Morphological responses of woody species to simulated twig-browsing in Botswana

2004 ◽  
Vol 20 (3) ◽  
pp. 281-289 ◽  
Author(s):  
Tuulikki Rooke ◽  
Roger Bergström ◽  
Christina Skarpe ◽  
Kjell Danell
Keyword(s):  
Growth Rate ◽  
General Pattern ◽  
Woody Species ◽  
Ground Level ◽  
Shoot Biomass ◽  
Growth Responses ◽  
Treatment Groups ◽  
Lateral Shoots ◽  
Grewia Flava ◽  
Morphological Responses

Increased shoot growth has recurrently been recorded following real or simulated shoot browsing, although responses may vary between different woody species. We investigated morphological responses to simulated dry-season browsing on Colophospermum mopane, Acacia tortilis, Grewia flava, Peltophorum africanum and Ziziphus mucronata, which differ in growth rate, occurrence of spines and use by mammalian herbivores. Treatment groups included a control, four clipping intensities and cutting at ground level. Responses were monitored during the following growth season on three annual shoots, located in the bottom, middle and top height interval, on each sapling. All five species showed compensatory growth responses, although no obvious relation was found between the strength of responses and growth rate or natural browsing pressure. The general pattern was an increased shoot length, shoot diameter, number of lateral shoots and shoot biomass with increased clipping intensity. These responses are probably an effect of the reduction of competing growing points and disrupted apical dominance. Growth responses were stronger in shoots with higher location on the sapling, which may reflect the pressure on saplings to attain a certain height to avoid browsing, reproduce and increase resistance to fire. We found no evidence of the number of spines being an induced defence in either of the two spinescent species studied.

scholarly journals Growth Responses of Boreal Scots Pine, Norway Spruce and Silver Birch Seedlings to Simulated Climate Warming over Three Growing Seasons in a Controlled Field Experiment

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 943
Author(s):  
Katri Nissinen ◽  
Virpi Virjamo ◽  
Antti Kilpeläinen ◽  
Veli-Pekka Ikonen ◽  
Laura Pikkarainen ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Scots Pine ◽  
Root Biomass ◽  
Growing Season ◽  
Silver Birch ◽  
Shoot Biomass ◽  
Growth Responses ◽  
Growing Seasons ◽  
Simulated Climate ◽  
Shoot And Root Biomass

We studied the growth responses of boreal Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L. Karst.) and silver birch (Betula pendula Roth) seedlings to simulated climate warming of an average of 1.3 °C over the growing season in a controlled field experiment in central Finland. We had six replicate plots for elevated and ambient temperature for each tree species. The warming treatment lasted for the conifers for three growing seasons and for the birch two growing seasons. We measured the height and diameter growth of all the seedlings weekly during the growing season. The shoot and root biomass and their ratios were measured annually in one-third of seedlings harvested from each plot in autumn. After two growing seasons, the height, diameter and shoot biomass were 45%, 19% and 41% larger in silver birch seedlings under the warming treatment, but the root biomass was clearly less affected. After three growing seasons, the height, diameter, shoot and root biomass were under a warming treatment 39, 47, 189 and 113% greater in Scots pine, but the root:shoot ratio 29% lower, respectively. The corresponding responses of Norway spruce to warming were clearly smaller (e.g., shoot biomass 46% higher under a warming treatment). As a comparison, the relative response of height growth in silver birch was after two growing seasons equal to that measured in Scots pine after three growing seasons. Based on our findings, especially silver birch seedlings, but also Scots pine seedlings benefitted from warming, which should be taken into account in forest regeneration in the future.

