Deprivation is an environmental experience that organisms are continually exposed to. However, few studies analyze deprivation effects on the consumption pattern during the post-deprivation period systematically. The ...Deprivation is an environmental experience that organisms are continually exposed to. However, few studies analyze deprivation effects on the consumption pattern during the post-deprivation period systematically. The aim of this study was to evaluate the deprivation effect on feeding pattern, growth rate and body weight during post-deprivation. Sixteen albino rats (3 months old at the beginning of the experiment) were exposed to 72-hour total food deprivation every 15 days. Food and water were freely available during non-deprivation periods. Rats completed three cycles comprised by a free access period followed by food deprivation. Once deprivation was removed, food and water consumption increased and then decreased, while body weight was recovered. Growth rate increased after every deprivation period and reached similar levels to those presented by the control group. Depriving rats from one commodity (i.e., food) cause them to restrain their consumption of the other freely available commodity (i.e., water). Results confirm that food deprivation modifies growth rate, water and food consumption. Additionally, during post-deprivation period, differences between males and females were not registered.展开更多
This study determined effects of birth weights (0.70 to 1.09, 1.10 to 1.49, 1.50 to 1.89, and ≥ 1.90 kg) on the efficiency of milk utilization for growth in sow-reared piglets. One-hundred-sixty piglets from 18 mul...This study determined effects of birth weights (0.70 to 1.09, 1.10 to 1.49, 1.50 to 1.89, and ≥ 1.90 kg) on the efficiency of milk utilization for growth in sow-reared piglets. One-hundred-sixty piglets from 18 multiparous sows ( Landrace × Large White) were individually weighed immediately after birth ( day 0) and at 7-day intervals for 35 days. Milk consumption of piglets was determined weekly using the weigh-suckle-weigh method. Deaths of piglets were recorded daily. Piglets with the lightest birth weight had the highest incidence of mortality. Birth weights between 0.70 and 1.89 kg were positively as- sociated with average dally gains (ADG, g/day ) during the suckling period ( P 〈 0.01 ). Compared with piglets having birth weights of 1.50 to 1.89 kg, birth weights ≥ 1.90 kg did not confer any additional benefit on preweaning survival or ADG. Colostrum or milk consumption per kilogram of body weight among low-, normal-, and large-birth-weight piglets did not differ in the first week. At days 14 to 35, milk consumption of piglets ( g/kg BW/day ) increased (e 〈 0. 01 ) but the ratio of gain to milk consumption decreased ( P 〈 0.01 ) progressively, as their birth weights increased from 0.70 to ≥1.90 kg. Additionally, surviving low-birth-weight piglets had a higher relative growth rate (%/day ) than normal-and large-birth- weight piglets. Based on these novel findings, it is imperative that great efforts be made to improve the survival of low-birth-weight piglets so as to increase the efficiency of nutrient utilization by both lactating sows and suckling piglets.展开更多
The effects of sulfur dioxide(SO_2) on the dry weight growth gas exchange rate and leaf sulfur content of massion pine(Pinus massoniana Lamb. )were investigated. The results obtained in this study show that the dry we...The effects of sulfur dioxide(SO_2) on the dry weight growth gas exchange rate and leaf sulfur content of massion pine(Pinus massoniana Lamb. )were investigated. The results obtained in this study show that the dry weight growth and net photosynthetic rate of masson pine seedlings are reduced by exposure to SO_2 at ≥100 ppb. From these results,one of the main causes in the dieback of masson pine forest reported in Chongqing,China may be relatively high concentrations of atmospheric SO_2 in the relevant area.展开更多
