Variability in individual animal's intake of minerals offered free-choice to grazing ruminants

A review of the literature indicates that there is very little published information on the variation in intake of minerals and other supplements offered free-choice to grazing animals. Most of the studies have been conducted with molasses feedblocks and liquid licks and the data indicate large day to day and among animal variation. A computer recording system has been developed and tested which allows for more information to be collected with regard to frequency of consumption of free-choice supplements by grazing animals. Studies have been conducted with molasses blocks and loose mineral supplements provided to grazing cattle. Results indicate that the supplements were consumed by almost all animals on a regular basis. However, there was considerable variation among animals in the quantity of supplement consumed. For the molasses blocks daily intake averaged 1.2 ± 0.6 kg per head within a range of 0.72–1.65 kg. For the mineral supplement the average daily consumption was 135 ± 55 g per head within a range of 50–300 g. The supplement feeders were visited every hour of the day but approximately 40% of the visits occurred in the late evening. Information on the behavioural pattern of consumption may enable strategies to be developed which could reduce the variation in consumption.     

Evaluation of trace element status of organic dairy cattle

The present study aimed to evaluate trace mineral status of organic dairy herds in northern Spain and the sources of minerals in different types of feed. Blood samples from organic and conventional dairy cattle and feed samples from the respective farms were analysed by inductively coupled plasma mass spectrometry to determine the concentrations of the essential trace elements (cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), iodine (I), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se) and zinc (Zn)) and toxic trace elements (arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb)). Overall, no differences between organic and conventional farms were detected in serum concentrations of essential and toxic trace elements (except for higher concentrations of Cd on the organic farms), although a high level of inter-farm variation was detected in the organic systems, indicating that organic production greatly depends on the specific local conditions. The dietary concentrations of the essential trace elements I, Cu, Se and Zn were significantly higher in the conventional than in the organic systems, which can be attributed to the high concentration of these minerals in the concentrate feed. No differences in the concentrations of trace minerals were found in the other types of feed. Multivariate chemometric analysis was conducted to determine the contribution of different feed sources to the trace element status of the cattle. Concentrate samples were mainly associated with Co, Cu, I, Se and Zn (i.e. with the elements supplemented in this type of feed). However, pasture and grass silage were associated with soil-derived elements (As, Cr, Fe and Pb) which cattle may thus ingest during grazing.     

Trace Mineral Micronutrients and Chronic Periodontitis—a Review

Trace mineral micronutrients are imperative for optimum host response. Populations worldwide are prone to their insufficiency owing to lifestyle changes or poor nutritional intake. Balanced levels of trace minerals like iron (Fe), zinc (Zn), selenium (Se) and copper (Cu) are essential to prevent progression of chronic conditions like periodontitis. Their excess as well as deficiency is detrimental to periodontal health. This is specifically true in relation to Fe. Furthermore, some trace elements, e.g. Se, Zn and Cu are integral components of antioxidant enzymes and prevent reactive oxygen species induced destruction of tissues. Their deficiency can worsen periodontitis associated with systemic conditions like diabetes mellitus. With this background, the present review first focusses on the role of four trace minerals, namely, Fe, Zn, Se and Cu in periodontal health followed by an appraisal of the data from case control studies related to their association with chronic periodontitis.     

Biofortifying crops with essential mineral elements

Humans require more than 22 mineral elements, which can all be supplied by an appropriate diet. However, the diets of populations subsisting on cereals, or inhabiting regions where soil mineral imbalances occur, often lack Fe, Zn, Ca, Mg, Cu, I or Se. Traditional strategies to deliver these minerals to susceptible populations have relied on supplementation or food fortification programs. Unfortunately, these interventions have not always been successful. An alternative solution is to increase mineral concentrations in edible crops. This is termed 'biofortification'. It can be achieved by mineral fertilization or plant breeding. There is considerable genetic variation in crop species that can be harnessed for sustainable biofortification strategies. Varieties with increased mineral concentrations in their edible portions are already available, and new genotypes with higher mineral densities are being developed.     

