Effects of Group and Individual Housing on the Behavior of Kennelled Dogs in Animal Shelters

Abstract

Recent findings have led researchers to believe that our pets may do more for us than we think. A dog's presence may even make a person appear more likable. Two studies were conducted to test this hypothesis. In the first study, 34 subjects viewed photographs of people pictured alone, pictured with a dog, and pictured with flowers. The subjects were asked to rate the person in the photos with regard to four dimensions: approachability, happy looking, relaxed looking, and best photo. The central finding revealed that photos of individuals pictured with a dog were rated higher than photos of individuals pictured without a dog. In the second study 45 subjects were asked to view three types of slides. The three slides consisted of outdoor scenery, a person walking through the outdoor scene, and a person walking a dog through the outdoor scene. Subjects were asked to rate the slides against each other with regard to several aesthetic dimensions, which included easiest to gaze at and best photo. In addition, subjects were asked how they perceived the person photographed with respect to happiness, relaxed looking, and safety. Finally, subjects were asked to choose photos in which they would like to be included. The major results of Study II demonstrated that (1) photos rated highest for questions concerning subjects' feelings toward the slides (easy to gaze at, feeling relaxed, best photo) were the scenery slides shown alone. The second highest rating went to the slides of the person walking the dog. (2) The person shown in the scene was perceived as appearing happier and safer when with the dog. (3) Subjects preferred to be added to the scene shown alone, without the dog. And when given the choice to replace the person shown, subjects preferred to replace the person in the scene with the dog rather than the person shown alone. Overall, results of both Studies I and II indicate that people appear happier, safer, and make a better “picture” when seen with a dog. Also, the results show that people appear more relaxed when sitting or standing with a dog. Finally, when asked to place themselves in the scene, subjects would rather be in a scene with a dog than alone.     

Effect of Visitor Perspective on Adoption Decisions at One Animal Shelter

This study investigated the visitor experience at one urban animal shelter. While several previous studies have examined the reasons particular nonhuman animals are chosen by adopters, few have investigated the possible reasons one would visit a shelter and leave without adopting. Over a two-month period, 158 visitors were surveyed after they were finished touring the shelter. One quarter of those exiting the shelter had adopted a pet (companion animal) compared to 11% who had been planning to adopt that day but did not. Almost 20% of survey respondents were just visiting with no plans for pet adoption either that day or in the near future. Being affectionate and friendly were important characteristics sought by potential adopters, although non-adopters reported more frequently than adopters that the animal’s reaction to them was important. Shelters should work toward increasing chances for pets to connect and interact with visitors and focus on educating and retaining the interest of those who are not quite ready for a new pet.     

Maternal Effects of Photoperiod and Food Level on Life History Characteristics of the Cladoceran Daphnia Pulicaria Forbes

The response of various life-history characteristics of Daphnia pulicaria to photoperiod and food concentration was measured in 16 combinations of maternal and offspring environments (long vs. short day, high vs. low food) in flow-through experiments. Response variables in offspring were time and survival to release of first offspring, clutch size and neonate mass in the first brood, mass of adult females after 30days and somatic growth rate during the course of the experiment. Most of these parameters were directly controlled by food concentration in the offspring environment, but maternal effects frequently modified the response. A long day length in the maternal environment resulted in a prolongation of the time to first clutch release in offspring similar to the direct effect of low food. Likewise, survival to maturation and female mass were affected by maternal photoperiod. Somatic growth rate and clutch size responded to combined effects of maternal food conditions and photoperiod. The laboratory results were used to predict the seasonal change of fecundity of Daphnia in the field. When data on clutch size are ordered in a sequence as the different combinations of maternal and offspring environment occur during the seasonal succession in a temperate lake, they show a bimodal distribution with a high peak in spring and a lower peak in fall. This pattern is consistent with field observations. We conclude that photoperiod and maternal effects are important factors influencing life history and population dynamics of Daphnia.     

Effects of chronic exercise on the kidneys at different ages

In order to determine the effects of chronic exercise on the kidneys at different ages, young, adult, and old rats swam 1 hour either daily or twice a week for 10 weeks and then were killed along with unexercised controls. The kidneys were removed and sections were prepared for histometric analysis including planimetric measurements on camera lucida drawings of renal components and line sampling. With both degrees of exercise young rats showed lower kidney weight, fewer glomeruli and less medullary tissue than unexercised controls. In the adult group no significant differences were noted between exercised and unexercised rats. In old rats both degrees of exercise resulted in a loss of kidney weight and medullary and cortical mass, and a decrease in size of glomeruli while total number of glomeruli remained unchanged. Thus the effects of chronic exercise on the kidneys varied with age. Retarded kidney development occurred in young animals; a loss of renal tissue in old animals; and no change in adult animals.     

