Supplementation Of Drinking Water Research Articles

Effects of water supplementation with tryptophan and vitamin B6 or feeding hydrogenated fat on reducing hunger-induced drinking pre-slaughter in pigs

Faucitano, L., Torrey, S., Matte, J. J., del Castillo, J. R. E. and Bergeron, R. 2012. Effects of water supplementation with tryptophan and vitamin B6 or feeding hydrogenated fat on reducing hunger-induced drinking pre-slaughter in pigs. Can. J. Anim. Sci. 92: 319–326. A current food safety challenge at pig slaughter plants comes with the presence of stomachs filled with liquid induced by hunger-related drinking in lairage. With the objective to reduce hunger-related excess drinking, 30 barrows were assigned to three treatments (10 pigs per treatment): (1) unsupplemented water or feed regimen (CONT), (2) L-Tryptophan (3 g L−1) and vitamin B6 (10 mg L−1) in the drinking water for 5d (TRP-B6), (3) hydrogenated fat (HF) supplemented at 10% in the diet for the last day of feeding before pre-slaughter fasting. As compared with CONT, neither TRP-B6 nor HF supplementation influenced behaviour in lairage and water intake at anytime over the pre-slaughter fasting period as reflected on stomach weight and its liquid content at slaughter (P>0.10). However, in HF-fed pigs plasma non-esterified fatty acids concentrations tended to be lower (P=0.09) while carcass yield was higher (P=0.04) than CONT pigs. It appears, therefore, that neither drinking water supplementation with TRP-B6 for 5 d nor feeding HF the last day before slaughter can be recommended strategies to limit excess water drinking prior to slaughter and liquid stomach content at slaughter. However, dietary HF supplementation the last day before slaughter may attenuate the effects of fasting on body energy reserves and improve carcass yield.

Hepatic Reduction of Carbamoyl-PROXYL in Ferric Nitrilotriacetate Induced Iron Overloaded Mice: An <i>in Vivo</i> ESR Study

Reduction of a nitroxyl radical, carbamoyl-PROXYL in association of free radical production and hepatic glutathione (GSH) was investigated in iron overloaded mice using an in vivo L-band electron spin resonance (ESR) spectrometer. Significant increases in hepatic iron, lipid peroxidation and decrease in hepatic GSH were observed in mice intraperitoneally (i.p.) administrated with ferric nitrilotriacetate (Fe(III)-NTA, a total 45 µmol/mouse over a period of 3 weeks). Free radical production in iron overloaded mice was evidenced by significantly enhanced rate constant of ESR signal decay of carbamoyl-PROXYL, which was slightly reduced by treatment with iron chelator, deferoxamine. Moreover, the rate constant of ESR signal decay was negatively correlated with hepatic GSH level (r=-0.586, p<0.001). On the other hand, hepatic GSH-depletion (>80%) in mice through daily i.p. injection and drinking water supplementation of L-buthionine-[S,R]-sulfoximine (BSO) significantly retarded ESR signal decay, while there were no changes in serum aspartate aminotransferase and liver thiobarbituric acid-reactive substances levels. In conclusion, GSH plays two distinguish roles on ESR signal decay of carbamoyl-PROXYL, as an antioxidant and as a reducing agent, dependently on its concentration. Therefore, it should be taken into account in the interpretation of free radical production in each specific experimental setting.

Assessing the effect of administering different probiotics in drinking water supplement on broiler performance, blood biochemistry and immune response

A study was conducted to evaluate three different probiotics, using drinking water supplemented with protexin, biovet and yoghurt. The day old broiler chicks were randomly divided into 12 separate floor pens each comprising 25 birds and three pens (replicates) per treatment group following completely randomised design. At 28 and 39 days of age body weight (BW) and feed to gain ratio (FCR) were determined. At the end of experiment, nine birds per treatment were sacrificed to evaluate carcass characteristics, abdominal fat contents and the internal organs. Blood haemato-biochemical parameters were determined. Haemagglutination inhibition antibody titres against Newcastle disease virus and lymphoid organs weight/body weight ratio were also determined. The BW of birds given probiotics was significantly greater than control (without probiotics) at both 28 and 39 days of age. Similarly, better FCR was observed in birds those given drinking water with probiotics. There was less mortality recorded with probiotics treatments. Differences in carcass characteristics, organs weight, meat composition and haematological values among all the treatments were non-significant. However, abdominal fat contents reduced significantly in probiotics supplemented groups as compared to control and cholesterol contents were reduced significantly supplemented groups as compared to control at both 21 and 39 days of age. Feeding of probiotics did positively affect the immune system within the parameters measured. It may be concluded that performance, blood chemistry, immunity against disease and economic efficiency in broilers could be maintained when supplementing any probiotic incorporated in broiler's drinking water.

