Concentrate composition for Automatic Milking Systems — Effect on milking frequency

The purpose of this study was to investigate the potential of affecting milking frequency in an Automatic Milking System (AMS) by changing ingredient composition of the concentrate fed in the AMS. In six experiments, six experimental concentrates were tested against a Standard concentrate all supplied in the amounts of 5 kg/cow/day. Fifteen cows were fed the experimental concentrate and another 15 cows the Standard concentrate for 14 days and then for the next 14 days the cows were fed the opposite diets to be their own control. The change from one mixture to the next was done over only one day. In each experiment the 30 cows were composed of 12–14 of Danish Holstein, 8–10 of Danish Red and 8 were Jerseys. Basal mixed ration (MR) was fed ad libitum and intake was recorded individually. The effect of the different concentrates on intake and production was evaluated within experiment against the Standard concentrate. A marked effect was found on the number of visits of the cows in the AMS and the subsequent milk production in relation to composition of the concentrate. The composition of the concentrates also influenced the composition of the milk and the MR intake. Based on the overall responses the cows preferred a mixture containing Barley and Oats. Also Wheat based concentrate appeared to be preferred to concentrate based on Maize or Barley and the cows did not like the Fat rich or the pure Artificially dried grass concentrate used in the experiment.     

Genetic analysis on body weight at different ages in broiler chicken raised in commercial environment

A multivariate model was developed and used to estimate genetic parameters of body weight (BW) at 1–6 weeks of age of broilers raised in a commercial environment. The development of model was based on the predictive ability of breeding values evaluated from a cross-validation procedure that relied on half-sib correlation. The multivariate model accounted for heterogeneous variances between sexes through standardization applied to male and female BWs differently. It was found that the direct additive genetic, permanent environmental maternal and residual variances for BW increased drastically as broilers aged. The drastic increase in variances over weeks of age was mainly due to scaling effects. The ratio of the permanent environmental maternal variance to phenotypic variance decreased gradually with increasing age. Heritability of BW traits ranged from 0.28 to 0.33 at different weeks of age. The direct genetic effects on consecutive weekly BWs had high genetic correlations (0.85–0.99), but the genetic correlations between early and late BWs were low (0.32–0.57). The difference in variance components between sexes increased with increasing age. In conclusion, the permanent environmental maternal effect on broiler chicken BW decreased with increasing age from weeks 1 to 6. Potential bias of the model that considered identical variances for sexes could be reduced when heterogeneous variances between sexes are accounted for in the model.     

Effects of wind turbines and other physical elements on field utilization by pink-footed geese (Anser brachyrhynchus): A landscape perspective

The effects of wind turbines and other physical landscape elements on field utilization by wintering pink-footed geese (Anser brachyrhynchus) were studied in a Danish farmland landscape. Within the study area geese were feeding on pastures, which together with cereals were the main crop types. Apart from wind turbines a variety of potentially disturbing landscape elements was present, e.g., high-power lines, windbreaks, roads and settlements. Patterns of field use were assessed by measuring goose dropping densities along transects perpendicular to wind farms (with turbines in clusters and in lines) and other landscape elements. Local effects were expressed in terms of `avoidance distance', i.e., the distance from a given landscape element to the point at which 50% of maximal dropping density was reached. The spatial distribution of landscape elements within an eight km radius from the goose roost was determined from aerial photographs. The area occupied by various elements, together with the adjacent zones which were not available to geese due to their associated avoidance distances, were quantified using Geographic Information System (GIS).The avoidance distance of wind farms with turbines in lines and in clusters were ca 100 m and ca 200 m, respectively. Geese did not enter the area between turbines within the cluster. At the landscape level, the combined effect of physical elements other than wind turbines caused an effective loss of 68% of the total field area (40 km²). Wind turbines caused an additional loss of 4% of the field area. However, of the remaining area available to geese (13 km²), wind turbines caused a loss of 13% of the total area. The habitat loss per turbine was higher for the wind farm with turbines arranged in a large cluster than for wind farms with turbines in small clusters or lines. This difference was mainly due to the fact that wind farms in small clusters or with a linear layout were generally placed close to roads or other elements with existing associated avoidance zones, whereas the large cluster was placed in the open farmland area. The avoidance zones associated with physical elements in the landscape do not take into account possible synergistic effects and, hence, actual field areas affected are likely to be minimum estimates. Implications of these findings for planning of wind farms in areas of conservation interest to geese are discussed.     

Comparative bacteriological studies on summer mastitis in grazing cattle and pyogenes mastitis in stabled cattle in Denmark.

A total of 143 secretions from clinical cases of summer mastitis (SM) in grazing cattle and from 89 cases of pyogenes mastitis (PM) in stabled cattle were examined bacteriologically. The typical bacteriological finding was a mixed flora in which the predominant organisms were Actinomyces pyogenes (SM-70%, PM-85%), Peptostreptococcus indolicus (54%, 54%), a microaerophilic coccus (Stuart-Schwan coccus) (26%, 25%), Fusobacterium necrophorum biovar B (22%, 12%), Bacteroides melaninogenicus (20%, 9%) and Streptococcus dysgalactiae (21%, 5%). All except six cases occurred in non-lactating animals or within three weeks after parturition. The majority of animals (about 90%) had only one quarter affected and no differences in quarter distribution were observed between the two groups.     

Studies on microaerophilic cocci (Stuart-Schwan cocci) isolated from summer mastitis and other pyogenic infections of cattle

Forty-nine strains of microaerophilic gram-positive cocci (Stuart-Schwan cocci) isolated from summer mastitis, "pyogenes"-mastitis, other pyogenic conditions of Danish cattle and swine, and from the sheep headfly Hydrotaea irritans were biochemically characterized with the API 50 CH and API ZYM test kit systems, and screened for production of a variety of extracellular enzymes by agar plate methods. For comparison 4 strains isolated from Swedish cases of heifer and dry cow mastitis were included in the study. Similarity calculations indicated a high degree of homogeneity within the strains studied (similarity level 92%; group mean similarity 87%). The strains probably represent one species, although the taxonomic position of the organism remains unclear. The biochemical feature of the strains studied were very similar for strains isolated from cases of summer mastitis and strains from other sources of origin. It is suggested that the Stuart-Schwan coccus occurs as a natural cohabitant to Actinomyces pyogenes, Peptostreptococcus indolicus and the anaerobic organism characteristic of the bacterial complex isolated from summer mastitis and similar pyogenic conditions in ruminants and swine.     

Supplementation with sunflower seeds in beef cattle did not impact on oocyte and in vitro embryo production

Supplementation with compounds rich in linoleic acid, including sunflower seed supplementation, promotes increase in conception rates in cows. We aimed to evaluate whether the sunflower seed (linoleic acid source) supplementation in beef donor females alters the plasma concentrations of cholesterol, triglycerides, HDL and LDL, increases the number and quality of oocytes, increases the cleavage rates and determines an improvement in number and quality of in vitro produced blastocysts. Thus, Nelore females were divided into two groups of 15 animals to receive supplementation with or without sunflower seed for 57 days. Females underwent follicular aspiration and the oocytes were subjected to in vitro embryo production. There was no difference (p > .1) between control group and group supplemented with sunflower seed on the number of displayed follicles; number of aspired oocytes; recovery rate; cleavage rate; number of embryos; number of blastocysts; embryos number of grades I and II; plasma concentrations of total cholesterol, triglycerides; HDL and LDL. Therefore, sunflower seed supplementation in oocyte donors did not increase the number and quality of oocytes, cleavage rates and the number and quality of blastocysts produced in vitro.