Increasing the number of plant species in a pasture improves the mineral balance of grazing beef cattle

Because of the essential role of minerals in maintaining homeostasis in large herbivores, a dietary intake that avoids deficiency or excess is crucial to keeping animals healthy. However, mineral element concentrations are highly variable between and within plant species. We therefore hypothesized that the mineral balance in grazing cattle may be influenced by plant species abundance in pasture. We simulated mineral intakes using two different models (algorithms) for varying numbers of 17 plant species characterized in a field survey of a temperate pasture in Japan. We calculated the mineral intakes from 1000 combinations of species for each species richness (number of species) for each of 12 mineral elements. Both models indicated that the estimated intakes of Mg, K and Mn could exceed the maximum tolerable range, and those of P, Na, Fe and Cu could potentially fail to meet the minimum requirements. The mean proportion of estimated intakes that ranged between minimum requirement and maximum tolerable level was approximately 17% higher for 17 species than for a single species. These results suggest that increasing the plant diversity in the pasture reduced the risk of mineral deficiencies or toxicities. Our results indicate that wild plants, normally regarded as weeds, should be maintained within improved pasture to maintain species diversity and assist with the mineral balance of animals grazed upon it. This work is an important precursor to future studies linking animal husbandry and ecological research.     

Mineral and heavy metal status as related to a mortality event and poor recruitment in a moose population in Alaska

Moose (Alces alces) found dead (FD) and hunter-killed (HK) in 1995 on the north slope of Alaska (USA) in the Colville River Drainage were evaluated for heavy metal and mineral status. Compared to previous reports for moose and domestic cattle, and data presented here from Alaska moose outside the Colville River area, levels of Cu were determined to be low in hoof, hair, liver, kidney, rumen contents, and muscle for these north slope moose. Iron (Fe) was low in muscle as well. These findings, in conjunction with evidence of poor calf survival and adult mortality prompted investigation of a mineral deficiency in moose (serum, blood, and hair) captured in the spring of 1996 and 1997. Captured males had higher Ca, Zn and Cu levels in hair than captured females. Female moose hair samples were determined to be low (deficient) in Cu, Ca, Fe, and Se with mean levels (ppm) of 2.77, 599.7, 37.4, and 0.30, respectively. Serum Cu level was low, and to a lesser degree Zn was deficient as well. Whole blood (1997 only) was marginally deficient in Se and all animals were deficient in Cu. Based on whole blood, sera and hair, Cu levels were considered low for moose captured in spring 1996 and 1997 in the Colville River area as compared to published data and other populations evaluated in this study. Low levels of ceruloplasmin activity support this Cu deficiency theory. Evidence indicates that these moose are deficient in Cu and other minerals; however, the remote location precluded sufficient examination of animals to associate this apparent deficiency with direct effects or lesions. Renal levels of Cd increased with age at expected levels.     

Superoxide dismutase and glutathione peroxidase activities in neutrophils from selenium deficient and copper deficient cattle

Oxygen consumption and the activities of the selenoenzyme glutathione peroxidase, and of the hexose monophosphate shunt were lower than normal in neutrophils from Se deficient cattle. However, these activities and the activity of Cu/zinc superoxide dismutase were unaffected in neutrophils from Cu deficient cattle. These results are discussed with reference to impaired neutrophil microbicidal activity previously demonstrated to result from Se or Cu deficiency in cattle.     

Net mineral requirements for the growth and maintenance of Somali lambs

Minerals are limiting factors in animal production, and the knowledge of mineral requirements for livestock is crucial to the success of a commercial enterprise. Hair sheep may have different mineral requirements than those presents by the international committees. A study was carried to evaluate the net calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K), zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu) requirements for the growth and maintenance of Brazilian Somali lambs. A total of 48 hair lambs (13.5±1.8 kg) aged 60±15 days were allocated to individual pens. Eight animals were slaughtered at the beginning of the experiment to serve as a reference group to estimate initial empty BW (EBW) and initial body composition. The remaining lambs (n=40) were assigned to a completely randomized design with eight replications in five levels of metabolizable energy (ME; 4.93, 8.65, 9.41, 10.12 and 11.24 MJ/kg DM). When the lambs of a given treatment reached an average BW of 28 kg, they were slaughtered. Initial body composition was used to calculate the retention of minerals. Mineral body composition was fit using a logarithmic equation in the form of a nonlinear model. The maintenance requirements were estimated from regressions of mineral retention in the empty body on mineral intake. The body mineral concentration decreased in lambs with a BW ranging from 15 to 30 kg. The net mineral requirements (100 g/day of average daily gain (ADG)) decreased from 0.52 to 0.51 g for Ca, 0.28 to 0.23 g for P, 0.02 to 0.02 g for Mg, 0.09 to 0.08 g for Na, 0.11 to 0.09 g for K, 1.30 to 1.08 mg for Zn, 3.77 to 3.22 mg for Fe, 0.08 to 0.06 mg for Mn and 0.09 to 0.08 mg for Cu when BW increased from 15 to 30 kg. The daily net requirements for maintenance per kilogram of BW were 30.13 mg of Ca, 27.58 mg of P, 1.26 mg of Mg, 4.12 mg of Na, 8.11 mg of K, 0.133 mg of Zn, 0.271 mg of Fe, 0.002 mg of Mn and 0.014 mg of Cu. The results of this study indicate that the net mineral requirements for weight gain and maintenance in Brazilian Somali lambs are different than the values that are commonly recommended by the main evaluation systems for feed and nutritional requirements for sheep. These results for the nutritional requirements of minerals may help to optimize mineral supply for hair sheep.     