Determination of the Pharmacokinetics and Oral Bioavailability of Salicylamine, a Potent γ-Ketoaldehyde Scavenger, by LC/MS/MS.

Levels of reactive γ-ketoaldehydes derived from arachidonate increase in diseases associated with inflammation and oxidative injury. To assess the biological importance of these γ-ketoaldehydes, we previously identified salicylamine as an effective γ-ketoaldehyde scavenger in vitro and in cells. To determine if salicylamine could be administered in vivo, we developed an LC/MS/MS assay to measure salicylamine in plasma and tissues. In mice, half-life (t1/2) was 62 minutes. Drinking water supplementation (1-10 g/L) generated tissue concentrations (10-500 μM) within the range previously shown to inhibit γ-ketoaldehydes in cells. Therefore, oral administration of salicylamine can be used to assess the contribution of γ-ketoaldehydes in animal models of disease.

Effect of lycopene on semen quality, fertility and native immunity of broiler breeder

1. The effect of drinking water supplementation with lycopene on the semen quality, fertility and immunity of broiler breeders was evaluated. 2. Broiler breeder males were individually caged from 25 to 42 weeks old and divided into two group: L group, treated birds (lycopene 0.5 g/l) and C group, control birds. Laying hens were divided into two groups and artificially inseminated. 3. Semen variables were evaluated and daily fertility recorded. Serum bactericidal activity was tested. 4. Semen production and viability were affected by lycopene supplementation. Serum bactericidal activity was better in L than in C group. The fertility rate curve of the L group displayed a positive trend.

Resilience and vulnerability are dose-dependently related to neonatal stressors in mice

Early life experiences have been shown to adjust cognitive abilities, stress reactivity, fear responses and immune activity in adult mammals of many species. However, whereas severe stressors have been generally associated with the emergence of hypothalamic pituitary adreno-cortical (HPA)-mediated pathology, mild neonatal stressful experiences have been traditionally associated with ‘positive’ effects or resilience. External stressors stimulate the HPA axis to induce a corticosterone secretion in mouse dams, which, in turn is directly transmitted to the progeny through lactation. Such corticosteroid transfer may offer a unitary mechanism whereby early low corticosterone exposure may favor resilience in the offspring and high corticosterone increase vulnerability to pathology. In this study we further investigated this hypothesis by evaluating the long-term effects of a neonatal exposure to low (33 mg/l) and high (100 mg/l) doses of corticosterone during the first 10 days of life in outbred CD-1 mice through supplementation in the maternal drinking water. Offspring attentional set-shifting abilities, central neurotrophic regulation and levels of natural auto-antibodies (na-Abs) directed to serotonin (SERT) and dopamine (DAT) transporters were assessed in adulthood. While low levels of neonatal corticosterone improved adult cognitive abilities and increased na-Abs levels directed to SERT, high doses of neonatal corticosterone reduced hippocampal BDNF levels and na-Abs directed to DAT. These findings confirm and extend our previous findings, supporting the view that both adaptive plasticity and pathological outcomes in adulthood may depend on circulating neonatal corticosterone levels and that these effects follow a U-shaped profile.