The US Department of Energy is currently building strategies for the expansion of clean and renewable energy sources, and tall, rapidly-growing grasses such as giant miscanthus (Miscanthus × giganteus) and giant ...The US Department of Energy is currently building strategies for the expansion of clean and renewable energy sources, and tall, rapidly-growing grasses such as giant miscanthus (Miscanthus × giganteus) and giant reed (Arundo donax) are two of the many of species that could fill this renewable energy niche. The objective was to compare stalk growth components of giant miscanthus and giant reed, in a low-input system (no irrigation and no fertilizer use) in Arkansas, USA. Due to the potential invasiveness of giant reed, our study was conducted on an upland site to minimize escape. Plant height and dry weight per stalk were measured every week for two consecutive growing seasons in 2012 and 2013. Leaf area index (LAI) was measured every two weeks from May to September in 2012. A significant species × day interaction occurred for plant height and dry weight per stalk, due to the relatively greater height and weight of giant reed compared to giant miscanthus after May. Stalk elongation rate was greater for giant reed than giant miscanthus (1.85 and 1.11 cm day-1, respectively). Leaf area index differed between species, giant reed (10.4 m2 m-2) > giant miscanthus (4.4 m2 m-2). We showed that giant reed produced taller, heavier stalks, and had a greater stalk elongation rate, compared to giant miscanthus. For sustainable bioenergy production from giant reed in Arkansas, further studies should be performed to determine ideal number of harvests per year and associated production cost.展开更多
Background: Depression is the most prevalent psychiatric disorder in pregnancy and it is associated with psychosocial and obstetric factors. Studies have shown that pregnancy does not prevent women from becoming depre...Background: Depression is the most prevalent psychiatric disorder in pregnancy and it is associated with psychosocial and obstetric factors. Studies have shown that pregnancy does not prevent women from becoming depressed;rather, it may be a time when depression occurs for the first time in some women. Antenatal depression has been identified as a risk factor for post natal depression, adverse obstetric outcomes, poorer neonatal outcomes and higher growth retardation in infants. Purpose: This study aimed to determine the fetal growth outcomes among depressed pregnant women in their third trimester attending antenatal clinic at the Jos University Teaching Hospital (JUTH), Jos, Plateau State, Nigeria. Method: A prospective cohort study design was used to assess 514 women who consented to the study (256 cases and 258 controls). A socio-demographic questionnaire was given to the women to fill out the study entry. Edinburgh Post Natal Depression Scale (EPDS) was used to screen for depression and MINI neuropsychiatric interviews were used to diagnose depression in those women found to be at risk of depression using the EPDS. Ultrasonography was used to determine the fetal weight in the third trimester of pregnancy. The birth weight of the babies born to the women was obtained from the birth register in the labor ward and the fetal growth rate was calculated from the estimated fetal weight on ultrasound scan in late pregnancy and the birth weight of babies. Result: The mean fetal weight in the third trimester for non-depressed women was slightly higher than in depressed women though the difference was not statistically significant (P = 0.431). The difference in the mean calculated fetal growth rate for fetuses of non-depressed women in the third trimester was statistically significantly higher than in depressed women (p = 0.000). Depressed women also had babies with lower birth weight than non-depressed women and the difference was statistically significant (p = 0.00).展开更多
文摘Deprivation is an environmental experience that organisms are continually exposed to. However, few studies analyze deprivation effects on the consumption pattern during the post-deprivation period systematically. The aim of this study was to evaluate the deprivation effect on feeding pattern, growth rate and body weight during post-deprivation. Sixteen albino rats (3 months old at the beginning of the experiment) were exposed to 72-hour total food deprivation every 15 days. Food and water were freely available during non-deprivation periods. Rats completed three cycles comprised by a free access period followed by food deprivation. Once deprivation was removed, food and water consumption increased and then decreased, while body weight was recovered. Growth rate increased after every deprivation period and reached similar levels to those presented by the control group. Depriving rats from one commodity (i.e., food) cause them to restrain their consumption of the other freely available commodity (i.e., water). Results confirm that food deprivation modifies growth rate, water and food consumption. Additionally, during post-deprivation period, differences between males and females were not registered.