Further Evidence for the Influence of Photoperiod at Birth on Chronotype in a Sample of German Adolescents

Individuals differ in their circadian preferences (chronotype). There is evidence in the literature to support a season-of-birth effect on chronotype but the evidence is not convincing. In part, the relationship is obscured by a number of methodological differences between studies, including the measures used to define morningness, the way in which the seasons were categorized, and the sample size. This study adds to the literature in several ways. First, we adopt a new approach to categorizing the photoperiod rather than the calendar season; thus we prefer to use the term photoperiod at birth. Second, we used two measures of morningness. Third, we used a large and homogeneous German sample. The results show that adolescents (n?=?2905) born during the increasing photoperiod (Feb–Apr) had a significantly later midpoint of sleep (MSFsc) than those born during the decreasing photoperiod (Aug–Oct). A similar pattern was found for the Composite Scale of Morningness (CSM). Furthermore, both measures of chronotype demonstrated a significant quadratic function over a 1-yr cycle. When looking at each of six consecutive years separately, the Composite Scale of Morningness suggests a cosine rhythm linked to increasing and decreasing photoperiods that becomes weaker in amplitude with increasing age. Despite the strengths in our study, the effect of photoperiod at birth on chronotype remains small. Future studies may require larger sample sizes, may need to explore how neonatal light exposure modulates chronotype, and may need to track how puberty and adolescent lifestyle habits mask the photoperiod effect. (Author correspondence: vollmer@ph-heidelberg.de)     

Effects of Two Types of Clothing on the Day-Night Variation of Core Temperature and Salivary Immunoglobulin a

Circadian variations in core temperature, skin temperatures, heart rate, and salivary immunoglobulin A (IgA) were compared in subjects wearing two different types of clothing that covered, or left uncovered, their extremities. The experiments were carried out on six female subjects at an ambient temperature of 24 ± 0.5°C and relative humidity of 50 ± 5%. One type of clotiiing consisted of long-sleeved shirts, full-length trousers, and socks (Type L: 1042 g, 1.048 clo); the other was half-sleeved shirts and knee-length trousers (Type H: 747 g, 0.744 clo). The main results were as follows: (i) The level of rectal temperature during night sleep was significantly lower with Type H than Type L clothing, and cosinor analysis indicated a significantly higher circadian amplitude with Type H clothing, (ii) Skin temperatures in the lower extremities increased significantly more on retiring to sleep with Type H than Type L clothing, (iii) Heart rate was significantly lower with Type H than Type L clothing during the sleep period, (iv) The day-night variation of salivary IgA showed a pattern that was the inverse of that of rectal temperature (i.e., low in the daytime and high in the nighttime), and the concentration of salivary IgA was significantly higher with Type H than Type L clothing at 02:30. (v) Subjectively, the self-assessed sleep quality was better with Type H clothing. These results suggest that clothing that leaves the extremities uncovered might be regarded as favorable at the moderate temperature since it induces good sleep and activates the immune response. (Chronobiology International, 14(6), 607–617, 1997)     

低强度激光对人红细胞生物物理特性的影响

研究不同功率的低强度He-Ne激光对正常人体红细胞流变学特性影响。以正常人体红细胞为研究对象,测量了低强度He-Ne激光在不同照射时间、不同功率条件下红细胞的变形、取向、膜流动性、膜的微粘度和渗透脆性的变化情况。结果表明:照射后红细胞的变形性和膜流动性增强、渗透脆性下降。照射对红细胞流变学特性影响显著,其中激光能量为0.24 J、照射血样为2 mL时取得的照射效果最佳。     

Effects of Glycosylation of the Residue at Position 14 in Ovine Angiotensinogen on the Human Renin Reaction

A mutant angiotensinogen, S14N, in which Ser¹⁴ of ovine angiotensinogen was replaced by Asn to form a N-glycosylation site, was produced in CHO cells. The molecular weight was about 3,000 larger than that of wild-type ovine angiotensinogen, indicating that S14N angiotensinogen was glycosylated at Asn¹⁴. In the reaction with human renin, the K _m of mutant angiotensinogen was 3 times increased, but the V _max was not affected by the mutation.     

