Effect of water restriction on drinking behaviour and water intake in German black-head mutton sheep and Boer goats

The present study was conducted to evaluate and compare the physiological responses of sheep and goats to water restriction using the deuterium dilution technique (D2O) to predict the total water intake (TWI) in both species. In two consecutive trials, 10 non-lactating Boer goats and 10 non-lactating German black-head mutton ewes were each randomly allocated into a treatment and a control group. In the control groups (n = 5, for each species), water was offered ad libitum, whereas the treatment groups (n = 5, for each species) received water 3 h/day on experimental days 8 to 14 and 6 h every 2 days on experimental days 15 to 22. The respiratory rate, rectal temperature, body mass and drinking behaviour were also recorded. The TWI was estimated by D2O for each animal. Water restriction for 21 h/day or 42 h/2 days had no significant (P > 0.05) effect on water intake (WI), feed intake, WI to dry matter intake ratio or body mass in both species. The absence of differences between species in their WIs was also confirmed using D2O. However, sheep had higher respiratory rates and rectal temperatures than goats in both control and treatment groups. Both species showed the ability to tolerate a moderate water shortage by activating several physiological mechanisms and behavioural strategies.     

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.     

Adaptation capacity of Boer goats to saline drinking water

Due to global climatic changes, water and soil salinization is an increasing worldwide phenomenon, thus creating new threats for farm animal production. The present study was designed to investigate the adaptation capacity of goats towards sodium chloride (NaCl) in drinking water. Twelve non-pregnant Boer goats with an average body weight of 50.5 ± 9.0 kg were kept in individual pens. The study was conducted in four phases applying a two-choice preference test. In the control phase (phase 1) only fresh water was supplied in two containers. In phase 2, water with different salt concentrations (0.25%, 0.5%, 0.75%, 1.0%, 1.25% and 1.5%) was offered in one container and tap water in the other (sensitivity test). During the third phase (adaptation), goats were stepwise habituated to saline water by offering only saline water with different increasing concentrations (between 0% and 1.5% NaCl) in both containers. Subsequently, in phase 4 (sensitivity re-test) the same treatment as in phase 2 was repeated. Goats had ad libitum access to hay, water and a mineral licking block. Individual water and feed intake were recorded daily, while body weight and body condition score were measured every 2^nd week. Body weight was not affected by saline water intake, whereas dry matter intake and body condition scores decreased significantly during the experiment. Water intake was significantly (P<0.001) higher in phase 2 (sensitivity test) and phase 3 (adaptation), compared to phase 1 (control) and phase 4 (sensitivity re-test). Total sodium intake followed the same pattern. In phase 2, when goats had the choice between fresh and saline water for the first time they preferred higher salt concentrations and consumed significantly (P<0.001) higher amounts of saline water (75.4 ± 53.2 g/kg BW^0.82 per day) than in the re-test (40.4 ± 34.0 g/kg BW^0.82 per day) after the habituation period. Thus, salt discrimination rejection thresholds were lowered to 1.25% in phase 4 compared to 1.5% in phase 2. The results suggest that a stepwise adaptation to saline drinking water in goats is an effective method to habituate the animals to saline water intake when concentrations were below 1.5%. Goats reacted more sensitively to the salinity of drinking water after prolonged exposure to saline water indicating flexible regulation mechanisms depending on the total sodium balance of the animal.     

Lactation in the tammar wallaby (Macropus eugenii). I. Milk consumption and the algebraic description of the lactation curve