Influence of energy and protein concentration in the diet on the performance of growing pigs 2. Differing nutrient density at a constant energy: protein ratio

1972 ◽  
Vol 14 (1) ◽  
pp. 47-55 ◽  
Author(s):  
G. A. Lodge ◽  
M. E. Cundy ◽  
R. Cooke ◽  
D. Lewis
Keyword(s):  
Growth Rate ◽  
Live Weight ◽  
Fat Content ◽  
Growing Pigs ◽  
Feed Conversion ◽  
Large White ◽  
Protein Ratio ◽  
Treatment Groups ◽  
Nutrient Density ◽  
Amino Acid Balance

SUMMARYForty-eight gilts by Landrace sires on Large White × Landrace females were randomly allocated to eight pens and within pens to six treatment groups involving three diets and two levels of feeding from 23 to 59 kg live weight. All diets were formulated to have approximately the same ratio of digestible energy to crude protein (160 kcal DE/unit % CP) but different energy and protein concentrations: (A) 3500 kcal/kg DE and 21 % CP, (B) 3150 kcal/kg DE and 19% CP, and (C) 2800 kcal/kg DE and 17% CP. Amino acid balance was maintained relatively constant with synthetic lysine, methionine and tryptophan. The levels of feeding were such that the lower level of diet A allowed an intake of energy and protein similar to the higher level of diet B, and the lower level of B was similar to the higher level of C.On the lower level of feeding, growth rate, efficiency of feed conversion and carcass fat content increased linearly with each increment in nutrient concentration; on the higher level of feeding growth rate and EFC increased from diet C to B but not from B to A, whereas carcass fat content increased linearly with diet from the lowest to the highest concentration. There was a non-significant tendency for the higher density diets at a similar level of nutrient intake to give better EFC and fatter carcasses than the lower density diets.

Canopy development and hydraulic function in Eucalyptus tereticornis grown in drought in CO2-enriched atmospheres

2007 ◽  
Vol 34 (12) ◽  
pp. 1137 ◽  
Author(s):  
Brian J. Atwell ◽  
Martin L. Henery ◽  
Gordon S. Rogers ◽  
Saman P. Seneweera ◽  
Marie Treadwell ◽  
...  
Keyword(s):  
Elevated Co2 ◽  
Shoot Growth ◽  
Co2 Enrichment ◽  
Atmospheric Co2 ◽  
Shoot Biomass ◽  
Eucalyptus Tereticornis ◽  
Growth Responses ◽  
Ambient Conditions ◽  
Long Distance ◽  
Pipe Model

We report on the relationship between growth, partitioning of shoot biomass and hydraulic development of Eucalyptus tereticornis Sm. grown in glasshouses for six months. Close coordination of stem vascular capacity and shoot architecture is vital for survival of eucalypts, especially as developing trees are increasingly subjected to spasmodic droughts and rising atmospheric CO2 levels. Trees were exposed to constant soil moisture deficits in 45 L pots (30–50% below field capacity), while atmospheric CO2 was raised to 700 μL CO2 L–1 in matched glasshouses using a hierarchical, multi-factorial design. Enrichment with CO2 stimulated shoot growth rates for 12–15 weeks in well-watered trees but after six months of CO2 enrichment, shoot biomasses were not significantly heavier (30% stimulation) in ambient conditions. By contrast, constant drought arrested shoot growth after 20 weeks under ambient conditions, whereas elevated CO2 sustained growth in drought and ultimately doubled the shoot biomass relative to ambient conditions. These growth responses were achieved through an enhancement of lateral branching up to 8-fold due to CO2 enrichment. In spite of larger transpiring canopies, CO2 enrichment also improved the daytime water status of leaves of droughted trees. Stem xylem development was highly regulated, with vessels per unit area and cross sectional area of xylem vessels in stems correlated inversely across all treatments. Furthermore, vessel numbers related to the numbers of leaves on lateral branches, broadly supporting predictions arising from Pipe Model Theory that the area of conducting tissue should correlate with leaf area. Diminished water use of trees in drought coincided with a population of narrower xylem vessels, constraining hydraulic capacity of stems. Commensurate with the positive effects of elevated CO2 on growth, development and leaf water relations of droughted trees, the capacity for long-distance water transport also increased.

scholarly journals The rooting, survival and growth of woody species on tailing dumps in the limestone quarry “Lafarge ciment”

2021 ◽  
Vol 13 (1(22)) ◽  
pp. 34-42
Author(s):  
Petru Cuza ◽  
◽  
Corina Certan ◽  
Constantin Bulimaga ◽  
◽  
...  
Keyword(s):  
Growth Rate ◽  
Environmental Factors ◽  
Slow Growth ◽  
Woody Species ◽  
Mineral Elements ◽  
Black Pine ◽  
Limestone Quarry ◽  
Survival And Growth ◽  
High Degree ◽  
Fast Growing Species

