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Taste responses in sheep
This study involved the use of the two-choice preference test,
where the choices were tap water and tap water-chemical solutions,
to determine the responses of sheep to ascending concentrations of
20 chemicals (taste stimulants). The chemicals tested were: the
sugars, sucrose, maltose, lactose, glucose, fructose and galactose;
the sodium salts of chloride, acetate (NaAc), propionate (NaPr) and
butyrate (NaBu); the acids, hydrochloric, acetic (HAc), propionic
(HPr), butyric (HBu) and lactic (HLa); and, quinine hydrochloride
(QHC1), urea, sodium saccharin, sodium hydroxide and ethanol.
Each sheep was individually penned and fed to appetite. Responses
were expressed on the basis of percent intake (that is, the
percent that the amount of test fluid consumed was of total fluid intake
for a given time period). Three groups of ten sheep. each
were used successively, the groups being divided into two units of
five animals and these units then being placed on alternate concentrations
of a test chemical. The mean responses of the units of five sheep were plotted
graphically and analyzed by the linear regression technique when
definite rejection trends were apparent. The chemical concentrations
at the acceptance and rejection thresholds (that is, where the
test chemical comprised 40% and 20% of total fluid intake, respectively)
were estimated from the regression line. When rejection
trends did not occur the responses were assessed on the basis of
their position relative to the non-discrimination zone. The nondiscrimination
zone was described as that zone where the test fluid
comprised not less than 40% nor more than 60% of total fluid intake.
It was derived by determining the normal variation, with tap water
in both containers, around a theoretical mean intake of 50% from
each container.
The responses to the sugars were, generally, of an indifferent
nature. One unit of animals displayed a. moderately strong preference
(79. 2% of intake) for sucrose at the . 1461 M concentration while
another unit was indifferent to the sugar at that concentration. A
weak preference (69.0% of intake) occurred for glucose at the . 2775 M
concentration. These were the only positive preferences observed
for any of the test chemicals. Moderate degrees of rejection were
manifested for sucrose concentrations above . 4382.M and for maltose
concentrations above. 0028 M. The pattern of the responses to sodium
saccharin was similar to that of the sugars: indifference at lower
and intermediate concentrations and moderate degrees of rejection
at higher concentrations.
The acceptance and rejection thresholds for NaC1 were at concentrations
of . 0429 M and . 3764 M, respectively. The thresholds
for NaAc were similar to those for NaC1. NaPr and NaBu had lower
threshold concentrations than NaCl and NaAc-.-possibly because of
smell.
The threshold concentrations and pH's obtained for HAc were:
acceptance, . 0024 M, pH of 4. 2; rejection, . 0276 M, pH of 3. 4. The
thresholds for HC1 were at lower concentrations and lower pH's than
for HAc. HPr and HBu were discriminated against at lower concentrations
and higher pH's than was HAc--possibly due 'to smell. The
concentrations at the acceptance and rejection thresholds of NaOH
were, respectively, .0036 M ('pH 11. 5) and .0132 M (pH 12. 0). A
comparison of these values with those for HC1 indicates that sheep
are more tolerant of highly alkaline pH's than of highly acid pH's.
QHC1 elicited acceptance and rejection threshold concentrations
of. 00048 M and . 0037 M, respectively. The responses to
urea were highly variable, but appreciable intake was observed at
concentrations of .4163 and 8325 M,
The thresholds for ethyl alcohol were at higher concentrations
than for any other of the test chemicals, sucrose and glucose being the
exceptions. The acceptance threshold for ethanol was at a
concentration of. 2621 M and the rejection threshold was at 1. 422 M.
With respect to glucose, NaC1, HAc and QHC1, the sensitivity
series for the four primary taste groups, in order of increasing
sensitivity, was: sweet, salty, sour and bitter. However, after
comparing the threshold values derived in this study for the sheep
to values reported for the goat and calf, the conclusions can be made
that the sheep is relatively indifferent to sweet tasting substances
and relatively tolerant to bitter tasting substances.
Considerable individual variation existed in the taste responses
exhibited by the sheep used in this study
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A comparison of taste responses in pygmy goats, normal goats, sheep and cattle
This study involved the use of the two-choice preference test
to determine the taste responses of eight, each, of pygmy goats,
normal goats, sheep and cattle to ascending concentrations of sucrose
(Suc), sodium chloride (NaC1), acetic acid (HAc) and quinine
hydrochloride (QHCI). In addition, sheep and cattle were tested at
2. 08 and 8. 33% molasses concentrations.
Each animal was individually penned and fed to appetite on a
nutritionally adequate diet. Responses were expressed on the basis
of percent of total fluid intake comprised by test. solution. Goats were
allowed two-day test periods per concentration; sheep and cattle
were given one-day test periods.