Physiological stress responses in broilers as affected by drinking water supplements or dietary corn particle size

The detrimental effects of physiological stress on broilers are well documented. However, little research exists to delineate the effects of different nutritional regimens on the stress response in broilers. Hence, an experiment was conducted to examine the effects of sucrose and supplemental water electrolytes on Ross 308 male broilers during corticosterone-induced stress, as well as the particle grind size during poststress recovery. Feeding broilers supplemental water electrolytes during corticosterone-induced stress resulted in improved live performance. Feeding water sucrose to stressed broilers did not result in live performance improvements during the stress period. However, broilers fed water-sucrose or water-electrolyte treatments during the stress period had improved feed conversion during stress recovery. Feeding broilers a diet with increased particle size during stress recovery had no effect on live performance. Carcass measurements were not affected by any treatment. Water-electrolyte or water-sucrose supplements appear to have some potential as stress amelioration agents and thus should be researched more thoroughly.

Body Weight, Carcass Yield, and Intestinal Contents of Broilers Having Sodium and Potassium Salts in the Drinking Water Twenty-Four Hours Before Processing

SUMMARY The purpose of this study was to investigate the effects of drinking water supplementation with graded increases of Na and K salts on the performance and gut contents of broilers before processing. Birds had no water, tap water, or water supplemented with sodium bicarbonate or potassium chloride in the concentrations of 0.15, 0.30, and 0.45% in the last 12 and 24 h before processing. The last 12 h coincided with preslaughter feed withdrawal. Cobb × Cobb 500 male broilers (46 d old) were set in a completely randomized experimental design with 8 treatments and 9 replications of 9 birds each. Birds were individually processed within a period of 12 h of feed withdrawal every 2 h. Individual weighing was followed with electrical stunning and removal of intestinal contents of the upper (crop through the gizzard) and lower segment (duodenum through cloaca). Water intake increased linearly with greater salt concentrations in the water (P 0.05). It is concluded that increasing water intake through the use of Na and K salts did not affect the rate of gut emptying before processing.

Drinking water supplementation with ascorbate is not protective against UVR‐B‐induced cataract in the guinea pig

To study if ascorbate supplementation decreases ultraviolet radiation (UVR)-induced cataract development in the guinea pig. Sixty 6-9-week-old pigmented guinea pigs received drinking water supplemented with or without 5.5 mm l-ascorbate for 4 weeks. After supplementation, 40 animals were exposed unilaterally in vivo under anaesthesia to 80 kJ/m(2) UVR-B. One day later, the animals were killed and lenses were extracted. Degree of cataract was quantified by measurement of intensity of forward lens light scattering. Lens ascorbate concentration was determined with high-performance liquid chromatography (HPLC) with UVR detection at 254 nm. Twenty animals were used as non-exposed control. Supplementation increased lens ascorbate concentration significantly. In UVR-exposed animals, mean 95% confidence intervals (CIs) for animal-averaged lens ascorbate concentration (micromol/g wet weight lens) were 0.54 +/- 0.07 (no ascorbate) and 0.83 +/- 0.05 (5.5 mm ascorbate). In non-exposed control animals, mean 95% CIs for animal-averaged lens ascorbate concentration (micromol/g wet weight lens) were 0.72 +/- 0.12 (0 mm ascorbate) and 0.90 +/- 0.15 (5.5 mm ascorbate). All non-exposed lenses were devoid of cataract. Superficial anterior cataract developed in all UVR-exposed lenses. The lens light scattering was 39.2 +/- 14.1 milli transformed equivalent diazepam concentration (m(tEDC)) without and 35.9 +/- 14.0 m(tEDC) with ascorbate supplementation. Superficial anterior cataract develops in lenses exposed to UVR-B. Ascorbate supplementation is non-toxic to both UVR-B-exposed lenses and non-exposed control lenses. Ascorbate supplementation does not reduce in vivo lens forward light scattering secondary to UVR-B exposure in the guinea pig.

