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1

Concentration of blood acetone during prepartum and the whole lactation in primiparous cows

100%
Bialon K. A., Skrzypek R.
Medycyna Weterynaryjna
|
2012
|
tom 68
|
nr 03
The aim of this study was to analyse the acetone concentration in the blood of cows in the period immediately preceding the first calving and during the whole first lactation. The study was conducted on 124 clinically healthy primiparous cows of Polish Holstein-Friesian breed born, reared and managed on the same farm (Agricultural Experimental Farm D³oñ) at least up to the second calving. Blood samples were collected from the animals according to the following schedule: 7-8 and 1-2 weeks before the expected calving, as well as 2, 5, 30 (± 3), 60 (± 3), 90 (± 3), 120 (± 3), 200 (± 3), and 280 (± 3) days after calving. The concentration of acetone was determined in the blood serum by the gas chromatography method. The mean acetone concentration in the blood of cows examined was 0.41 mmol/L (SD = 0.18). The highest acetone concentration, exceeding the physiological level (0.4 mmol/L), was noted 7-8 and 1-2 weeks before calving, and at 5, 200 and 280 days of lactation. The threshold corresponding to symptoms of clinical ketosis (above 2 mmol/L) was not exceeded in any of the samples. It was found that the blood acetone level is a feature of low repeatability (ρ up to 0.07). Significant positive correlations (p ≤ 0.01) were observed between acetone concentrations determined 30 to 120 days after calving (r from 0.26 to 0.39). Significant positive correlations (p ≤ 0.05) were also found between the acetone concentration before calving and in the first 60 days of lactation (r from 0.19 to 0.22), whereas no correlation was observed between concentrations determined before calving. The results obtained in this study prove that the blood acetone concentration in dairy cows is of special significance during late pregnancy because of a relatively high level of this ketone body and because of its impact on the blood acetone concentration in the initial phase of lactation.
2

Evaluation of the possibilities for the use of blood acetone concentration, body weight changes and milk and reproduction performances as indicators of dairy cow adaptation to metabolic stress during the initial period of lactation

100%
Bialon K. A., Skrzypek R.
Medycyna Weterynaryjna
|
2013
|
tom 69
|
nr 06
The study was conducted on 124 Polish Holstein-Friesian primiparous cows of the black-white variety. The aim was to determine the relationship between the following indicators of adaptation to metabolic stress occurring in dairy cows in the early lactation stage due to negative energy balance: acetone concentration in blood (AcC) on days 5, 30, 60 and 90 after calving; body weight changes between days 5-60 after calving (BWC); milk yield (MY), fat content (FC) and protein content (PC) in milk, fat to protein ratio in milk (FPR) during the first 100 days of lactation; calving to conception interval (CC) and the number of AI services per conception (NSC). The data were analyzed using logistic regression. It was found that AcC positively influenced BWC, FC and FPR (OR > 1.0), and negatively PC (OR < 1.0), while the influence on MY was variable on subsequent dates of the examination, i.e. positive on days 5 and 30, and negative on days 60 and 90. In terms of the particular dates of AcC examinations, particularly large relationships were noted on the 60th day after calving. It was also demonstrated that the relationship of AcC was reversible in the case of FC, and especially PC and FPR. With regards to fertility parameters, AcC and FPR influenced them to the highest degree on the 90th day after calving (OR from 6.4 to 8.9), and so did PC (OR between 0.3-0.4) and FC (OR between 1.1-1.9). Concluding, among the tested traits, FPR is of the highest diagnostic value as an early indicator of metabolic stress, generally observed in dairy cows during the early lactation stage. A similar diagnostic value may be attributed to AcC; however, the possibilities of applying this parameter in practice are considerably lower.
3
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Factors affecting acetone concentration in blood of dairy cows at the first stage of lactation

100%
Bialon K. A., Skrzypek R.
Polish Journal of Veterinary Sciences
|
2012
|
tom 15
|
nr 2
The aim of this paper was to determine effects of selected genetic and environmental factors on the concentration of acetone in blood of cows in the first trimester of lactation. The study included 124 Polish Holstein-Friesian primiparous cows born, reared and managed on the same farm. The samples of blood were collected on day 2, 5, 30, 60 and 90 after calving. The highest serum acetone concentration in the animals examined was observed on day 5 after calving. The level of this compound was inversely related to the contribution of the original Holstein-Friesian breed in gene pool. Significantly higher serum acetone level was observed in cows calved in January-March period when compared to other months of the year. Besides, the level of acetone determined on day 5 after calving was associated positively with body weight determined at the same day and negatively with body weight changes between days 5 and 60 after calving.
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