Epsilon Archive for Student Projects

Abstract

The aim of the study was to investigate the practical experiences and potential of using water from the Baltic Sea as drinking water for cattle and its immediate effects on health, and growth. Two studies were performed: one farmer survey and one experimental grazing study. Eighteen farmers along the Baltic coast with animals grazing near the Baltic Sea were interviewed about their experiences of having cattle drink from the Baltic Sea. The experimental study lasted 104 days in Swedish summer conditions and included 10 Hereford cows with calves and 10 Angus cows with calves, that were randomised onto Baltic Sea as their only source of drinking water (BALT), or fresh water from a trough (CON). Spatial position and insect discomfort was observed through direct observations, and potential effects of gastrointestinal function were assessed by measuring growth, faecal dry matter content and texture. Sampling also included pasture and water, and the use of a salt lick was quantified. Surveyed farmers reported positive experiences with having animals grazing nearby and drinking water from the Baltic Sea, noting benefits such as cooling, reduced insect pressure, and labour savings, while expressing some concerns about water quality and hygiene. The grazing study, did not find differences in growth performance (BALT 102 ± 28 kg vs CON 110 ± 22 kg; p=0.244), faecal dry matter (calves BALT 0.17 ± 0.02 vs. CON 0.16 ± 0.02 kg; p = 0.13 and cows BALT 0.13 ± 0.01 vs. CON 0.13 ± 0.01 kg; p = 0.11), or average faecal consistency on calves (BALT 4.5 ± 0.7 vs. CON 4.5 ± 0.7; p = 0.5). Faecal consistency was showing significant differences on cows (BALT 2.9 ± 0.9 vs. CON 3.4 ± 1.1; p = 0.04). Heat stress related behaviours showed no significant differences between treatment groups (Tail wagging p = 0.108 and head throwing p = 0.125). Water analyses and literature review indicated that salinity and trace elements remained below thresholds harmful to livestock and in most cases for human consumption. Salt block intake was lower in the BALT group than in the CON (p = 0.02). Based on estimated mineral intake from salt blocks, pasture, and water, BALT group showed lower intake of zinc, manganese, copper, iodine, selenium, and cobalt compared to NASEM recommendations. The CON group displayed a similar pattern for the trace elements, with additionally lower estimated intake of magnesium. Results suggests that Baltic Sea water is at least as safe as supplementary resource for cattle as the water given to CON group. These findings suggest that Baltic Sea water may be a safe supplementary resource for cattle during parts of the year, but further research is required to evaluate long-term safety, optimal management, and mineral supplementation strategies. Threshold values of levels safe for animal consumption should be established to easier evaluate alternative water sources for animals.