Mineral status in selenium-deficient rats compared to selenium-sufficient rats fed vitamin-free casein-based or torula yeast-based diet

To clarify the mineral status in selenium (Se)-deficient rats fed a vitamin-free casein (VFC)-based or torula yeast (TY)-based diet, 24 weanling male Wistar rats were divided into 4 groups fed diets using VFC or TY as the protein source and containing Se at sufficient (0.5 μg/g,⁺Se) or deficient (0.019 μg/g for VFC-based and <0.005 μg/g for TY-based diets,⁻Se) level for 8 wk. TY supplied a larger amount of extra minerals (Na, K, Ca, Mg, Fe, Mn, Zn, and Cu) except Se than VFC. Se concentration and glutathione peroxidase activity were significantly lower in TY-fed rats than in VFC-fed rats, as well as in⁻Se rats compared to⁺Se rats. Compared to⁺Se rats, Fe concentration was higher in liver and muscle of⁻Se rats fed the VFC-based diet and in plasma, heart, liver, and tibia of⁻Se rats fed the TY-based diet. Compared to⁺Se rats, decreases of Mn concentration appeared in plasma, heart, and tibia of VFC-fed⁻Se rats and in brain, heart, liver and tibia of TY-fed⁻Se rats. There was also a little imbalance in Ca, Mg, Na, K, and Cu caused by Se deficiency. The results indicated that Se deficiency induced the mineral imbalance in rats, especially an increase in Fe and decrease in Mn, which was more severe in TY-fed rats than VFC-fed rats. However, TY cannot be used as a model for both Se and other mineral deficiency because of the extra minerals except Se found in TY. Instead, VFC can be employed, which contains fewer minerals except Se than TY and also can produce a severe degree of Se deficiency.     

Effects of Added CeCl<Subscript>3</Subscript> on Resistance of Fifth-Instar Larvae of Silkworm to <Emphasis Type="Italic">Bombyx mori</Emphasis> Nucleopolyhedrovirus Infection

The aim of this study was to investigate the influence of mineral sources on broiler breeders and their offsprings. Broiler breeding hens were fed with diets containing either organic or inorganic trace minerals at equal levels, i.e., (1) control group was fed with basal diet supplemented with inorganic trace minerals; (2) OZ group was fed with organic Zn instead of sulfate; and (3) OTM group was fed with organic Cu, Mn, Zn, and Se instead of inorganic sources. Results indicated that OTM supplementation decreased plasma cholesterol and triglyceride and increased yolk triglyceride via increasing high-density lipid protein cholesterol and decreasing low-density lipid protein cholesterol and very low-density lipid protein (VLDL) in plasma. OZ diets decreased plasma cholesterol and triglyceride mainly by reducing VLDL concentration. For control group, increased lipid concentrations resulted in increased lipid peroxidation in serum and malondialdehyde retention in yolk. Zn retention was not affected. Otherwise, OZ diet was observed to decrease Cu in yolk and albumen. While for OTM group, albumen Cu, albumen Se, and hepatic Se of hatched chicks were increased, but yolk Cu was decreased. Moreover, organic mineral supplementations improved broilers’ growth performance. In conclusion, organic mineral supplementation in breeders’ diets protected breeders from lipid peroxidation, increased egg nutrition retention, and benefit for growth of broilers.     