不同温度下球孢白僵菌对桃蚜生殖力及生命表参数的影响

对6日龄桃蚜Myzus persicae(Sulzer)用106孢子/mL球孢白僵菌Beauveria bassiana(Balsamo)Vuillemin悬浮液接种后,饲养于4组温度(18,21,25和28℃)下,相对湿度(RH)为85%的条件下,观察其生殖力及生命表参数的变化。结果显示,与对照相比,在观察时限的10d内接种蚜日均产仔数分别减少43%,31%,53%和61%,接种蚜的净生殖力R0下降57%,73%,74%,60%,内禀增长力rm下降30%,41%,36%,22%。这表明,球孢白僵菌对桃蚜种群增长具有一定的抑制作用,其作用在21、25℃下更为明显。     

Dependence of the Phenotypic Characteristics of <Emphasis Type="Italic">Acidithiobacillus ferrooxidans</Emphasis> on the Physical,Chemical, and Electrophysical Properties of Pyrites

Comparison of Acidithiobacillus ferrooxidans strains TFV-1 and TFBk with respect to their capacity to oxidize pyrite 1, with an electron-type (n-type) conductivity, or pyrite 2, with hole-type (p-type) conductivity, showed that, at a pulp density of 1%, both before and after its adaptation to the pyrites, strain TFBk, isolated from a substrate with a more complex mineral composition, grew faster and oxidized the pyrites of both conductivity types more efficiently than strain TFV-1, which was isolated from a mineralogically simple ore. At a pulp density of 3–5%, the oxidation of pyrite 2 by strain TFV-1 and both of the pyrites by strain TFBk began only after an artificial increase in Eh to 600 mV. If the pulp density was increased gradually, strain TFBk could oxidize the pyrites at its higher values than strain TFV-1, with the rate of pyrite 2 oxidation being higher than that of pyrite 1. During chemical oxidation of both of the pyrites, an increase was observed in the absolute values of the coefficients of thermoelectromotive force (K_TEMF); during bacterial-chemical oxidation, the K_TEMF of pyrite 1 changed insignificantly, whereas the K_TEMF of pyrite 2 decreased.     

Effects of an autocorrelated stochastic environment and fisheries on the age at maturity of Chinook salmon

Chinook salmon (Oncorhynchus tshawytscha) reproduce only once in their lifetime, and their age at reproduction varies among individuals (indeterminate semelparous). However, the factors that determine their spawning age still remain uncertain. Evidence from recent studies suggests that individual growth and reproduction of Chinook salmon are affected by the rate of coastal upwelling, which is shown to be positively autocorrelated between years. Therefore, the serially autocorrelated environmental is expected to play an important role in determining their spawning age. In the present study, I demonstrate the advantage of an indeterminate maturation strategy under a stochastic environment. I then present theoretical evidence for the advantage of adjusting the maturation probability based on the environment they experienced and demonstrate that fisheries reduce the fitness of the strategy to delay maturation. The results presented herein emphasize the importance of incorporating detailed life-history strategies of organisms when undertaking population management.     

孕穗期低温对黑龙江省主栽水稻品种空壳率的影响

障碍型冷害对黑龙江省水稻生产影响巨大,明确主栽水稻品种耐冷性及障碍型冷害的量化指标,可为当地水稻安全生产提供科学依据。本文对黑龙江省4个主栽水稻品种(垦稻12、龙稻3号、龙稻7号和空育131)在孕穗期进行不同低温处理,分析了各处理对水稻空壳率的影响。结果表明:在平均温度为15℃时,孕穗期低温的持续天数是水稻形成障碍型冷害的关键因素;在低温持续时间相同的条件下,昼夜恒温15℃使各品种水稻受低温影响最严重;在不同低温处理条件下,不同品种水稻发生一般障碍型冷害的临界时长为1～4d或5～8d,发生严重障碍型冷害的临界时长为5～8d或8d以上,品种间临界时长有所差异;供试品种中,垦稻12和龙稻3号耐冷性较弱,空育131耐冷性较强,龙稻7号耐冷性居中。     

NaCl胁迫对红砂萌发的影响及萌发期耐盐性评价

探究盐胁迫对红砂种子萌发及萌发后生长和生理生化指标的影响,为解析红砂萌发期耐盐机制及后续研究提供数据支撑。以盐生植物红砂种子为试验材料,NaCl溶液模拟盐胁迫,研究不同浓度NaCl(0、50、100、150、200、300和400 mmol/L)处理下,红砂种子萌发及萌发后根长、株高、生理生化指标的变化趋势。结果显示:(1)与对照相比,50 mmol/L处理的红砂萌发率升高,植株根长、株高显著增加;随着处理浓度的升高,红砂的萌发时间推迟,萌发率减少,盐害率增加,根长、株高下降显著。当盐浓度增加到400 mmol/L时,红砂不能萌发,但仍保持萌发活力,400 mmol/L胁迫35 d的未萌发种子经复萌处理后,相对萌发率为105.43%。(2)随着NaCl浓度的增加,红砂中的丙二醛(MDA)、脯氨酸(Pro)含量显著增加,过氧化物酶(POD)、超氧化物歧化酶(SOD)活性呈现不同程度的增加。(3)分别以相对萌发率、植株全长下降到对照的50%为标准,确定红砂的萌发耐盐阈值为273 mmol/L,最适盐浓度为45.78 mmol/L;萌发后生长耐盐阈值为388.19 mmol/L,生长最适盐浓度为50.59 mmol/L。红砂可在胁迫环境下长期保持萌发活力,待萌发条件适宜时,可快速集中大量萌发;红砂生长阈值浓度大于萌发阈值浓度,说明萌发期是其在盐胁迫下完成生活史的关键时期;随着盐浓度的增加,红砂的生长受到不同程度的抑制,植株在一定胁迫程度内可通过提高POD、SOD活性清除MDA,增加Pro含量从而减少胁迫危害,以维持正常的生理代谢。     