The milk intake of suckling tammar wallabies ( Macropus eugenii ) was estimated between 213 and 339 days of age using a double-isotope procedure in which tritiated water (TOH) was injected into the dams and deuterium oxide (D₂O) injected into the offspring. Recycling of isotopes between mothers and offspring was shown not to be a significant source of error. Estimates of body water (isotope dilution space) in the mothers or offspring, as a proportion of their body weight, were similar to values obtained with other macropodids and with placental mammals (0.73–0.75). Total water inflow in the offspring increased throughout the period, but the proportion of this contributed by milk fell in sigmoid fashion from 95.6% at 213 d to 3.7% at 340 d. Milk intakes reached a peak of about 86 ml/d, which was low compared with placental species. Before the peak, intakes were more closely related to body weight than age. Peak milk intake corresponded with the period of emergence from the pouch. Milk intakes were also in excellent agreement with published data obtained earlier in lactation, in animals drawn from the same population. These data were therefore combined to provide estimates of intake for the whole of lactation in the tammar wallaby, and algebraic models fitted to describe the pattern of milk intake in relation to body weight or age. With body weight, the pattern of milk intake was well described by a rising linear phase to a peak intake of about 86 ml/d near 1110 g body weight, followed by a gradual exponential decline. When related to age, the pattern was well described by a rising logistic phase (peak at 251 d) followed by a sharp exponential decline. It is shown that this latter pattern is markedly similar to the shape of the functions describing the energy requirements for the sum of pregnancy and lactation in a placental species, the sheep.     

The effect of physiological state (lactating or dry) and sward surface height on grazing behaviour and intake by dairy cows

The effect of physiological state lactating vs. non-lactating (dry) on grazing behaviour and herbage intake by Holstein-Friesian cows was examined on grass pastures maintained at 5, 7 or 9 cm sward surface height (SSH), typical of those provided under continuous variable stocking management. Intake rates were estimated over periods of 1 h by weighing the animals before and after grazing, retaining the faeces and urine excreted, and applying a correction for insensible weight loss. Grazing behaviour during these periods and over 24 h was recorded automatically using sensors to measure jaw movements. Bite mass (BM) did not differ significantly between lactating and dry cows but decreased (P<0.001) from 0.42 to 0.30 g organic matter (OM) bite⁻¹ as overall mean SSH decreased from 9 to 5 cm. An increase (P=0.040) in grazing jaw movement (GJM) rate, from 75.3 to 80.3 GJM min⁻¹, as SSH decreased, did not compensate for reductions in bite mass, and intake rate declined linearly (P=0.006) from 24.6 to 18.9 g OM min⁻¹. Lactating and dry cows compensated for the reduction in intake rate, by increasing total grazing time and total number of bites per day. As SSH decreased from 9 to 5 cm, lactating and dry cows increased total eating time (528 to 607 and 419 to 510 min), total GJM (40 400 to 49 300 and 31 300 to 40 600 GJM) and total bites (31 100 to 37 900 and 24 600 to 31 200 bites, respectively). As a result, there was no significant effect of SSH on daily intake of OM, although lactating cows had greater intakes than dry cows; 12.9 vs. 9.3 kg day⁻¹, (P<0.001). The increased time spent grazing as SSH decreased was associated with a reduction in the time spent ruminating (P<0.001), despite similar levels of daily intake being achieved across SSH treatments. Although dry cows had much lower daily intakes, they spent only about 30 min less each day ruminating than the lactating cows (P=0.060), allowing them 120 to 160 min more idling (i.e., non-grazing, non-ruminating) behaviour (P=0.001).     

The intake and digestion of a range of temperate forages by sheep and fibre-producing goats

The voluntary intake, digestibility and mean retention time of six temperate forages differing in their chemical composition by 12 adult castrated male Scottish blackface sheep, aged 15 months, and fibre-producing castrated male goats, aged 27 months, and of similar live weight, 40 kg, were described. The creation of a range of chemical compositions was effected through the use of barley straw, and a low- and high-digestibility hay, and the use of ammonia treatment of these forages. A wide range of voluntary intakes (42–78 g DM/kg W^0.75/day), digestibility of dry matter (0.46–0.60) and mean retention times of undigested residues (36–72 h) was achieved through feeding the six forages. Across all the forages fibre-producing goats had higher voluntary intakes, expressed on a metabolic live weight basis, and lower digestibility values than sheep, whereas the mean retention time of the undigested residues was similar for the two species. Within forages goats selected a diet of potentially higher nutritive value, as predicted from chemical composition, with a smaller particle size than sheep. It was concluded that the differences in intake and digestion of temperate forages between sheep and fibre-producing goats are broadly similar to those observed in other experiments between sheep and goats ingesting tropical forages.     