The rooting, the survival and dynamics of growths in the height and after the diameter of the seedlings, of a range of woody species, had investigated on the freshly formed sterile dump limestone quarry „Lafarge Ciment”. The seedlings of the woody species had a relatively good rooting (69-99%). A high degree of rooting can be ensured as a result of the maintenance of forest crops. After planting, the young seedlings must be cared for by hoeing as many times as necessary in order to control the weeds and maintain moisture in the soil, which increases the survival of the seedlings. Tree species have been characterized by a different growth rate. Acacia has showed a very rapid increase in height, but the black pine has been characterized by a slow growth. Acacia being a fast-growing species and unpretentious to the mineral elements in the soil can be used to afforest the limestone quarry land. In the fi rst year after planting, the young seedlings, otherwise sensitive to the action of the environmental factors, had an increase in height and in diameter slow and uneven. In the years that followed, the seedlings became more viable and less infl uenced by local and temporal fl uctuations of environmental factors.

scholarly journals Survival and growth responses of snakehead fish Channa striata Bloch. juvenile in aerated and unaerated acid sulfate water

2017 ◽  
Vol 16 (1) ◽  
pp. 60
Author(s):  
, Purnamawati ◽  
Daniel Djokosetiyanto ◽  
Kukuh Nirmala ◽  
Enang Harris ◽  
Ridwan Affandi
Keyword(s):  
Growth Rate ◽  
Blood Glucose ◽  
Specific Growth Rate ◽  
Feed Efficiency ◽  
Specific Growth ◽  
Stocking Density ◽  
Water Volume ◽  
Growth Responses ◽  
Acid Sulfate ◽  
Channa Striata

<p><strong>ABSTRACT </strong></p><p> </p><p>The aim of the research was to analyze survival rate, specific growth rate, albumin, and feed efficiency and physiological (blood glucose, cortisol, dan haemoglobin) responses of snake head fish juvenil that reared at aerated and unaerated of tidal land water have been conducted in the laboratory. Experiments using completely randomized design with aerated and unaerated as a treatment, and each treatment has twelve replications. The snakehead fish juvenil wich length 2.4±0.2 cm and weight of 0.21±0.05 g reared in the aquarium that are size 30×25×35 cm (water volume 25 L) with a stocking density 2 juvenile/L, for 40 days. The fishes were fed with commercial feed with protein content about 40%, feeding two times a day (morning and afternoon) were at satiation. Replacement of water done every two days about 10% of the total water volume in the aquarium. The results showed that unaerated median significantly affected to biometric and physiological response of juvenile of snake head fish. The media un-aerated gives the best results shown by the higher value of survival (92%), specific growth rate (6.73%/ day), feed efficiency (78.22%), protein retention (41.91%), energy retention (30.81%) value of albumin (6.60 g/100 mL) and the haemoglobin (5.58 g/dL), and have the lowest value of cortisol (21.49 ng/L) and blood glucose (43.36 mg/100 mL).</p><p> </p><p>Keywords: acid sulfate water, growth rate, aeration, <em>Channa striata </em></p><p><em> </em></p><p> </p><p><strong>ABSTRAK </strong></p><p> </p><p>Penelitian ini bertujuan untuk menganalisis respons kelangsungan hidup, pertumbuhan spesifik, albumin, dan efisiensi pakan dan fisiologis (kortisol, glukosa darah, dan hemoglobin) juvenil ikan gabus yang dipelihara dengan dan tanpa aerasi pada media air rawa pasang surut. Penelitian menggunakan rancangan acak lengkap dengan aerasi dan tanpa aerasi sebagai perlakuan, dan masing-masing perlakuan memiliki 12 ulangan. Juvenil ikan gabus berukuran panjang 2,4±0,3 cm dan bobot 0,21±0,03 g dipelihara dalam akuarium 30×25×35 cm (volume 25 L) dengan padat tebar 2 ekor/L, selama 40 hari. Ikan diberi pakan berupa pakan komersial dengan kadar protein ±40%, pemberian pakan dua kali sehari (pagi dan sore) <em>at satiation</em>. Penggantian air dan penyiponan dilakukan dua hari sekali sebanyak 10% dari volume total dalam akuarium. Hasil penelitian menunjukkan bahwa perlakuan tanpa aerasi berpengaruh nyata terhadap respons biometrik dan fisiologis juvenil ikan gabus. Media tanpa aerasi memberikan hasil yang lebih baik ditunjukkan oleh kelangsungan hidup (92%), laju pertumbuhan spesifik (6,73%/ hari), efisiensi pakan (78,22%), retensi protein (41,91%), retensi energi (30,81%), kadar albumin (6,60 g/100 mL), dan hemoglobin (5,85 g/dL) yang lebih tinggi, sedangkan kadar kortisol (219 ng/L) dan glukosa darah (43,36 mg/100 mL) yang terendah.</p><p> </p><p>Kata kunci: media sulfat masam, pertumbuhan, aerasi, <em>Channa striata</em></p>

