Effects of intermittent watering on water balance and feed intake in male Ethiopian Somali goats

Morphophysiological Responses of the Goat Mammary Gland to Water Scarcity in Arid and Semi-Arid Environments: Are They Enough to Generate Adaptation to New Climatic Challenges?

Due to climate change, diverse territories of the planet will suffer from water restrictions. Goats are perceived as the most resilient ruminants in this scenario. So, various studies have focused on describing how a lower water intake influences milk production, especially in breeds adapted to desert environments. In water-stress situations, goats lose up to 32% of their body weight (BW), the rate of passage is reduced, and the digestibility of the feed increases. When goats consume water again, the rumen prevents hemolysis and osmotic shock from occurring. Regarding milk production, the response varies depending on the breed and the level of water restriction, maintaining the milk volume or reducing it by up to 41%. Systemically, it decreases the urinary volume and glomerular filtration rate, increasing blood osmolality and the vasopressin (ADH) concentration. Studies are scarce regarding changes in blood flow to the mammary gland, but there would be a reduction in blood flow velocity of up to 40% without changing blood pressure. New studies must be undertaken to determine which breeds or crosses are the best adapted to changing environmental conditions and to improve our understanding of the changes that occur at the morphophysiological level of the caprine mammary gland.

Effects of Restricted Availability of Drinking Water on Blood Characteristics and Constituents in Dorper, Katahdin, and St. Croix Sheep from Different Regions of the USA

Different hair sheep breeds originated from diverse climatic regions of the USA may show varying adaptability to water deprivation. Therefore, the objective of this study was to assess the effects of restricted availability of drinking water on blood characteristics and constituent concentrations in different breeds of hair sheep from various regions the USA. For this study, 45 Dorper (initial age = 3.7 ± 0.34 yr), 45 Katahdin (3.9 ± 0.36 yr), and 44 St. Croix (2.7 ± 0.29 yr) sheep from 45 farms in 4 regions of the USA (Midwest, Northwest, Southeast, and central Texas) were used. Ad libitum water intake was determined during wk 2 of period one, with 75% of ad libitum water intake offered during wk 2 of period two, and 50% of ad libitum water intake offered for 5 wk (i.e., wk 5−9) in period three. Water was offered at 07:00 or 07:30 h, with blood samples collected at 08:00 and(or) 14:00 h in wk 1, 2, 3, 4, 8, and 9 for variables such as hemoglobin and oxygen saturation and wk 2, 4, 6, 8, and 9 for concentrations of glucose and other constituents. The blood oxygen concentration at 08:00 h was 4.86, 4.93, and 5.25 mmol/L in period one and 4.89, 4.81, and 5.74 mmol/L in period three for Dorper, Katahdin, and St. Croix, respectively (SEM = 0.160; p = 0.001). Blood oxygen at 14:00 h was 4.37, 4.61, and 4.74 mmol/L in period one and 4.66, 4.81, and 5.46 mmol/L in period three for Dorper, Katahdin, and St. Croix, respectively (SEM = 0.154; p = 0.003). St. Croix were able to maintain a higher (p < 0.001) blood oxygen concentration than Dorper and Katahdin regardless of water availability. The pattern of change in blood concentrations with advancing time varied considerably among constituents. However, concentrations of glucose (55.3 and 56.2 mg/dL; SEM = 0.84), lactate (24.1 and 22.5 mg/dL; SEM = 0.79), total protein (7.08 and 7.17 g/dL; SEM = 0.0781), and albumin (2.59 and 2.65 g/dL in wk 2 and 9, respectively; SEM = 0.029) were similar (p > 0.05) between periods one and three. Conversely, concentrations of cholesterol (56.2 and 69.3 mg/dL; SEM = 1.33) and triglycerides (28.6 and 34.5 mg/dL in wk 2 and 9, respectively; SEM = 0.98) were greater (p < 0.05) in period three vs. 1. In conclusion, water restriction altered almost all the blood variables depending upon severity and duration of restriction, but the hair sheep breeds used from different regions of the USA, especially St. Croix, displayed considerable capacity to adapt to limited drinking water availability.