Mineral concentrations in serum/plasma and liver tissue of captive and free‐ranging Rhinoceros species

Mineral implications in health issues of captive rhinos have received much attention lately. This study was undertaken to establish reference values for the mineral status of rhinos. Serum/plasma samples of free‐ranging black (Diceros bicornis) and white (Ceratotherium simum) rhinos and of captive black, white, Indian (Rhinoceros unicornis), and Sumatran (Dicerorhinus sumatrensis) rhinos, as well as liver tissue samples of captive black, white, and Indian rhinos were analyzed for mineral content. Circulating mineral levels of free‐ranging animals were subject to variation according to region. In free‐ranging animals, high molybdenum (Mo) values compared to horse normals were striking. Captive animals displayed even higher circulating Mo concentrations. The significance of iron (Fe) overload in captive specimens of the browsing rhinos (black and Sumatran) was confirmed. Hepatic Fe levels increased in blacks with age. Although this Fe overload is suspected to be linked with diets, the data indicate that this is not due solely to an excessive dietary Fe supply. Whereas the grazing species (white and Indian) had high liver copper (Cu) levels, the browsing species had low to marginal liver Cu concentrations. Liver concentrations of K, Mg, Co, and Mo increased with age in captive black rhinos. Additional findings include high circulating Se levels in all rhino species. Future research should be directed at investigating factors leading to high Fe levels, and at investigating Cu metabolism in captive rhinoceros species. Zoo Biol 24:51–72, 2005. © 2005 Wiley‐Liss, Inc.     

Effect of Organic Zinc,Manganese, Copper,and Selenium Chelates on Colostrum Production and Reproductive and Lameness Indices in Adequately Supplemented Holstein Cows

The current study aimed to investigate if different sources of supplemental zinc (Zn), manganese (Mn), copper (Cu), and selenium (Se) fed to dry and lactating dairy cows affect reproductive performance, lameness status, and colostrum production. The experiment was carried out on 60 multiparous non-lactating Holstein cows in a commercial dairy herd. The cows received randomly mineral mixtures in three treatment groups containing inorganic, 25% organic–75% inorganic, or 50% organic–50% inorganic forms of Zn, Mn, Cu, and Se starting from approximately 3 weeks prior to calving up to 90 days postpartum. Supplements were included in rations and fed twice a day. Reproductive parameters including days to first service, days to first estrus, service per conception, and conception rate were investigated. After parturition, colostrum production, composition, and immunoglobulin G₁ concentration were determined. Lameness, as an indicator of trace minerals deficiency, was evaluated in a five-score scale. The source of mineral supplement only numerically improved the assessed parameters excluding colostrum fat, protein, and ash percent. The organic form of supplements did not significantly affect reproductive performance, lameness score, or colostrum production.     

Global Patterns and Trends for Non‐Metallic Minerals used for Construction

Despite accounting for almost 50% of global material use, nonmetallic minerals—mostly used for construction of buildings and infrastructure—are the material flow analysis (MFA) category with the highest uncertainty. The main reason for this is incomplete reporting in official national statistics because of ease of availability and the low per‐unit cost of these materials. However, the environmental burden associated with nonmetallic minerals, which include energy use for extraction and transport, land‐use change, and disposal of large amounts of construction demolition waste, call for a thorough understanding of the magnitude of nonmetallic mineral flows. Previous estimates for nonmetallic minerals have used simplistic assumptions. This study aims to increase the precision of nonmetallic mineral accounts at national and global level using consumption of bitumen, bricks, cement, and railways in combination with technical coefficients from the engineering literature to infer the actual yearly consumption of nonmetallic minerals. We estimate the extraction of nonmetallic minerals and provide uncertainty estimates for the new accounts as well as information about consumption by different sectors. Analyzing the evolution of consumption for seven world regions, we find that, in North America and Europe, the consumption of nonmetallic minerals over the past 40 years has followed the growth patterns of population, whereas for all other regions consumption has been closely related to gross domestic product (GDP). A more accurate account of global and country‐by‐country extraction of nonmetallic minerals may provide insights into supply shortages and inform waste management strategies for construction and demolition waste.     

Phosphorus nutrition of grazing cattle: a review

Phosphorus (P) is a widely studied element which is integral to many vital body functions. In ruminant nutrition, however, the degree of naturally occurring P deficiency in grazing cattle, the lack of uniformity in response to P supplementation, and even suggested P requirements have generated a great deal of confusion in the United States and around the world. Much of the confusion arises because animals have the ability to draw on skeletal P reserves when dietary P levels are inadequate. The mechanisms that control skeletal P withdrawal, the conditions that trigger withdrawal, and the rate and extent of withdrawal without affecting animal performance seem to be poorly understood. Another area of confusion involves the detrimental effect of P deficiency on feed intake which makes it unclear in many situations whether animal responses to P supplementation are due to P per se or simply to increased feed intake. This review attempts to discuss these and other important problems concerning the P nutrition of grazing cattle.     