scholarly journals Effect of Diatomaceous Earth on Growth Rate, Egg Production, Feed Conversion Efficiency and Parasitic Load in Hens Raised on Deep Litter

2021 ◽  
Vol 3 (1) ◽  
pp. 97-103
Author(s):  
Robert Alex Isabirye ◽  
Savino Biryomumaisho ◽  
James Okwee-Acai ◽  
Samuel Okello ◽  
George William Nasinyama
Keyword(s):  
Growth Rate ◽  
Conversion Efficiency ◽  
Egg Production ◽  
Diatomaceous Earth ◽  
Agricultural Research ◽  
Ascaridia Galli ◽  
Feed Conversion ◽  
Indigenous Chicken ◽  
Feed Conversion Efficiency ◽  
Treatment Groups

The efficacy of diatomaceous earth (DE) on growth rate, egg production and on increasing feed conversion efficiency in deep litter raised layer hens was evaluated. The study was conducted at Mukono Zonal Agricultural Research and Development Institute (MUZARDI) in Uganda. Worms were collected from fresh intestines of indigenous chicken obtained from Kalerwe chicken market near Kampala. The DE was mined in Pakwach (formerly Nebbi) district in Northern Uganda. Chickens of the Lohmann Brown breed raised on deep litter were studied. At 7 weeks the birds were divided into 5 treatment groups, A, B, C, D and E each composed of 40 birds. Groups C, D and E were given an oral dose containing 250 embryonated eggs of A. galli while groups A and B were not infected. The chicks were weighed; and subjected to feeding trials as arranged below: A – Non-infected birds on DE (4%) supplemented diet; B –non-infected birds on neither piperazine (a conventional de-wormer) nor DE; C – infected birds on DE supplemented diet; D – infected birds on piperazine; and group E – infected birds on neither DE nor piperazine applied. Fecal samples were collected and analysed in the laboratory biweekly at week 16 till week 22 respectively for fecal egg counts. In a subsequent experiment, day-old layer chicks from Lohmann Brown strain but different from those used in earlier experiments, were used to assess the effect of DE on egg production. At 17 weeks of age the 420 were divided as follows: 6 treatment groups each having 7 replicates and each replicate having 10 birds. This study showed that DE can be used successfully in growing pullet diets to correct nutritional mineral imbalance since it supplies more than 14 trace elements and other elements. Diatomaceous earth also enables pullets to cope with Ascaridia galli load; and 2% DE supplementation did not have significant improvement on egg production as compared to no supplementation at all. However, reduction in egg production was experienced when supplementation with levels of DE higher that 2% was applied. Results from biweekly fecal analyses showed significant differences in fecal egg counts (p<0.05); and treatment by group (p<0.05).