Feed digestibility, digesta passage and faecal microbial biomass in desert-adapted goats exposed to mild water restriction

In arid and semi-arid environments, extensively managed ruminants regularly experience drinking water shortage, especially in the dry season. The present study therefore investigated the effects of mild drinking water restriction on feed intake, feed digestibility, solid digesta passage and composition of faeces including faecal microbial biomass. A feeding trial was conducted in Oman, during the dry summer months. Nine adult male Batinah goats were subjected to three watering regimes in a 3 × 3 Latin Square design. Treatments were (1) water offered ad libitum (100%, W100); (2) water restricted to 85% ad libitum consumption (W85); and (3) water restricted to 70% ad libitum consumption (W70). Animals were offered Rhodes grass hay and whole barley grains (1:1 ratio) at 1.3 times maintenance energy requirements. Each of the three experimental periods comprised 16 days of adaptation and 8 days of measurements. During the latter, feed offered and refused as well as faeces were sampled and quantified. Gastrointestinal digesta passage was determined using ytterbium-labelled Rhodes grass hay. Ergosterol and amino sugars were used as markers for faecal microbial biomass, that is the sum of fungi and bacteria. Water restriction had no effect on feed intake and digesta passage. However, feed dry matter, organic matter and fibre digestibility increased (p < 0.05) in W70 compared with W85, and the excreted amount of faecal dry matter, organic matter, nitrogen and neutral detergent fibre decreased (p < 0.05) in W70 compared with W85. Even though water restriction did not affect total faecal microbial biomass carbon (C) concentration, that of fungal biomass C increased (p < 0.05) in W70 compared with W85. Therefore, mild water restriction seems unproblematic from a physiological and nutrient utilization perspective as it increases feed digestibility without compromising feed intake.

Effect of Different Watering Regimes in Summer Season on Water Intake, Feed Intake, and Milk Production of Marecha She-camel (Camelus dromedarius)

Simple Summary

Camel livestock is a significant sector of agriculture in Pakistan. Punjab Marecha is the camel breed more diffuse for their production characteristics. In fact, this camel breed is well adapted to the desert ecosystem, tolerating elevated temperatures and dehydration. This study aimed to evaluate the effect of water deprivation on milk production performance in Marecha camels during the summer. Twelve she-camels in the early lactation stage were included. After seven days, camels were divided into three groups: Group 1 (G1) having access to water once a day, Group 2 (G2) having access once every 4 days, and Group 3 (G3) having access once every 6 days. Milk production and daily dry matter were decreased in camels deprived of water for 6 days. The results of the current study suggest that the camel is a productive animal even when subjected to water deprivation; however, its feed intake and milk production are decreased.

Abstract

Twelve lactating healthy Marecha she-camels in the early lactation stage during the summer at Camel Breeding and Research Station Rakh-Mahni (Pakistan) were included. All animals were fed with Medicago sativa and Cicer arientinum ad libitum and divided into three groups in relation to the access to water, after a period of seven days of adaptation to experimental conditions. Group 1 (G1) was considered as control having access to water once every day; Group 2 (G2) had access once every 4 days, while Group 3 (G3) had access once every 6 days. The duration of the study was 60 days with an adaptation period to experimental conditions of 7 days before the onset of the study. Dry matter intake (DMI) was calculated on a dry matter basis. On average the ambient temperature and relative humidity during the trial were 39–41 °C and 55–63%, respectively. The DMI, water intake, milk production, and body weight changes were affected (p < 0.001) during various watering regimes. The mean values of water intake were found to be 82.94 ± 1.34 L higher in G3 than G1 and G2.

Effects of restricted availability of drinking water on body weight and feed intake by Dorper, Katahdin, and St. Croix sheep from different regions of the USA