Cattle and sheep develop preference for drinking water containing grape seed tannin

Ingestion of small amounts of some types of condensed tannins (CTs) by ruminant livestock can provide nutritional, environmental and economic benefits. However, practical methods are needed to make these tannins more available to ruminant livestock. Results from previous trials with crude quebracho and black wattle tannin indicated that cattle and/or sheep would not preferentially drink water containing these tannins. Therefore, we conducted preference trials to determine if cattle and sheep would learn to prefer water containing purified grape seed tannin (GST) that provided up to 2% of their daily dry matter (DM) intake. After gradual exposure to increasing amounts of this tannin in water during a pre-trial period, five adult ewes and five yearling heifers fed lucerne (Medicago sativa) pellets (19% CP) were offered water and several concentrations of GST solutions for either 15 (sheep trial) or 20 days (cattle trial). We measured intake of all liquids daily. Concentrations of blood urea were also measured for heifers when they drank only tannin solutions or water. Both sheep and cattle developed preferences for water with GST in it over water alone (P < 0.01) although this preference appeared earlier in the trial for sheep than for cattle. For the sheep, mean daily intake of water alone and all tannin solutions (in total) was 0.6 and 6.1 l, respectively. For the cattle, mean daily intake of water and all tannin solutions in total was 21.8 and 20.6 l, respectively, in the first half of the trial and 10.8 and 26.1 l, respectively, in the second half of the trial. Compared with the other tannin solutions, both sheep and cattle drank more of the solution with the highest tannin concentration (2% of daily DM intake as GST) than of water on more trial days (P < 0.05). Ingestion of water with the highest concentration of GST reduced blood plasma urea concentration in the cattle by 9% to 14% (P ⩽ 0.10) compared with ingestion of water alone. Results from the trials suggest that providing grape seed and perhaps other CTs via drinking water may be a practical way to introduce CTs into sheep and cattle diets.     

Effects of water deprivation on urea metabolism in camels, desert sheep and desert goats fed dry desert grass

1. The effects of water restriction and complete water deprivation on nitrogen retention and urea recycling were examined in camels, desert sheep and desert goats fed only dry desert grass of 3.2% crude protein content. 2. All three species were in negative nitrogen balance when water was available ad libitum. 3. In camels urea recycling was consistently high (94-97%) and nitrogen balance did not change with treatment. 4. In sheep and goats urea recycling increased from 75% to 94% (sheep) and from 79% to 95% (goats) during water deprivation, and nitrogen balance improved to positive values. 5. In all species water deprivation depressed dry matter intake and increased apparent digestibility of dry matter and nitrogen. 6. The effects of water restriction were generally intermediate. 7. These results suggest that nitrogen metabolism in adult domestic livestock raised by nomadic pastoralists in Sudan is not harmed, and may in fact be improved by short periods of water deprivation.     

Impact of drinking of saline water on hemato-biochemical parameters of Black Bengal goats in the selected areas of Bangladesh

Global climatic changes are contaminating ground and surface water sources around the world, resulting in increased salinity. Knowing the animals' typical physiological capability for salinity tolerance without compromising their health is a necessity. The research was undertaken to determine the impacts of drinking water salinity on hemato-biochemical parameters of Black Bengal goats. A total of 40 Black Bengal goats (20 male and 20 female), age ranging from 1 to 5 years, were randomly selected and divided into 2 groups. The animals of group 1 received higher saline water (12 ppt) and those in group 2 received lower saline water (1 ppt) as regular drinking water. Blood parameters of all selected goats were measured. Serum creatinine, uric acid, urea, potassium, sodium, and chloride were significantly higher (P< 0.05) in the animals of group 1 compared with group 2, although serum phosphorous was significantly lower (P < 0.05) in group 1 compared with group 2. There were no significant differences in serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), glucose, magnesium, and calcium between the animals of group 1 and 2. AST and magnesium differed significantly (P < 0.05) between young and adult goats in group 1. Glucose and urea levels were slightly higher (P < 0.05) in young goats. In both groups, male goats had significantly higher (P < 0.05) serum potassium and urea levels than female goats. The results suggest that Black Bengal goats of the coastal areas have different salt tolerance capacities based on their age and sex, and adapt to higher salinity by changing kidney functions.     

