No abstract

The objective of this study was to compare the feeding behaviour of high-yielding dairy cows in relation to parity during early to peak lactation and to determine whether or not there was any relationship between variables describing their feeding behaviour and total feed intake. Information concerning feed intake of each individual dairy cow is especially valuable for the herd management, particularly in early lactation. However, technical requirements for implementation are rarely given. Therefore, relationships between feed intake and time-related feeding behaviour parameters are of special interest. Time-related parameters could be recorded on farm conditions adapted sensor technology. Seventy high-yielding lactating dairy cows in different parities (23 in the 1st lactation, 17 in the 2nd lactation, and 30 in the 3rd-and-more-lactation) with an average of 11 000 kg milk yield per year were fed using automatic feeders from the 2nd to the 15th week of lactation. 222 231 recorded visits were analysed in three equal periods (period 1 = 7-39, period 2 = 40-72, and period 3 = 73-105 days in milk [DIM]) during early to peak lactation. Visits were clustered in meals based on the estimated meal criterion (28.5 min). The present study yielded the following values for meal frequency, number of visits per meal, meal duration, meal size, daily mealtime, daily dry matter intake (DMI), and feeding rate over the course of the study were 7.61 ± 1.7 (mean ± SD) meals/d, 4.02 ± 1.68 visits/meal, 37.07 ± 13.77 min/meal, 2.96 ± 0.92 kg DM/meal, 272.18 ± 82.14 min/d, 21.46 ± 4.29 kg DM/d, and 85.56 ± 28.77 g DM/min, respectively. Younger cows had more meals per day, more number of visits per meal, longer daily mealtime but a smaller meal size, lower daily DMI, and lower feeding rate compared to older cows (P<0.001). Meal duration and meal size were highly related to the number of visits at feeder per meal (R 2 =0.55-0.63; P<0.001, R 2 =0.25-0.39; P<0.001 respectively). In addition, meal size was highly related to meal duration (R 2 =0.59-0.72; P<0.001). Results from this study, which analysed data based on meal criterion, showed a higher correlation between the selected parameters of feeding behaviour and feed intake. The high correlation between meal duration and meal size could be used to estimate feed intake.Keywords: feeding behaviour, feed intake, parity, dairy cow

Fourteen pairs of identical female Holstein twins were used for a feeding trial during a period between 3 rd and 21 st month. One in two sibling was reared continuously at a medium (M) and the other one at a high (H) feeding intensity. Lasting diet effects of body weight (BW), back fat thickness (BFT), and milk performance (M-kg) were analyzed for the subsequent lactation. A lasting diet effect was verifiable for BFT, whereas BW don't differ between groups. BFT indicated the changes from negative to positive energy balance 7 and 10 weeks later than BW, for M and H group, respectively. Besides, BFT showed, that the duration and dimension of negative energy balance was longer in H group than in M group. BFT difference became smaller according day of lactation and resulted in about zero at day 305 of lactation. If the groups were compared only by feeding intensity, the daily milk yield was 1.7 kg higher in M than in H group, but the difference didn't show any significance (p=0.22). However, the tendency of superiority was completely absorbed after the addition of the covariate age at first calving (AFC) in the model. Presented date in identical twins give no indications for lasting feeding effects per se on milk performance. Introduction Feeding during rearing period does not only influence the growth rates of calves and heifers. Some researchers also reported evidences for lasting effects on performance in lactating dairy cows, especially, when the feeding concerned the prepubertal period of development (SJERSEN and PURUP, 1997;VAN AMBURGH et al., 1998). In these investigations a moderate feeding level was beneficially for lactational performance. Although the physiological reasons of feeding effects on milk performance are not well defined, there are evidences suggest that the composition of the mammary gland and differences in hormonal patterns could be involved (SJERSEN and PURUP, 1997; SJERSEN et al., 2000). On the other hand, other researches found no differences in milk production, when heifers were fed at a moderate or high feeding level (ABENI et al., 2000;ABENI et al., 2003) and results of CAPUCO et al. (1995) did not show an influence of udder composition on milk performance. According results of LACASSE et al. (1993), MÄNTYSAARI et al. (1999), andMÄNTYSAARI et al. (2002), the responsiveness of milk performance according to feeding after puberty and during gestation seems to be anymore inconsistently. Possible reasons for this contrariness could be the varieties of investigation conditions like diet, ontogentic location and length of the treatment period. Additionally, also the use of animals, which have different genetic potential for yield or for responsiveness after feeding stimuli, could be induce inconsistent results, especially in small samples. Differences in body condition and changes of body condition also could lead to varieties in milk yield and animals health, even when body weight is the same. Like shown by VAN AMBURGH et al. (1998) heifers, fed diet formulated to an high average dai...

In studies with weaned piglets of the land race the usability of partly hydrolysed straw meal (PSM) in concentrate - straw meal mixtures was tested over a period of 56 days (42nd-98th day of life; 1st-8th week of feeding. The hydrolysed straw product was there tested in a parallel experiment each without and after neutralization (by means of CaCO3) in quotas of 5, 10 and 15% as supplement to the concentrate feed (based on dry matter) in comparison to a sole concentrate feeding. Daily weight gain and feed and energy expenditure as well as nutrient digestibility and the buffer effect of the PSM rations were ascertained. Measured by weight gain, feed intake and concentrate- and energy expenditure related weight gain, a 10% quota of partly hydrolysed straw meal in a period near weaning (1st-4th week of feeding) had the highest effect and was far superior to traditional concentrate feeding. Lower quotas of PSM in this period did not show a sufficient dietetic effect (diarrhea symptoms), higher reduced the effect on the performance parameters. In the period more remote from weaning (5th-8th week of feeding) the effect of the straw meal integration was generally reduced, a quota of about 5% proved optimal. The registered higher daily weight gains in the total test period (1st-8th week of feeding in which concentrate - straw meal mixtures (relative 106-130%) were closely related to the daily intake of digestibility organic matter. The decrease in digestibility of organic matter in the total ration remained small with the use of the well fermentable crude fibre from the hydrolysed straw product and the balance was overcompensated by higher feed intake. A pH-value decrease of the feed mixtures and a physiologically suitable influence on the pH-value in the stomachs of the test animals could be ascertained due to the buffer capacity of the hydrolysed straw products used. With regard to this, the non-buffered hydrolysed straw product had a higher effect, which was, among other things, reflected in higher performances.

No abstract