Resilience to restricted availability of drinking water was evaluated with 44 Dorper (DOR; initial age = 3.7 ± 0.34 yr), 42 Katahdin (KAT; 3.9 ± 0.36 yr), and 42 St. Croix (STC; 2.7 ± 0.29 yr) sheep from 46 farms in 4 regions of the USA (Midwest, MW; Northwest, NW; Southeast, SE; central Texas, TX). Ad libitum water intake was determined during 2 wk of period 1, with 75% of this amount offered in 2 wk of period 2 and 50% in 5 wk (i.e., 5 to 9) of period 3. Body weight and DMI in week 2 of period 1 and week 9 of period 3 were analyzed with a mixed effects model. There was a breed × period interaction (P = 0.023) in water intake relative to BW (6.17, 6.69, and 7.19 in period 1 and 3.04%, 3.26%, and 3.36% BW in period 3 for DOR, KAT, and STC, respectively; SEM = 0.219). There were 3-way interactions of breed, region, and period in BW and DMI in g/d (P < 0.010). For STC, BW was greater (P < 0.05) in period 3 vs. 1 for all regions (50.1, 47.6, 42.4, and 45.8 kg in period 1 and 51.9, 49.3, 44.5, and 47.7 kg in period 3), whereas there was only a period difference for DOR from the MW and SE (61.4, 66.0, 64.6, and 59.6 kg in period 1 and 60.6, 66.5, 65.7, and 62.4 kg) and for KAT from TX (50.1, 47.6, 42.4, and 45.8 kg in period 1 and 51.9, 49.3, 44.5, and 47.7 kg in period 3 for MW, NW, SE, and TX, respectively; SEM = 2.57). In accordance, DMI by STC was similar (P > 0.05) between periods for all regions (1.25, 1.17, 1.06, and 1.16 kg/d in period 1 and 1.12, 1.08, 1.02, and 1.02 kg/d in period 3), as was also the case for DOR from MW and SE but not from NW or TX (1.54, 1.50, 1.30, and 1.41 kg/d in period 1 and 1.41, 1.13, 1.25, and 1.18 kg/d in period 3) and KAT from TX though not from the other 3 regions (1.47, 1.52, 1.48, and 1.40 kg/d in period 1 and 1.06, 1.15, 1.30, and 1.33 kg/d in period 3 for MW, NW, SE, and TX, respectively; SEM = 0.061). In conclusion, based on BW and DMI with water intake restricted at 50% of ad libitum consumption by individual animals, STC appeared more consistent in display of high resilience to restricted water availability, although DOR from 2 regions and KAT from 1 also were relatively resilient. The results suggest benefit to breed comparisons of inclusion of animals from multiple areas and that environmental conditions of regions may have disparate effects with different breeds of hair sheep.

Small Ruminants: Farmers' Hope in a World Threatened by Water Scarcity

Simple Summary

Water is one of the most important nutrients to livestock. It is so essential that more than half the volume of the animal's body is water. However, its availability is threatened by the irreversible changes in climate, which has culminated into reduced rainfall in most regions of the world. Such an increasing threat to regular water supply, and by extension to food security and livelihood has forced a shift from large to small ruminant production, especially in regions experiencing low rainfall, with farmers taking advantage of their adaptive process and efficiency of water use. Small ruminants, especially desert goats, can adaptively survive in water-limited areas while trekking long distance in search of feed and they will regain any weight loss at the next watering point. Further research is needed on adaptive indigenous breeds of small ruminants since tolerance to water scarcity is breed dependent, so that improvements can be made through effective selection and breeding program.

Abstract

The availability and sustainability of suitable and good quality drinking water is a global concern. Such uncertainties threaten livestock production with an attendant ripple effect on food security. Small ruminants, including sheep and goats, appear to be promising to smallholder farmers in solving this problem because of their ability to survive in water-limited areas and harsh environment when compared with large ruminants. Their small body size is also seen as an advantage, because less water will be required for proper digestion and feed utilization. Therefore, this review will provide information regarding the adaptive responses of small ruminants on thermoregulation, blood metabolites, immune status, drug pharmacokinetics, reproduction and hormonal indices during the period of water stress. Adaptable and indigenous breeds are known to be more tolerant to water stress than selected breeds. A drop in feed intake and weight reduced respiratory rate and increased concentration of blood metabolites are the general effects and/or observations that are encountered by small ruminants during the period of water stress. The concept of water tolerance either as deprivation and/or restriction of indigenous and adaptable breeds of small ruminants is gaining ground in research studies around the world. However, more research, however, seeking to explore water tolerance capacity of adaptable breeds especially in arid and water limiting areas are still needed.