Selective Brain Cooling Reduces Water Turnover in Dehydrated Sheep

In artiodactyls, arterial blood destined for the brain can be cooled through counter-current heat exchange within the cavernous sinus via a process called selective brain cooling. We test the hypothesis that selective brain cooling, which results in lowered hypothalamic temperature, contributes to water conservation in sheep. Nine Dorper sheep, instrumented to provide measurements of carotid blood and brain temperature, were dosed with deuterium oxide (D₂O), exposed to heat for 8 days (40◦C for 6-h per day) and deprived of water for the last five days (days 3 to 8). Plasma osmolality increased and the body water fraction decreased over the five days of water deprivation, with the sheep losing 16.7% of their body mass. Following water deprivation, both the mean 24h carotid blood temperature and the mean 24h brain temperature increased, but carotid blood temperature increased more than did brain temperature resulting in increased selective brain cooling. There was considerable inter-individual variation in the degree to which individual sheep used selective brain cooling. In general, sheep spent more time using selective brain cooling, and it was of greater magnitude, when dehydrated compared to when they were euhydrated. We found a significant positive correlation between selective brain cooling magnitude and osmolality (an index of hydration state). Both the magnitude of selective brain cooling and the proportion of time that sheep spent selective brain cooling were negatively correlated with water turnover. Sheep that used selective brain cooling more frequently, and with greater magnitude, lost less water than did conspecifics using selective brain cooling less efficiently. Our results show that a 50kg sheep can save 2.6L of water per day (~60% of daily water intake) when it employs selective brain cooling for 50% of the day during heat exposure. We conclude that selective brain cooling has a water conservation function in artiodactyls.     

Influence of the subfornical organ on meal-associated drinking in rats

A lesion of the subfornical organ (SFO) may disrupt drinking after a meal of dry chow as it does drinking after intragastric administration of hypertonic saline. Food and water intakes of SFO-lesioned (SFOX) and sham-lesioned rats were measured during 90-min tests following various lengths of food deprivation. During the tests, all rats began eating before they began drinking. After 20-24 h of food deprivation, latency to begin drinking after eating had started was longer for SFOX than for sham-lesioned rats. Plasma osmolality was elevated by 2-3% in both lesion groups at 12 min, the latency for sham-lesioned rats to drink, but SFOX rats nevertheless continued eating and delayed drinking. Eating after shorter 4-h food deprivations and ad libitum feeding produced more variable drinking latencies and less consistent effects of SFO lesion. During 24 h of water deprivation, SFO lesion had no effect on the suppression of food intake and did not affect food or water intakes during the first 2 h of subsequent rehydration. These findings indicate that the SFO is involved in initiating water intake during eating and in determining drinking patterns and the amount of water ingested during a meal.     

Ingestive Pattern Changes in Blinded Rats

Eating and drinking patterns were examined in intact and blinded adult male Sprague-Dawley rats fed a choice among isocaloric casein, sucrose/dextrin, and vegetable shortening/soybean oil diets. Weekly mean intake of all nutrients was altered in blinded rats, with increased lipid intake and decreased water intake in rats blinded for 2 weeks, lower carbohydrate but higher protein and water intakes in rats blinded for 4 weeks, while 2 weeks later blinded rats maintained high intakes of protein and water. The amplitudes of the daily rhythms for each nutrient behaved similarly to the weekly intakes. Delayed daily time of peak intake for all nutrients over successive weeks after blindness were found, indicating that the timing of peak intake free-runs. 24 h profile indicated time of day variations of nutrient intake tending to be less marked over successive weeks of blindness. Free-running animals maintained the link between carbohydrate intake and hypothalamus serotonin.     