基金supported by funds from Agriculture and Food Research Initiative Competitive Grants no.2008-35206-187642008-35203-19120 from the USDA National Institute of Food and AgricultureTexas AgriLife Research Hatch project (H-8200), and Texas A&M University (College Station, Texas, USA)
文摘This study determined effects of birth weights (0.70 to 1.09, 1.10 to 1.49, 1.50 to 1.89, and ≥ 1.90 kg) on the efficiency of milk utilization for growth in sow-reared piglets. One-hundred-sixty piglets from 18 multiparous sows ( Landrace × Large White) were individually weighed immediately after birth ( day 0) and at 7-day intervals for 35 days. Milk consumption of piglets was determined weekly using the weigh-suckle-weigh method. Deaths of piglets were recorded daily. Piglets with the lightest birth weight had the highest incidence of mortality. Birth weights between 0.70 and 1.89 kg were positively as- sociated with average dally gains (ADG, g/day ) during the suckling period ( P 〈 0.01 ). Compared with piglets having birth weights of 1.50 to 1.89 kg, birth weights ≥ 1.90 kg did not confer any additional benefit on preweaning survival or ADG. Colostrum or milk consumption per kilogram of body weight among low-, normal-, and large-birth-weight piglets did not differ in the first week. At days 14 to 35, milk consumption of piglets ( g/kg BW/day ) increased (e 〈 0. 01 ) but the ratio of gain to milk consumption decreased ( P 〈 0.01 ) progressively, as their birth weights increased from 0.70 to ≥1.90 kg. Additionally, surviving low-birth-weight piglets had a higher relative growth rate (%/day ) than normal-and large-birth- weight piglets. Based on these novel findings, it is imperative that great efforts be made to improve the survival of low-birth-weight piglets so as to increase the efficiency of nutrient utilization by both lactating sows and suckling piglets.
文摘The effects of sulfur dioxide(SO_2) on the dry weight growth gas exchange rate and leaf sulfur content of massion pine(Pinus massoniana Lamb. )were investigated. The results obtained in this study show that the dry weight growth and net photosynthetic rate of masson pine seedlings are reduced by exposure to SO_2 at ≥100 ppb. From these results,one of the main causes in the dieback of masson pine forest reported in Chongqing,China may be relatively high concentrations of atmospheric SO_2 in the relevant area.
文摘The US Department of Energy is currently building strategies for the expansion of clean and renewable energy sources, and tall, rapidly-growing grasses such as giant miscanthus (Miscanthus × giganteus) and giant reed (Arundo donax) are two of the many of species that could fill this renewable energy niche. The objective was to compare stalk growth components of giant miscanthus and giant reed, in a low-input system (no irrigation and no fertilizer use) in Arkansas, USA. Due to the potential invasiveness of giant reed, our study was conducted on an upland site to minimize escape. Plant height and dry weight per stalk were measured every week for two consecutive growing seasons in 2012 and 2013. Leaf area index (LAI) was measured every two weeks from May to September in 2012. A significant species × day interaction occurred for plant height and dry weight per stalk, due to the relatively greater height and weight of giant reed compared to giant miscanthus after May. Stalk elongation rate was greater for giant reed than giant miscanthus (1.85 and 1.11 cm day-1, respectively). Leaf area index differed between species, giant reed (10.4 m2 m-2) > giant miscanthus (4.4 m2 m-2). We showed that giant reed produced taller, heavier stalks, and had a greater stalk elongation rate, compared to giant miscanthus. For sustainable bioenergy production from giant reed in Arkansas, further studies should be performed to determine ideal number of harvests per year and associated production cost.
文摘Background: Depression is the most prevalent psychiatric disorder in pregnancy and it is associated with psychosocial and obstetric factors. Studies have shown that pregnancy does not prevent women from becoming depressed;rather, it may be a time when depression occurs for the first time in some women. Antenatal depression has been identified as a risk factor for post natal depression, adverse obstetric outcomes, poorer neonatal outcomes and higher growth retardation in infants. Purpose: This study aimed to determine the fetal growth outcomes among depressed pregnant women in their third trimester attending antenatal clinic at the Jos University Teaching Hospital (JUTH), Jos, Plateau State, Nigeria. Method: A prospective cohort study design was used to assess 514 women who consented to the study (256 cases and 258 controls). A socio-demographic questionnaire was given to the women to fill out the study entry. Edinburgh Post Natal Depression Scale (EPDS) was used to screen for depression and MINI neuropsychiatric interviews were used to diagnose depression in those women found to be at risk of depression using the EPDS. Ultrasonography was used to determine the fetal weight in the third trimester of pregnancy. The birth weight of the babies born to the women was obtained from the birth register in the labor ward and the fetal growth rate was calculated from the estimated fetal weight on ultrasound scan in late pregnancy and the birth weight of babies. Result: The mean fetal weight in the third trimester for non-depressed women was slightly higher than in depressed women though the difference was not statistically significant (P = 0.431). The difference in the mean calculated fetal growth rate for fetuses of non-depressed women in the third trimester was statistically significantly higher than in depressed women (p = 0.000). Depressed women also had babies with lower birth weight than non-depressed women and the difference was statistically significant (p = 0.00).