Multi-analyte approach for the determination of ng L−1 levels of steroid hormones in unidentified aqueous samples

Since the 1970s, many analytical methods for the detection of illegal growth promoters, such as thyreostats, anabolics, β-agonists and corticosteroids have been developed for a wide range of matrices of animal origin, including meat, fat, organ tissue, urine and faeces.The aim of this study was to develop an analytical method for the determination of ngL−1 levels of estrogens, gestagens, androgens (EGAs) and corticosteroids in aqueous preparations (i.e. drinking water, drinking water supplements), commercially available on the ‘black’ market. For this, extraction was performed with Bakerbond C18 speedisk, a technique commonly used in environmental analysis. After fractionation, four fractions were collected using a methanol:water gradient program. Gas chromatography coupled to electron impact multiple mass spectrometry (GC–EI-MS2) screening for the EGAs was carried out on the derivatized extracts. For the detection of corticosteroids, gas chromatography coupled to negative chemical ionization mass spectrometry (GC–NCI-MS) was used after oxidation of the extracts. Confirmation was done by liquid chromatography coupled to electrospray ionization multiple mass spectrometry (LC–ESI-MS2). The combined use of GC and LC coupled to MS enabled the identification and quantification of anabolics and corticosteroids at the low ngL−1 level. This study demonstrated the occurrence of both androgens and corticosteroids in different commercial aqueous samples.

Impact of blending reuse and lake water on treated water quality

The impact of supplementing a raw drinking water source with reuse water was examined. Reuse water produced from municipal wastewater by a membrane bioreactor and reverse osmosis (MBR-RO) system was blended with untreated Lake Ontario water, then subjected to conventional water treatment processes, and evaluated in terms of disinfection by-products (DBPs), nitrate, and coliforms. The addition of reuse water to the lake water improved water quality in terms of total organic carbon (TOC) and bromide, which resulted in reduced trihalomethane (THM) formation. This appeared to be entirely due to dilution with no specific impact from the conventional treatment process. Nitrate levels in the reuse water (1.4 mg/L) were higher than the lake water (0.4 mg/L) and, therefore, an increase in the reuse water : lake water blend ratio resulted in a linear increase in nitrate levels. The conventionally treated blend water was shown to meet typical drinking water regulations for THMs, haloacetic acids (HAAs), total coliform, and nitrate. Key words: water reuse, drinking water supplement, reverse osmosis, membrane bioreactor, conventional water treatment, disinfection by-products, nitrate.

Mycobacterial infections in cattle and pigs caused by Mycobacterium aviumcomplex members and atypical mycobacteria in theCzech Republicduring 2000-2004

Bovine tuberculosis was last detected in cattle and pigs in the CzechRepublicin 1995. Since March,&amp;nbsp;31, 2004(Commission Decision No. 2004/320/EC) the Czech Republichas been included amongst states free from bovine tuberculosis within the European Union. The purpose of the present study was to evaluate results of intravital and post-mortem diagnosis of mycobacterial infections in slaughtered cattle and pigs from 2000 to 2004. When bovine tuberculosis in cattle was investigated, a tuberculin skin test with bovine tuberculin was performed every year and a skin test with avian tuberculin was simultaneously conducted in the animals with a positive response. A total of 2 419 889 animals were examined with a positive response being found in 123 (0.005%) of them. After slaughter, bovine tuberculosis was not detected in any of these animals by gross and/or laboratory examinations. With avian tuberculin, 40&amp;nbsp;349 animals were tested and positive responses were detected in 43 (0.1%) of them; the incidence was similar in all the years monitored. Tuberculous lesions were detected in 209 (0.01%) of 1&amp;nbsp;967&amp;nbsp;211 slaughtered cattle. Mycobacteria were present in 40 (21.3%) of 188 animals examined by laboratory methods: 26&amp;nbsp;isolates of Mycobacterium avium subsp. avium (18 isolates of serotype 2 and 8 isolates not typeable), 11 isolates&amp;nbsp; of M. a. hominissuis (1 isolate of serotype 8 and 10 isolates not typeable), and 3 isolates of atypical mycobacteria. Tuberculous lesions were detected in 49 312 (0.22%) of 22 312 580 slaughtered pigs by veterinary-meat inspection. During the 5-year-period monitored, the incidence of tuberculous lesions decreased from 0.37% in 2000 to 0.10% in 2004. The following mycobacteria were isolated from 757 (33.5%) of 2&amp;nbsp;261 animals whose organs were examined by culture: 203 isolates of M. a. avium (180 isolates of serotype 2, 3 isolates of serotype 2/8, and 20 isolates not typeable), 442 isolates of M. a. hominissuis (1 isolate of serotype 1, 262 isolates of serotype 8, 35 isolates of serotype 9, 1 isolates of mixed serotypes 8/9, and 143 isolates not typeable), and atypical mycobacteria (n = 112). In both animal species, M.&amp;nbsp;avium complex members prevailed: M. a. avium was the most prevalent subspecies in cattle, M.&amp;nbsp;a.&amp;nbsp;hominissuis in pigs. The main sources of M. a. avium and M. a. hominissuis are free living birds and contaminated external and stable environments (i.e. drinking water, feeds, and feed supplements), respectively. During the entire period monitored, miliary or generalized tuberculosis was not detected in any of the animals. The decreased incidence of tuberculous lesions in pigs was particularly a result of preventive measures adopted to control the occurrence of atypical mycobacteria.