Hepatic minerals of white-tailed and mule deer in the southern Black Hills, South Dakota

Because there is a paucity of information on the mineral requirements of free-ranging deer, data are needed from clinically healthy deer to provide a basis for the diagnosis of mineral deficiencies. To our knowledge, no reports are available on baseline hepatic mineral concentrations from sympatric white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) using different habitats in the Northern Great Plains. We assessed variation in hepatic minerals of female white-tailed deer (n = 42) and mule deer (n = 41). Deer were collected in February and August 2002 and 2003 from study areas in Custer and Pennington Counties, South Dakota, in and adjacent to a wildfire burn. Hepatic samples were tested for levels (parts per million; ppm) of aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), boron (B), cadmium (Cd), calcium (Ca), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), magnesium (Mg), manganese (Mn), mercury (Hg), molybdenum (Mo), nickel (Ni), phosphorus (P), potassium (K), selenium (Se), sodium (Na), sulfur (S), thalium (Tl), and zinc (Zn). We predicted that variability in element concentrations would occur between burned and unburned habitat due to changes in plant communities and thereby forage availability. We determined that Zn, Cu, and Ba values differed (P 相似文献   

Selenium and sulfur supplementation to steers grazing tall fescue

Forty steer calves averaging 257 kg were allotted to a randomized complete block design experiment containing 10 animals per treatment. Four tall fescue pastures of 5.7 ha each were utilized during the 84-d grazing study. Each pasture treatment block contained 10 calves. Calves were fed a control supplement of 96.9% ground corn and 3.1% trace mineral salt in two pastures, or a sulfur supplement that contained 94.3% ground corn, 3.1% trace mineral salt, and 2.5% elemental sulfur in the remaining two pastures. Each supplement was fed at the rate of 0.45 kg/head daily. One-half of the calves in each pasture were injected with 15 mg selenium (Se) as sodium selenite initially and at 28-d intervals throughout the trial. The treatments were as follows: (1) control-no sulfur, no selenium; (2) selenium, no sulfur; (3) sulfur, no selenium and; (4) selenium plus sulfur. Calf weights were monitored and certain blood parameters measured every 28 d. Average plasma Se values were increased (P < 0.001) from 0.021 ppm in calves not receiving Se to 0.043 ppm in those receiving Se. Plasma urea nitrogen levels were not affected by Se administration, but were lowered (P <0.05) from 16.6 to 15.8 mg/100 mL by sulfur administration. All plasma amino acids measured, except methionine, phenylalanine, argi-nine, and citrulline, were cleared from the blood in response to Se supplementation as reflected by their lower concentrations when compared with other treatment groups. Overall average daily gains were not significantly (P > 0.10) increased by sulfur supplementation, but were increased (P < 0.05) from 0.33 kg/d in calves not receiving Se to 0.43 kg/d in those receiving Se injections. Significant interactions between fulfur and Se were not noted.     

Mineral Concentrations in Hair of Belgian Elementary School Girls: Reference Values and Relationship with Food Consumption Frequencies

Although evidence suggests that hair elements may reflect dietary habits and/or mineral intake, this topic remains controversial. This study therefore presents age-specific reference values for hair concentrations of Ca, Cu, Fe, Na, Mg, P and Zn using the LMS method of Cole, and investigates the relationship between dietary habits (i.e. food consumption frequencies) and hair mineral concentrations in 218 Belgian elementary school girls by reduced rank regression (RRR). Hair minerals were quantitatively determined via inductively coupled plasma?Cmass spectrometry after microwave-assisted acid digestion of 6-cm long vertex posterior hair samples. The Children??s Eating Habits Questionnaire??Food Frequency Questionnaire was used to obtain information on food consumption frequency of 43 food items in the month preceding hair collection. The established reference ranges were in line with data for other childhood or adolescent populations. The retained RRR factors explained 40, 50, 45, 46, 44 and 48?% of the variation of Ca, Cu, Fe, Mg, P and Zn concentrations in hair, respectively. Although this study demonstrated that a large proportion of hair mineral variation may be influenced by food consumption frequencies in elementary school girls, a number of food groups known to be rich sources of minerals did not show a relation with certain hair minerals. Future research should focus on mechanisms and processes involved in mineral incorporation and accumulation in scalp hair, in order to fully understand the importance and influence of diet on hair minerals.     