Effects of simulated acid rain on the growth of five Brazilian tree species and anatomy of the most sensitive species (Joannesia princeps)

2005 ◽  
Vol 53 (8) ◽  
pp. 789 ◽  
Author(s):  
Luzimar Campos da Silva ◽  
Aristéa Alves Azevedo ◽  
Eldo Antônio Monteiro da Silva ◽  
Marco Antonio Oliva
Keyword(s):  
Acid Rain ◽  
Tree Species ◽  
Leaf Blade ◽  
Woody Species ◽  
Leaf Damage ◽  
Growth Responses ◽  
Foliar Injury ◽  
Sensitive Species ◽  
Abaxial Epidermis

Seedlings and young saplings of some woody species were exposed to simulated low-pH acid rain, in order to develop a response screening for tropical tree species by determination of the symptoms of foliar injury and growth responses, as well as to identify anatomical alterations in the leaf blade of the most sensitive species. Gallesia integrifolia (Spreng.) Harms, Genipa americana L., Joannesia princeps Vell., Mimosa artemisiana Heringer & Paula and Spondias dulcis Forst.f. were exposed daily to 20 min of acid rain, pH 3.0, for 10 consecutive days. The degree of leaf damage and the anatomical alterations observed were efficient parameters to determine the sensitivity to acid rain. At the end of the experiment J. princeps was the most sensitive species as determined by foliar injury and seedling growth. The degree of leaf damage was similar among the seedlings, except in S. dulcis, which showed reduced percentage of foliar injury. Necrotic and chlorotic spots on the leaf blade occurred. In the most sensitive species, J. princeps, necrotic blade tissues showed accumulation of phenolic compounds, hypertrophy and collapsed cells. Most of the structural alterations were observed in the adaxial epidermis, the palisade parenchyma and spongy parenchyma and the abaxial epidermis. Long-term experiments with seedlings of S. dulcis and saplings of G. integrifolia are suggested, to characterise the response of these species that presented fewer symptoms but whose growth was affected under acid rain.

Relocation does not have a significant effect on the growth rate of Bos indicus cross steers

2008 ◽  
Vol 48 (5) ◽  
pp. 608 ◽  
Author(s):  
R. G. Holroyd ◽  
V. J. Doogan ◽  
M. R. Jeffery ◽  
J. A. Lindsay ◽  
B. K. Venus ◽  
...  
Keyword(s):  
Growth Rate ◽  
Phase 1 ◽  
Bos Indicus ◽  
Poor Performance ◽  
The Other ◽  
Control Group ◽  
Phase 2 ◽  
Treatment Groups ◽  
Normal Ranges ◽  
Native Pastures

This experiment tested the hypothesis that relocating cattle is detrimental to their growth. The study examined the effect of having relocated cattle mixed with, or segregated from, the local acclimatised cattle at the destination property. Bos indicus cross steers (120) were allocated to three groups and were relocated, in two separate cohorts, 980 km from northern Queensland to improved pastures in central Queensland. At the start of Phase 1, the control group (C) was moved 3 months before the other two groups. The remaining two groups grazed native pastures; one group was supplemented (SR) to increase growth rate similar to that expected from improved pasture in central Queensland and the other was not supplemented (R). At the end of Phase 1, C was significantly (P < 0.05) heavier than SR, which was significantly (P < 0.05) heavier than R. At the start of Phase 2, the SR and R groups were relocated and after transportation the R and SR groups lost 12 kg or 4.4% of liveweight and 18 kg or 5.7% of liveweight, respectively; this weight loss was recovered after 5 days. All steers were reallocated to segregated (SEG) or mixed (MIX) treatment groups forming six treatments (SEG.C, SEG.R and SEG.SR and MIX.C, MIX.R and MIX.SR). There were no significant differences in liveweights within the SEG treatments by 57 days or within the MIX treatments by 106 days after relocation. There were few if any significant differences in the plasma constituents and differential leucocyte counts of the steers and most results were within physiologically normal ranges. We conclude on the basis of these results and of other experiments that the anecdotal poor performance of cattle after relocation appears to be unfounded.

Modeling and Predicting the Growth Boundary of Listeria monocytogenes in Lightly Preserved Seafood

2007 ◽  
Vol 70 (1) ◽  
pp. 70-84 ◽  
Author(s):  
OLE MEJLHOLM ◽  
PAW DALGAARD
Keyword(s):  
Growth Rate ◽  
Listeria Monocytogenes ◽  
Antimicrobial Effect ◽  
Growth Responses ◽  
Greenland Halibut ◽  
Critical Control Points ◽  
Smoked Salmon ◽  
Challenge Tests ◽  
Boundary Model ◽  
Fail Safe