Effect of water trough type on the drinking behaviour of pasture-based beef heifers

The objective of this study was to investigate the effects of different trough types on the water consumption and drinking behaviour of pasture-based beef heifers. Two trials were implemented with 32 beef heifers to test two different types of water troughs, namely a rectangular concrete trough (RC) and a round polyvinyl chloride water tank (PVC). In Trial 1, both troughs were simultaneously available to groups of four animals within eight paddocks. In Trial 2, the animals were distributed in pairs throughout 16 paddocks and, in a crossover design, were exposed to one type of trough at a time. In both trials, estimated water intake was per four animals. Number of drinking bouts, time spent drinking and amount of water intake from the RC and PVC trough were recorded in both trials. Data were statistically analysed by analysis of variance. In Trial 1, group and trough effect were in the model. In Trial 2, stage, pair and trough were tested. In Trial 1, where both types of troughs were available, animals had a higher number of drinking bouts (3.32 v. 0.57 ± 0.09; P < 0.01), longer drinking periods (144.21 v. 22.81 ± 7.3 s; P < 0.01) and greater intake (160.21 v. 23.76 ± 13.06 l; P < 0.01) from the PVC water tank, compared to the RC trough. In Trial 2, all groups drank more often (5.10 v. 3.28 ± 0.32; P < 0.001), for longer periods (167.23 v. 115.23 ± 15.61 s; P < 0.02) and with higher intake (141.36 v. 118.47 ± 5.01 l; P < 0.02) from the PVC than from the RC trough. Thus, heifers not only prefer, but also drink more from a PVC water tank in comparison to a RC trough.     

The estimation of food intake, and its seasonal variation, in the Hartebeest

This paper describes a method of estimating the food intake of a grazing species, Coke's hartebeest, using material from thirty-two freshly killed animals, taken in different seasons. The literature suggests that the retention time of particles in the cow's rumen is dependent on their specific gravity. The proportions of the leaf, sheath and stem of grasses in the hartebeest's rumen were assessed and their specific gravities measured. Their characteristic retention times, used in conjunction with the weight of rumen contents, allowed calculation of the daily intake of each hartebeest. The use of specific gravity is justified by the relationships between the specific gravity and proximate composition of the grass samples. The intakes showed a three fold range, with the lowest mean value of 26.1 ±4.7 g/kg.W*⁷³. day in the dry season. A reduced intake of low quality feeds is consistent with published theories on the factors regulating the intakes of roughages by ruminants. The hartebeest's changing intake is paralleled by other changes in its digestive tract, notably the concentrations of nitrogen in the rumen and faeces. A regression predicting the hartebeest's intake from the faecal nitrogen concentration is developed. Intake is shown to depend upon the water content of the diet, through its effect on specific gravity and hence retention time. The water content is determined by the effective rainfall over the previous 3 months. The limitations of the method, particularly in the measurement of specific gravity, are discussed. A number of reported intakes by cattle and sheep, with the result of a feeding trial with one hartebeest, are presented to show that the estimated intakes may be close to their actual values.     

Behaviour of goats,sheep and cattle and their selection of browse species on natural pasture in a Sahelian area