Effects of Mineral Structure and Microenvironment on K Release from Potassium Aluminosilicate Minerals by Cenococcum geophilum fr

K-bearing minerals with enormous reserve in the world, were not easy to provide the available K nutrient element for plant direct uptake because of the slow K release rate. With the potential potassium-solubilizing microorganisms, the slow K release rate from minerals would be improved significantly. In this work, Cenococcum geophilum Fr, one of the most common ectomycorrhizal fungi in boreal to temperate regions, was adopted to dissolve K-bearing minerals for K release. Five kinds of potassium aluminosilicate minerals were tested by bioleaching experiments in pure culture, including feldspar, nepheline, biotite, muscovite and illite. The available and unavailable potassium amounts in minerals before and after bioleaching were measured and compared with each other. The effect of mineral structure on the potassium solubilization efficiency by Cenococcum geophilum Fr. was discussed. Furthermore, the microenvironment formation between fungi and mineral surface to enhance the K release rate was investigated through detecting K, Al, Si concentrations and metabolites amounts (polysaccharide and organic acids) in microenvironment and external environment, respectively. Experimental results demonstrated that Cenococcum geophilum Fr. was a potential candidate of potassium solubilizing microorganisms, and both mineral structure and microenvironment have significant effects on the K release rate.     

Analysis of Human Serum and Whole Blood for Mineral Content by ICP-MS and ICP-OES: Development of a Mineralomics Method

Minerals are inorganic compounds that are essential to the support of a variety of biological functions. Understanding the range and variability of the content of these minerals in biological samples can provide insight into the relationships between mineral content and the health of individuals. In particular, abnormal mineral content may serve as an indicator of illness. The development of robust, reliable analytical methods for the determination of the mineral content of biological samples is essential to developing biological models for understanding the relationship between minerals and illnesses. This paper describes a method for the analysis of the mineral content of small volumes of serum and whole blood samples from healthy individuals. Interday and intraday precision for the mineral content of the blood (250 μL) and serum (250 μL) samples was measured for eight essential minerals—sodium (Na), calcium (Ca), magnesium (Mg), potassium (K), iron (Fe), zinc (Zn), copper (Cu), and selenium (Se)—by plasma spectrometric methods and ranged from 0.635 to 10.1 % relative standard deviation (RSD) for serum and 0.348–5.98 % for whole blood. A comparison of the determined ranges for ten serum samples and six whole blood samples provided good agreement with literature reference ranges. The results demonstrate that the digestion and analysis methods can be used to reliably measure the content of these minerals and potentially of other minerals.     

Reactions to saline drinking water in Boer goats in a free-choice system

Salinization of groundwater and soil is a prevalent global issue with serious consequences on animal health and production. The present study was conducted to investigate the capacity of Boer goats to adjust their salt intake from saline drinking water in a free-choice system. In total, 12 non-pregnant Boer goats aged between 1 and 8 years with an average BW of 46.4±8.3 kg were kept in individual pens for 4 weeks. In the control phase (1 week), only fresh water was supplied in five identical buckets for each pen. During the subsequent treatment phase (3 weeks), fresh water and four different concentrations (0.75, 1.0, 1.25 and 1.5% NaCl) of saline water were offered simultaneously in a free-choice system. The positions of the concentrations were changed daily at random. Cut hay and water were provided ad libitum, and a mineral supplement was allocated. Feed and water intake, mineral supplement intake, ambient temperature and relative humidity were recorded daily, whereas BW and body condition score were measured weekly. Dry matter intake, total water intake and total sodium intake were significantly (P<0.001) higher during the treatment phase. Body weight and body condition were not affected by saline water intake. Across the treatment phase, saline water consumption was significantly (P<0.001) lower in young (19.6±27.1 g/kg BW^0.82 per day) than in adult goats (27.9±31.5 g/kg BW^0.82 per day), indicating that young goats were more sensitive towards the saline water. All goats had a significant preference for fresh water (0% salt) over saline water. At the first offering of the simultaneous choice situation (week 2), animals did not differentiate between the salt concentration of 0.75% and 1.0%. However, with successive treatment (weeks 3 and 4), animals distinguished between saline water concentrations and preferred the 0.75% salt concentration. Salt concentrations of 1% to 1.5% were avoided. The total sodium intake of the goats ranged between 0.37 and 0.55 g /kg BW^0.75 per day during the treatment phase, being 8- to 11-fold higher than the daily requirements of sodium for body maintenance. The results suggest that goats are able to differentiate between saline water concentrations and to adjust their sodium intake by quick adjustments in self-selection in a free-choice system. Compared with two-choice preference tests, the present free-choice situation allows evaluating changes in saline water acceptance with prolonged exposure.