The antimicrobial effect of diacetate and lactate against Listeria monocytogenes was evaluated in challenge tests with vacuum-packaged or modified atmosphere packaged (MAP) cold-smoked salmon, marinated salmon, cold-smoked Greenland halibut, marinated Greenland halibut, and gravad salmon. MAP cold-smoked salmon with the addition of 0.15% (wt/wt) diacetate prevented the growth of L. monocytogenes for more than 40 days at 8°C, whereas the addition of 0.15% (wt/wt) diacetate reduced the growth rate of the pathogen in MAP cold-smoked Greenland halibut. This difference between the two types of products was explained by a higher content of naturally occurring lactate in cold-smoked salmon (0.77 to 0.98%, wt/wt) than in cold-smoked Greenland halibut (0.10 to 0.15%, wt/wt). In fact, the addition of 0.15% (wt/wt) diacetate and 0.75% (wt/wt) lactate to MAP cold-smoked Greenland halibut prevented the growth of L. monocytogenes for more than 45 days at 8°C. A mathematical model that included the effect of diacetate, lactate, CO2, smoke components, nitrite, pH, NaCl, temperature, and interactions between all these parameters was developed to predict the growth boundary of L. monocytogenes in lightly preserved seafood. The developed growth boundary model accurately predicted growth and no-growth responses in 68 of 71 examined experiments from the present study as well as from literature data. Growth was predicted for three batches of naturally contaminated cold-smoked salmon when a no-growth response was actually observed, indicating that the model is fail-safe. The developed model predicts both the growth boundary and growth rate of L. monocytogenes and seems useful for the risk management of lightly preserved seafood. Particularly, the model facilitates the identification of product characteristics required to prevent the growth of L. monocytogenes, thereby making it possible to identify critical control points, and is useful for compliance with the new European Union regulation on ready-to-eat foods (EC 2073/2005).

Anti-Müllerian hormone reduces growth rate without altering follicular survival in isolated caprine preantral follicles cultured in vitro

2017 ◽  
Vol 29 (6) ◽  
pp. 1144 ◽  
Author(s):  
R. M. P. Rocha ◽  
L. F. Lima ◽  
I. R. Brito ◽  
G. M. Silva ◽  
H. H. V. Correia ◽  
...  
Keyword(s):  
Growth Rate ◽  
Cytochrome P450 ◽  
Hormone Receptors ◽  
Mrna Levels ◽  
Follicular Growth ◽  
Steroid Secretion ◽  
Preantral Follicles ◽  
Treatment Groups ◽  
Cytochrome P450 Family

The aim of the present study was to evaluate the effect of anti-Müllerian hormone (AMH), with and without FSH, on the in vitro development of isolated caprine preantral follicles, as well as follicular steroid production and mRNA levels of AMH, hormone receptors (AMH and FSH), CYP19A1 (cytochrome P450, family 19, subfamily A, polypeptide 1), CYP17 (cytochrome P450, family 17, subfamily A, polypeptide 1), HSD3B (3-beta-hydroxysteroid dehydrogenase) and Myc (myelocytomatosis oncogene). Isolated secondary follicles were cultured in minimum essential medium alpha (α-MEM+) alone or supplemented with 50 ng mL–1 AMH and/or 100 ng mL–1 FSH added sequentially on different days of culture. Follicles were cultured for a total of 18 days, with different media during the first (Days 0–9) and second (Days 10–18) halves of the culture period, resulting in six treatment groups, as follows: α-MEM+/α-MEM+, FSH/FSH, AMH/AMH, AMH+FSH/AMH+FSH, AMH/FSH, and FSH/AMH. Follicle development was evaluated on the basis of follicular growth, oocyte maturation and steroid secretion. There was a decrease in follicular growth rate in the AMH, AMH + FSH and AMH/FSH treatment groups compared with α-MEM+ and FSH treatment groups (P < 0.05). However, the different culture conditions had no effect on rates of meiotic resumption and steroid secretion (P > 0.05). Moreover, follicles cultured in the presence of FSH had lower levels of AMH receptor type II (AMHRII) mRNA compared with non-cultured control (freshly isolated follicles), and the AMH and AMH/FSH treatment groups. In conclusion, AMH reduces the follicular growth rate of isolated goat preantral follicles in vitro without affecting follicular survival.

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