A study was conducted in the Sahelian zone of Burkina Faso of the behaviour of cattle, sheep and goats on natural pasture and their preference for browse species. Concurrently, a survey was undertaken on a sample of farmers (herders, women and livestock owners) in the study area to estimate the indigenous knowledge of browse species and their utilisation by ruminants. A herd of cattle and flocks of sheep and goats belonging to farmers were followed on pasture, each species during three consecutive days each month, from May 2003 to April 2004, and their activities were recorded regularly every 15 min, as well as the browse species selected and the height reached while browsing. The farmers had good knowledge of the browse species present in the area and their preferential classification depended on the availability of the species, their nutritive value and also other ways of utilising the species concerned. However, some divergence existed in the knowledge of farmers compared to the result from the behaviour study, e.g. some species were mentioned by farmers but not found in the inventory. There was a decline in the feeding activities of all animal species from rainy to dry season, while resting and ruminating activities were increasing at the same time. This decline in time spent feeding was more important for cattle (from 72 to 39% of total time) as they relied on the herbaceous biomass for feeding, while sheep and goats made a shift in the feeding activities from grazing to browsing when the herbaceous biomass decreased. Cattle browsed (leaves and litter) during all the study period for around 4.5% of the time spent on pasture. Sheep and goats showed a peak in browsing activity in the dry season, 28 and 52% of the time, respectively. During the whole observation period, cattle browsed 10 species, with Guiera senegalensis most often selected, with 59, 54 and 84% of browsing time, respectively, in the rainy, post rainy and dry season. G. senegalensis, Combretum micranthum and Balanites aegyptiaca were the most important species browsed by sheep among the 20 browse species selected. Goats browsed more than 20 species daily but the most preferred species were Acacia senegal, B. aegyptiaca and Pterocarpus lucens. The mean height reached by goats when browsing was higher (1.65 m) than that of cattle (1.47 m) and sheep (0.87 m). The result from this study can be used to select species for regeneration and to advice farmers on the importance of herd composition.     

Fruit consumption in migratory passerines is limited by water ingestion rather than by body water balance

Many insectivorous passerines become frugivorous during migration. Because water may facilitate the digestion of dry fruits, some passerines may benefit from staging in stopover sites that offer access to drinking water. In autumn, water consumption by blackcaps Sylvia atricapilla staging in Israel was found to induce a shift from insectivory to frugivory. We tested two alternative hypotheses concerning the mechanism facilitating consumption of the relatively dry fruits which are common in this region: 1) water intake facilitates the passage of fruits within the digestive tract when these two resources are simultaneously ingested, and 2) improved body water balance allows the consumption and ingestion of large amounts of dry fruits. Blackcaps were subjected to five treatments that included temporal separation of water and fruit consumption, as well as subcutaneous water injection to maintain balanced body water in water‐deprived birds. Fruit consumption rate was measured daily. We found that only simultaneous provisioning of water and fruits significantly increased fruit consumption rate, implying that drinking water directly improves fruit digestion within the digestive system. Furthermore, the fuel deposition rate increased with increased fruit consumption rate. These results emphasize the importance of water availability for the ecology and conservation of migrating passerines.     

The intake and digestion of maize silage-based diets by dairy cows and sheep

Six lactating cows, 6 dry cows and 6 wether sheep were fed ad libitum on diets of maize silage, maize silage plus lucerne, or maize silage plus lucerne plus wheat. Faeces and urine collections allowed for the determination of digestibility of dry matter, organic matter and nitrogen, and balances of nitrogen and water.

Voluntary feed intakes were highest and digestibility values were lowest in lactating cows. The addition of lucerne reduced organic matter digestibility in dry cows, but not in lactating cows or sheep. The addition of wheat decreased intake in dry cows and sheep, but not in lactating cows. Production of milk, protein, solids-not-fat and total solids increased with dietary quality, but there was a depression in milk fat content as a result of wheat supplementation.

The ranking of the 3 diets on the basis of feed intake differed with each class of livestock, but lactating cows and sheep gave the same ranking on the basis of organic matter digestibility.     

Drinking water is associated with weight loss in overweight dieting women independent of diet and activity