Some Characteristics of a Peptidyl Dipeptidase (Kininase II) from Rat CSF: Differential Effects of NaC1 on the Sequential Degradation Steps of Bradykinin

Incubation of various authentic peptides with rat CSF in vitro and analysis of their products by HPLC demonstrated the presence in CSF of a peptidyl dipeptidase [peptidyl dipeptide hydrolase; angiotensin I converting enzyme (ACE); kininase II; EC 3.4.15.1] which sequentially degraded bradykinin (BK) by liberating the carboxy-terminal dipeptides and converted angiotensin I to angiotensin II. This CSF enzyme was gel-chromatographed by means of HPLC, and the molecular weight was estimated. The susceptibility to various peptidase inhibitors of the rat CSF enzyme, as well as the effect of NaCl on the degradation of BK and Hip-His-Leu catalyzed by it, was also determined. These properties were compared with those of ACE or kininase II from brain or other tissues, as described in the literature. NaCl was shown to exert specific and concentration-dependent effects on each step of the sequential degradation of BK, via BK(1-7) to BK(1-5), catalyzed by the enzyme. In addition, the enzyme system for metabolism of BK appears to differ between rat CSF and blood, the former containing exclusively kininase II, whereas the latter contains both kininase I (carboxypeptidase N; EC 3.4.12.7) and kininase II.     

Effects of Natural and Synthetic Auxins on the Gravitropic Growth Habit of Roots in Two Auxin-Resistant Mutants of Arabidopsis, axr1 and axr4: Evidence for Defects in the Auxin Influx Mechanism of axr4

Arabidopsis thaliana, axr4 , was restored by the addition of 30–300 nM 1-naphthaleneacetic acid (NAA) to the growth medium. Neither indole-3-acetic acid (IAA) nor 2,4-dichlorophenoxyacetic acid (2,4-D) showed such an effect. Growth of axr4 roots was resistant to IAA and 2,4-D, but not at all to NAA. The differential effects of the three auxins suggest that the defects of axr4 result from a lower auxin influx into its cells. The partially agravitropic growth habit of axr1 roots, which was less severe than that of axr4 roots, was only slightly affected by the three auxins in the growth medium at concentrations up to 300 nM; growth of axr1 roots was resistant to all three of the auxins. These results suggest that the lesion of axr1 mutants is different from that of axr4. Received 9 June 1999/ Accepted in revised form 16 August 1999     

Effects of hybrid and maturity on performance and nutritive characteristics of forage maize at high latitudes, estimated using the gas production technique

We evaluated effects of hybrid and advancing plant maturity on performance, chemical composition, and nutritional characteristics of whole plant forage maize as well as the relative contributions of its plant fractions at high latitudes. Three maize hybrids, Avenir (FAO 180), Isberi (FAO 190) and Burli (FAO 210), were grown in southern Sweden in a field experiment with a replicated complete randomized block design. Plants were harvested four times during maturation, and dry matter (DM) yield and DM as a proportion of fresh weight were recorded. Whole plants were separated into four morphological fractions representing stems, leaves, kernels and cobs and the contribution of each fraction to the DM of the whole plant was estimated. Plant material was subjected to chemical analysis followed by measurement of in vitro gas production (GP) in buffered rumen fluid and finally, by calculation of in vitro true digestibility of organic matter (OM) and neutral detergent fibre (aNDFom). The GP profiles were fitted to a first order kinetic model with a discrete lag. Parameters describing the GP profiles were used in a recently developed mechanistic two compartment rumen degradation model to estimate in vivo OM digestibility (OMD) and first order rate of degradation in the rumen. Hybrids were compared and effects of maturity were assessed by analysis of variance using DM concentration as covariate. There were differences (P<0.05) among the hybrids in DM yield and relative contributions of the plant fractions. Differences (P<0.05) in modelled in vivo digestibility of OM and rates of degradation also occurred among hybrids. Increased maturity caused a reduction in in vitro digestibility of aNDFom in all plant fractions (P<0.05), but increased the rate of rumen degradation of OM in the whole plant as evaluated from GP results. The DM yield had a quadratic relationship with increasing maturity, with maximum yield at a DM concentration of about 370 g/kg. In vitro GP can describe the nutritive characteristics of forage maize in relation to advancing maturity and increased maturity affected agronomic performance and plant composition as well as the nutritive characteristics of hybrids.