Effects of level of brackish water on feed intake, digestion, heat energy, and blood constituents of growing Boer and Spanish goat wethers

Twenty Boer (6.1 mo old and 21.3 kg) and 20 Spanish (6.6 mo old and 19.7 kg) goat wethers were used to determine effects of brackish water on feed intake, digestion, heat energy, and blood constituents. Brackish water had 6,900 mg/L total dissolved salts, 1,885 mg/L Na, 75 mg/L Mg, 1,854 mg/L chloride, 2,478 mg/L sulfate, and 9 mg/L boron. Water treatments were 100% tap water (control), 100% of a brackish water source (100-BR), 33% control and 67% brackish water (67-BR), and 67% control and 33% brackish water (33-BR). Water and a moderate-quality grass hay (8.5% CP and 68% NDF) were offered free choice. The experiment consisted of 14 d of adaptation, 5 d for metabolizability measures, and 2 d for determining gas exchange and heat energy. There were no interactions ( > 0.05) between breed and water treatment. Water intake (931, 942, 949, and 886 g/d [SE 59.1] for the control, 33-BR, 67-BR, and 100-BR, respectively) and DM intake (525, 556, 571, and 527 g/d [SE 31.0] for the control, 33-BR, 67-BR, and 100-BR, respectively) were similar among treatments ( = 0.876 and = 0.667, respectively). Urinary water was greater for brackish water treatments than for the control ( = 0.003; 211, 317, 319, and 285 g/d [SE 25.6] for the control, 33-BR, 67-BR, and 100-BR, respectively) and fecal water content was similar among treatments ( = 0.530; 247, 251, 276, and 257 g/d [SE 19.0] for the control, 33-BR, 67-BR, and 100-BR, respectively), implying less water loss by other means such as evaporation when brackish water was consumed. Total tract OM digestibility was lower ( = 0.049) for treatments with brackish water than for treatments without brackish water (64.2, 61.5, 58.6, and 59.3% [SE 1.86] for the control, 33-BR, 67-BR, and 100-BR, respectively), although ME intake was similar among treatments ( = 0.940; 4.61, 4.57, 4.60, and 4.31 MJ/d [SE 0.394] for the control, 33-BR, 67-BR, and 100-BR, respectively). Daily heat energy in kilojoules per kilogram BW was less with brackish water than without brackish water ( = 0.001; 474, 436, 446, and 445 kJ/kg BW [SE 7.7] for the control, 33-BR, 67-BR, and 100-BR, respectively), although values in megajoules were similar among treatments ( = 0.588; 4.36, 4.12, 4.22, and 4.18 MJ [SE 0.124] for the control, 33-BR, 67-BR, and 100-BR, respectively). Body weight of wethers consuming brackish water decreased less than that of wethers consuming the control water ( = 0.006; -37, -14, -7, and -16 g [SE 7.2] for the control, 33-BR, 67-BR, and 100-BR, respectively), but recovered energy was similar among treatments ( = 0.923; 0.25, 0.45, 0.38, and 0.13 MJ/d [SE 0.356] for the control, 33-BR, 67-BR, and 100-BR, respectively). In conclusion, brackish water inclusion in drinking water had a number of effects, but it does not appear that consumption of this source would adversely impact performance of growing meat goats.

Effect of increased dietary salinity on the reproductive status and energy intake of xeric and mesic populations of the spiny mouse, Acomys

The possible role of increased dietary salinity as a proximate regulator of reproduction in xeric population of golden spiny mice (Acomys russatus) and mesic population of common spiny mice (A. cahirinus) was tested. In the wild, as the dry season progresses, evaporative water loss in the vegetation increases. This leads to increase in particle concentration of plant tissues. Thus, species consuming a plant diet are exposed to increased dietary salinity. Both male and female individuals of A. russatus were subjected to gradually increasing dietary salinity (0.9%, 2.5%, 3.5%, and 5%) while those of A. cahirinus only up to 3.5% for a total period of 8 and 6 weeks, respectively. Urine osmolarity showed a significant increase under 3.5% and 5% salinity in A. russatus and 2.5% and 3.5% in A. cahirinus. Testis mass and spermatogenesis were significantly reduced while uterine mass and vaginal estrus cycles were not affected in A. russatus. None of the parameters was significantly affected in A. cahirinus. Increase in salinity also significantly reduced body mass in A. russatus but not in A. cahirinus. Mass-specific daily digestible energy intake was not significantly affected by increased salinity in both species. Recovery individuals regained body mass quickly and surpassed initial values after four weeks. However, testis mass and spermatogenesis did not show recovery. The results suggest that increase in dietary salinity could be used as a proximate signal to regulate reproduction in A. russatus by halting it in males, as the dry season progresses while such role in the mesic population of A. cahirinus is unlikely.