Ascorbate in the guinea pig lens: dependence on drinking water supplementation

To investigate whether lens ascorbate concentration can be elevated with drinking water supplementation. Pigmented guinea pigs received drinking water supplemented with L-ascorbate, concentration 0.00, 2.84, 5.68 or 8.52 mm for a duration of 4 weeks. In addition, the chow fed to all animals contained 125 mmol L-ascorbate per kg of chow. At the end of the supplementation period, the guinea pigs were killed. Each lens was extracted. The lens was processed and ascorbate concentration was measured using high performance liquid chromatography (HPLC) with 254 nm ultraviolet radiation detection. The data were analysed with regression. At the end of the test period, all lenses were devoid of cataract as observed by slit-lamp examination. All lenses contained a detectable concentration of ascorbate. Estimated 95% confidence intervals for mean animal-averaged lens ascorbate concentrations (micromol/g wet weight of whole lens) per group were 0.51 +/- 0.04 (0.00 mm; n = 6), 0.70 +/- 0.18 (2.84 mm; n = 6), 0.71 +/- 0.11 (5.68 mm; n = 5), and 0.71 +/- 0.06 (8.52 mm; n = 6). Animal-averaged lens ascorbate concentration [Asc(lens)] (micromol/g wet weight lens) increased with ascorbate supplementation in drinking water [Asc(water)] (M), in agreement with the model: [Asc(lens)] = A - Be(-kAsc(water)]. Lens ascorbate concentration increases with drinking water supplementation in the guinea pig without cataract development. The currently presented method for measurement of whole lens ascorbate content is suitable.

The impact of prebiotics and salmonellosis on apparent nutrient digestibility and Salmonella typhimurium var. Copenhagen excretion in adult pigeons (Columba livia domestica)

The effects of lactose or fructo-oligosaccharide (FOS) supplementation on the excretion of salmonellae, apparent digestibilities and excreta consistency were studied. Thirty-two male pigeons (Columba livia domestica) were randomly divided into 4 equal groups: 3 of 4 groups were orally infected with 10(9) Salmonella Typhimurium var. Copenhagen, after being offered a drinking water supplement of 2% FOS, 2% lactose, or no supplement, respectively, for 2 wk. Pigeons in the fourth group were not challenged with S. Typhimurium and remained unsupplemented. Initially, FOS increased water intake, resulting in more watery excreta. After infection, supplementation showed no major effects on S. Typhimurium excretion, nitrogen retention, or apparent nutrient digestibilities, although lactose–and to a lesser extent FOS–improved apparent fiber digestibility during recovery from the S. Typhimurium infection. The excreta consistency of all pigeons returned to normal when recovering from the Salmonella infection. In this trial, neither FOS nor lactose was successful in tempering the negative aspects of Salmonella infection in pigeons. Nevertheless, it should be stated that future investigations should clarify the importance of duration and level of prebiotic supplementation and infection level.

