[Course of the energy balance in the early lactation of Holstein-Friesian cows calculated according to 3 different models]. / Verlauf der nach 3 unterschiedlichen Formeln berechneten Energiebilanz bei Holstein-Friesian-Kühen in der Frühlaktation.

OBJECTIVE: The aim of this study was to compare the results of the energy balance of dairy cows calculated with 3 different formulas. The course of the energy balance up to the 100th lactation day in Holstein-Friesian dairy cows from a herd with a mean 305-day milk yield of 11 761 kg was to be described. MATERIALS AND METHODS: Data from a total of 193 dairy cows were available within 2 study periods. Body weight measurements were taken at fixed time points. The feed intake was determined by means of transponder-supported feeding troughs. Milk data was obtained from the corresponding milking recordings. Energy balance was determined by calculation according to the society for nutritional physiology (GfE), Jans and Kessler and National Research Council (NRC) modified according to Collard. RESULTS: The 3 models yielded very similar results. The calculation modified by Collard, however, generally led to lower values. Minimum values for energy balance were calculated in the colostrum phase. The transition from the negative to the positive energy balance occurred in the mean 53 days postpartum. CONCLUSION AND CLINICAL RELEVANCE: All 3 calculation methods were equally suitable to assess energy balance of dairy cows conveying similar results. Over 50 % of the examined cows reach a positive energy balance before the 60th day of lactation. According to the literature, the course of the energy balance with a low point around the 60th day postpartum is not to be assumed in principle for each herd. Strategies to improve negative energy balance with regard to time point, extent, and duration in the early lactation must be developed individually for each herd and still require research.

[Assessment of rumen fill in dairy cows for evaluation of the individual feed intake in herd management]. / Bewertung der Pansenfüllung von Milchkühen zur Beurteilung der individuellen Futteraufnahme in der Bestandsbetreuung.

OBJECTIVE: Postpartal disease complexes of dairy cows are frequently related to an insufficient feed intake around calving. The study examined the relationship between the rumen fill (RF) score and the feed intake. A further aim was to evaluate whether the RF score can be used in practice to estimate the cow's individual feed intake (in kg dry mass intake or fresh-mass intake per cow). MATERIAL AND METHODS: In pluriparous cows (n = 109), the RF was scored daily according to the schema of Zaaijer and Noordhuizen (2003) modified by half-points between day 24 (±â€…4 days) ante partum (a. p.) and day 9 post partum (p. p.) as well as on days 28 (±â€…2 days) and 60 (±â€…2 days) p. p. The individual feed intake per cow was recorded. Additionally, measurements of the feed intake were performed every 4 hours over 24 hours (24-hour daily profiles) in 21 cows a. p. and in 10 cows p. p. RESULTS: There was a significant relationship between the RF score and the feed intake both a. p. and p. p. The number of days in milk greatly influenced this relationship. Immediately p. p., there was a response in the RF score of half a score with an additional intake of 3.5 kg dry matter, while a. p., a change of the PF score only occurred when the feed uptake was reduced by 18 kg dry matter. CONCLUSION: During the first week p. p., the RF score proved to be a sensitive measuring instrument for the individual feed intake. Because of its low response a. p., it was only suitable for the detection of animals at risk with a considerably reduced feed intake over several days. CLINICAL RELEVANCE: The RF score provides the most informative value during the first week p. p. to assess the increase in feed intake in the individual cow after calving. It is recommended to score the RF daily during the first 7-9 days p. p. and to evaluate it individually to detect risk animals with a reduced feed intake. During the dry period, only cows with a significantly reduced feed intake over several days can be detected and consequently treated early to prevent disorders p. p. During lactation (evaluated on days 28 and 60 p. p.), the RF score appears to be of very limited informative value regarding the individual feed intake.