the following analysis was done as an average of all cows on farm, because analysing data on a cow level would not have resulted in statistically sensible results.

The next two tables summarise moisture and pH data for cows with mastitis on all four quarters. Although the numbers were small, an analysis of variance was performed, to test for the influence of the individual cow on teat skin moisture and pH.

Tab. 88 a: Influence of ‘cow’ on teat skin moisture, cows with 4 quarters with

Tab. 88 b: Influence of ‘cow’ on teat skin pH, cows with 4 quarters with diagnosis = 4 (Trial 8)

The influence of the teat position was investigated next, using an analysis of variance and cows with quarter SCC level smaller than 100,000 per ml milk and normal secretion.

Tab. 89: Influence of ‘teat position’ on teat skin moisture, tip of teat (Trial 8)

x moisture

Tab. 90: Influence of ‘teat position’ on teat skin pH, tip of teat (Trial 8)

Tab. 91: Influence of ‘teat position’ on teat skin moisture, barrel of teat (Trial 8)

x moisture

Tab. 92: Influence of ‘teat position’ on teat skin pH, barrel of teat (Trial 8)

x pH

No significant differences in teat skin moisture or pH between quarters were obtained. The results indicated that the quarter had no influence on teat skin moisture or pH.

After establishing that measurement ‘location on teat’ and ‘farm’ influenced the teat skin parameters, the teat skin data was correlated with the quarter health data. The subsequent table demonstrates the coefficients of correlation individually for each farm and location on teat.

Tab. 93: Correlation of ‘diagnosis’ with teat skin moisture and pH

Moisture pH

Farm

Barrel Tip Barrel Tip

R1 0.03 ^NS -0.01 ^NS -0.07 ^NS 0.02 ^NS

R2 0.13 ^NS 0.02 ^NS -0.01 ^NS -0.07 ^NS

K1 0.00 ^NS -0.03 ^NS 0.04 ^NS -0.02 ^NS

K2 0.05 ^NS 0.20 ** 0.05 ^NS 0.01 ^NS

W -0.09 ^NS -0.03 ^NS 0.10 ^NS 0.10 ^NS

S -0.06 ^NS -0.07 ^NS -0.06 ^NS -0.10 ^NS

* P ^ñòóòôõ,ö-ö/÷0ñòóò2ø ; *** P ñòó6òò7øõù:ú<ûüýþAÿüü,þõ /ýþýü

The majority of comparisons between diagnosis and moisture or pH, showed no significant correlation. No interaction between udder health and teat skin data was found.