Background: Data from short‐term experiments suggest that drinking water may promote weight loss by lowering total energy intake and/or altering metabolism. The long‐term effects of drinking water on change in body weight and composition are unknown, however. Objective: This study tested for associations between absolute and relative increases in drinking water and weight loss over 12 months. Methods and Procedures: Secondary analyses were conducted on data from the Stanford A TO Z weight loss intervention on 173 premenopausal overweight women (aged 25–50 years) who reported <1 l/day drinking water at baseline. Diet, physical activity, body weight, percent body fat (dual‐energy X‐ray absorptiometry), and waist circumference were assessed at baseline, 2, 6, and 12 months. At each time point, mean daily intakes of drinking water, noncaloric, unsweetened caloric (e.g., 100% fruit juice, milk) and sweetened caloric beverages, and food energy and nutrients were estimated using three unannounced 24‐h diet recalls. Beverage intake was expressed in absolute (g) and relative terms (% of beverages). Mixed models were used to test for effects of absolute and relative increases in drinking water on changes in weight and body composition, controlling for baseline status, diet group, and changes in other beverage intake, the amount and composition of foods consumed and physical activity. Results: Absolute and relative increases in drinking water were associated with significant loss of body weight and fat over time, independent of covariates. Discussion: The results suggest that drinking water may promote weight loss in overweight dieting women.     

Feeding behavior, rumination, reticulo-ruminal fermentation and plasma volatile fatty acids, compared in goats and sheep; influence of the diet

Two-year old Alpine she-goats (n = 3) and Texel ewes (n = 3) were compared as to eating behaviour, rumination and volatile fatty acids (VFA) in rumen and blood. The animals were fed once daily with two different proportions (20 and 80%) of barley and hay. Dry matter intake was fixed at 48 g D.M/kg P0.75 per day. In similar feeding and environmental conditions, eating behaviour and rumination of goats and sheep did not differ much: the goats tended to eat faster and there were more rumination periods in the sheep. Latency time, mean duration of rumination periods, daily rumination time and circadian pattern of rumination did not differ significantly between the two species (fig. 1). With both diets we observed a higher VFA concentration and a lower acetate/propionate ratio in the rumen of the ewes; however, rumen pH was lower only in those eating the 80% barley ration (fig. 2). Blood VFA in the jugular vein did not differ between sheep and goats (fig. 3). The proportion of cereals and hay in the diets affected rumen fermentation and rumination pattern in both species. With a higher concentrate/roughage ratio, rumen and plasma VFA increased, while the pH and acetate/propionate ratio in the lumen juice, the number of rumination periods and daily rumination time decreased. When the animals were fed the 80% barley ration, there was practically no rumination in the first 9 h after the single meal. During this time, rumen pH was minimal and VFA levels in the rumen and blood were maximal.     

Validation of a system for monitoring individual feeding and drinking behaviour and intake in young cattle

The objective of this study was to validate an electronic system for monitoring individual feeding and drinking behaviour and intake developed for young cattle housed in group. A total of 35 Holstein–Gyr crossbred heifers (BW: 180±52 kg; age: 121.5±32.5 days), fitted with an ear tag containing a unique passive transponder, were distributed in three groups of 12, 12 and 11 animals per period and had free access to 12 electronic feed bins and two electronic water bins (Intergado® Ltd). The dimensions of feed and water bins, as well as the sensors position were appropriate for young cattle. The system documented the visit frequency and duration, as well as the feed and water intakes, by recording the animal’s identification tag, bin number, initial and final times of visits and the difference of feed/water weight at the start and end of each bin visit. Feed bins were monitored using time-lapse video recording over 4 days and the water bins were monitored over 6 days. For each feed bin, two feeding events were monitored using manual weighings with an external scale immediately before and after the animal’s visit and the difference between them was assumed as feed intake (n=24 observations). For the water bins, 60 manual weighings were made. Video and manual weighing data were regressed on the electronic feeding and drinking behaviour and intake data to evaluate the system’s precision and accuracy. The system showed high specificity (98.98% and 98.56% for the feed and water bins, respectively) and sensitivity (99.25% and 98.74%, respectively) for identifying an animal’s presence or absence. Duration of feed and water bin visits as well as feed and water consumption per visit estimated by the system were highly correlated and precise compared with the observed video and manual weighing data (r²=0.917, 0.963, 0.973 and 0.986, respectively). It was concluded that Intergado® system is a useful tool for monitoring feeding and drinking behaviour as well as water and feed intakes in young cattle housed in groups.