Glucose and electrolyte supplementation of drinking water improve the immune responses of poults with inanition

Enteric disorders predispose poultry to malnutrition. The objectives of this paper were 1) to simulate the inanition of poult enteritis mortality syndrome by restricting feed intake and 2) to develop a drinking water supplement that supports the immune functions of poults with inanition.Poults were restricted to 14 g of feed/d for 7 d beginning at 14 d of age then fed ad libitum until 36 d (recovery). The control was fed ad libitum. During the feed-restriction period, duplicate groups of 6 poults received 1 of 5 drinking water treatments: 1) restricted feed, unsupplemented water; 2) restricted feed + electrolytes (RE); 3) RE + glucose + citric acid (REGC); 4) REGC + betaine (REGCB); or 5) REGCB + zinc-methionine (REGCBZ). Immunological functions were assessed by inoculating poults with SRBC and B. abortus (BA) antigen at 15, 22, and 29 d of age. Antibody (Ab) titers were determined 7 d later for primary, secondary, and recovery responses. The primary and secondary total Ab titers to SRBC for restricted feed were 4.71 and 6.16 log3, which where lower (P < 0.05) than for controls (8.00 and 9.66 log3) and the other treatments. The recovery Ab titer for controls was 10.7, significantly higher than restricted feed (8.71) and RE (8.10) groups but not different from other treatments. The primary total Ab responses to BA were significantly lower in the restricted feed and RE groups as compared with the control and other treatments. Although feed restriction of poults to maintenance reduces the humoral immune responses, these responses can be significantly improved by drinking water containing electrolytes and especially sources of energy such as glucose and citric acid.

Effect of Administering Sodium Chlorate in Drinking Water on Salmonella Typhimurium Concentrations in Weaned and Finished Pigs

Salmonella can cause disease and compromise food safety. Consequently, strategies are sought to reduce colonization of food animals by these pathogens. Because Salmonella, like most enterobacteria, possesses respiratory nitrate reductase activity, which coincidentally reduces chlorate to cytotoxic chlorite, we hypothesized that chlorate may selectively kill these pathogens but not beneficial gut anaerobes lacking this activity. Whereas we have since shown that oral gavage of sodium chlorate to weaned pigs does kill Salmonella in the gut, we now report results from experiments evaluating the efficacy of administering chlorate in drinking water, which is a more practical application of this technology. In our first experiment, weaned pigs orally infected with 10 8 colony forming units (CFU) of a novobiocin and nalidixic acid resistant Salmonella Typhimurium were allowed ad libitum access 24 h later to drinking water containing either 0 (0X treatment) or 15 mM (1X treatment) sodium chlorate. In order to promote expression of respiratory nitrate reductase activity by Salmonella and to provide at least a minimum amount of available reductant, the drinking water treatments also contained 2.5 mM sodium nitrate and 20 mM sodium lactate. The pigs were euthanized 24 and 36 h after being allowed access to the drinking water treatments and gut contents collected at necropsy were cultured quantitatively for the challenge Salmonella strain via direct plating of serial ten-fold dilutions to Brilliant Green Agar (BGA) supplemented with 25 and 20 µg novobiocin and naladixic acid mL -1 , respectively. For enhanced sensitivity, the gut contents were also cultured qualitatively via initial enrichment in tetrathionate broth, further enrichment in Rappaport-Vassiliadis broth and selective differentiation on the antibiotic supplemented BGA. Incubation steps were performed at 37°C for 18 to 24 h. For the pigs provided 36 h access to the 1X chlorate treatment, cecal and rectal Salmonella concentrations were reduced (P 0.05) on water consumption (34 to 40 mL/kg body wt) was observed. These results demonstrate the practicality of administering sodium chlorate as a drinking water supplement to reduce gut concentrations of Salmonella in weaned and finished pigs.

L-arginine and antineutrophil serum enable venular control of capillary perfusion in hypercholesterolemic rats.

The purpose of this study was to investigate and counteract dysfunctional control of capillary flow in hypercholesterolemia. Capillary flow is controlled by arteriolar tone, which in turn is influenced by mediators released from closely paired venules in a mechanism that involves nitric oxide (NO). However, venular control of capillary flow is altered with hypercholesterolemia. Rats were given a normal or high-cholesterol diet before measurements of mesenteric capillary red blood cell velocity. The arteriolar pathway leading to the capillary was videotaped to measure the percent of the surrounding area (within 15 |gmm) that was occupied by a venule (% pairing). Venule-paired arterioles were significantly smaller in hypercholesterolemia compared with normocholesterolemia, corresponding to slower capillary flow. A positive correlation between capillary velocity and % pairing observed in normocholesterolemia was not observed during NO synthase inhibition or in hypercholesterolemic rats. However, positive correlations between the two parameters were found in hypercholesterolemia when the rats were given drinking water supplementation of L-arginine or an injection of antineutrophil serum, both of which tended to improve velocity in capillaries branching from venule-paired arteriolar pathways. Dysfunctional venular control of capillary perfusion in hypercholesterolemia may be a consequence of a neutrophil-mediated deficiency of NO.