Mean responses and standard deviations of the eight-animal
groups were plotted graphically and compared to threshold levels of
intake. Response trends were analyzed by stepwise multiple linear
regression. A 95% confidence interval was established for a theoretical
mean intake of 50%. The upper confidence limit was at 60% intake
and the lower was at 40% intake. They were termed, respectively,
upper discrimination threshold (UPT) and lower discrimination
threshold (LDT). The rejection threshold (RET) was set at 20%
intake and the preference threshold (PRT) at 80% intake. Ascending
or descending responses at the various threshold concentrations
were identified by and , respectively.
Molar concentrations of thresholds crossed by responses of
pygmies, normals, sheep and cattle, respectively, were for Suc,
UDT; .055t and .53k; UDT: .033t, PRT: .38t; LDT: .41;
UDT: OZSt and . 4U, PRT: . 058f and .24, LDT: . 56; for
NaC1, UDT: .024t and .Z1, PRT; .iot and ,14, LDT: .36L
RET: , 60; UDT: . 0Z7, LDT: . 15L RET: . 55; LDT: .21,
RET: . 53 ; LDT: , 016, RET: , 14; for MAc, UDT: . 0034t
and .04Z, LDT: .l6, RET: > ZZ; LDT: .014, RET: .11;
UDT: .0034t, LDT: .028, RET: .094; UDT: .0017t and
.0069j, LDT: ,014, RET: .038'; and, for QHCL, UDT: >
.000016t and .000047,, LDT: .00030, RET: .00202; UDT:
.000016t and .000063, LDT: .00035, RET: .0020Z; LDT:
,000094, RET: .00035k; LDT: .00013 , RET: .000381.
In general, stimulating effectiveness was greatest for bitter,
followed in order by sour, salty and sweet. Cattle were usually first
to make a discrimination, goats were generally second and sheep
were normally last. The major exception was for the bitter taste
group where the order was goats, sheep, cattle. As a rule, goats
were more tolerant of high concentrations than were sheep and sheep
were more tolerant than cattle. The exception was, again, the bitter
taste group where the order was goats, cattle, sheep.
Sheep were indifferent to 2. 08 and 8. 33% molasses concentrations.
Cattle demonstrated stroxg preference respoises to the
2. 08% level and weak preference reactions to the 8.33% level
Heart Rate Responses during Simulated Fire Ground Scenarios among Full-Time Firefighters
International Journal of Exercise Science 13(2): 374-382, 2020. Simulated fire ground scenarios (SFGS) provide firefighters with an opportunity to maintain skills, receive feedback, and optimize performance. Although there is extensive research on heart rate (HR) changes in the firefighter population, few examine the differences between positions. Firefighters are primarily responsible for fire suppression and control (23), officers for emergency operations and organizational management, paramedics for providing on-scene emergency medical care, and drivers are responsible for driving the fire apparatus. Utilizing HR analysis to quantify the physical demands of SFGS among firefighting crews by position. Sixty-seven male (age: 38.97 ± 9.17; ht: 177.99 ± 6.45 cm. wt: 88.83 ± 13.55 kg) firefighters (FF) participated in this investigation. FF crews performed two SFGS involving the suppression and control of a structural fire. Participants were outfitted with heart rate (HR) monitors and average heart rate (HRavg) and maximum heart rate (HRmax) data were collected for each of the two SFGS. Significant differences were observed for Age (P = 0.01), APMHR (P = 0.01), HRmax1(P = 0.04), and HRmax2(P = 0.04) in which firefighters had higher values for Age-predicted maximal heart rate (APMHR), HRmax1, HRmax2compared to the officers. SFGS can be very physically demanding events that may elicit maximal or near maximal HR responses regardless of position. Based on the metabolic demands of these events and the individual firefighter’s capabilities, this information can be used to develop resistance training and conditioning programs that optimize performance at maximal or near maximal heart rates
Progress in dark tourism and thanatourism research: An uneasy relationship with heritage tourism
This paper reviews academic research into dark tourism and thanatourism over the 1996–2016 period. The aims of this paper are threefold. First, it reviews the evolution of the concepts of dark tourism and thanatourism, highlighting similarities and differences between them. Second it evaluates progress in 6 key themes and debates. These are: issues of the definition and scope of the concepts; ethical issues associated with such forms of tourism; the political and ideological dimensions of dark tourism and thanatourism; the nature of demand for places of death and suffering; the management of such places; and the methods of research used for investigating such tourism. Third, research gaps and issues that demand fuller scrutiny are identified. The paper argues that two decades of research have not convincingly demonstrated that dark tourism and thanatourism are distinct forms of tourism, and in many ways they appear to be little different from heritage tourism
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The philosophical foundations of participatory democracy: natural, human, critical
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