L-Arginine and Antineutrophil Serum Enable Venular Control of Capillary Perfusion in Hypercholesterolemic Rats

Objective: The purpose of this study was to investigate and counteract dysfunctional control of capillary flow in hypercholesterolemia. Capillary flow is controlled by arteriolar tone, which in turn is influenced by mediators released from closely paired venules in a mechanism that involves nitric oxide (NO). However, venular control of capillary flow is altered with hypercholesterolemia. Methods: Rats were given a normal or high-cholesterol diet before measurements of mesenteric capillary red blood cell velocity. The arteriolar pathway leading to the capillary was videotaped to measure the percent of the surrounding area (within 15 µm) that was occupied by a venule (% pairing). Results: Venule-paired arterioles were significantly smaller in hypercholesterolemia compared with normocholesterolemia, corresponding to slower capillary flow. A positive correlation between capillary velocity and % pairing observed in normocholesterolemia was not observed during NO synthase inhibition or in hypercholesterolemic rats. However, positive correlations between the two parameters were found in hypercholesterolemia when the rats were given drinking water supplementation of L-arginine or an injection of antineutrophil serum, both of which tended to improve velocity in capillaries branching from venulepaired arteriolar pathways. Conclusions: Dysfunctional venular control of capillary perfusion in hypercholesterolemia may be a consequence of a neutrophil-mediated deficiency of NO.

Effects of growth factors and L-arginine on ischemic skin flaps in rats.

This study determined the effect of the polypeptide growth factors transforming growth factor-beta (TGF-beta), insulin-like growth factor-I (IGF-I), and growth hormone (GH) alone and in combination with dietary L-Arginine HCL (ARG) on skin flap survival in rats. Caudally based dorsal skin flaps were created in 110 Sprague-Dawley rats. The rats were randomly assigned into three treatment groups, based on drinking water supplementation. Group 1 (n = 50) received ARG in their drinking water, group 2 (n = 50) received tap water alone, and group 3 (n = 10) received N-omega-nitro-L-arginine (L-NA) and hydralazine. Groups 1 and 2 were divided into subgroups of 10 rats each based on treatment with either: TGF-beta, IGF-I, GH, or IGF-I + GH. All subgroups that received GH had significantly greater (P < .0001) median body weight gains when compared with subgroups not receiving GH. L-arginine HCL when added to IGF-I negated the positive effects of IGF-I on both flap survival and weight gain. Although the rats in all subgroups from groups 1 and 2 had an increase in mean percent skin flap survival when compared with the water alone subgroup, only rats receiving IGF-I, or the combination of ARG with either TGF-beta or GH, had statistically significant enhanced skin flap survival. Rats in group 3 did not show an increase in skin flap survival when compared with the control subgroup.

Drinking Water Temperature and Potassium Chloride Supplementation Effects on Broiler Body Temperature and Performance During Heat Stress

Four experiments were conducted to evaluate the effect of drinking water temperature and KCl supplementation on broiler performance during cycling temperature heat stress. Drenching birds with 12.8°C water reduced body temperature at a6 min post-drenching for 37°C (43 vs. 43.5), but not 24°C (43.5 vs. 43.5) exposed birds. Feed consumption and body weight gain improved as drinking water temperature declined from 43.3 to 10°C. Potassium chloride supplementation increased feed consumption and weight gain of birds offered cold water (P < .05). However, KCl supplementation of warm drinking water had no beneficial effect on feed consumption or weight gain. Body temperature rise during heat stress exposure was less (P < .05) for 10 vs. 43.3°C drinking water temperature and drinking water heat sink potential was positively correlated (P < .09) with gain, feed consumption, and gain/feed ratio.