scholarly journals Do African savanna elephants (Loxodonta africana) eat crops because they crave micronutrients?

2019 ◽  
Author(s):  
Susanne Marieke Vogel ◽  
Willem Frederik de Boer ◽  
Moses Masake ◽  
Anna Catherine Songhurst ◽  
Graham McCulloch ◽  
...  
Keyword(s):  
Mixture Models ◽  
Dry Matter ◽  
Phosphorus Deficiency ◽  
Dry Matter Intake ◽  
List Type ◽  
Negative Consequences ◽  
Digestible Energy ◽  
Food Items ◽  
Dietary Choices

AbstractElephants can cause negative consequences for both themselves and for humans by consuming agricultural crops. It is unclear whether savanna elephant crop consumption is merely opportunistic behaviour or related to insufficient quality of natural forage. We analysed the role of vegetation quality on elephant crop consumption. We focused on the role of micronutrients, as natural elephant diets are thought to be insufficient in elements such as sodium and phosporus, which can influence their foraging decisions.For 12 months across four seasons we collected elephant feeding trail data along with tree, grass and crop samples. We investigated how the quality and availability of these items influenced elephant dietary choices across months and seasons. Subsequently, we compared levels of fibre, digestible energy, dry matter intake, and micronutrients, together with secondary compounds (tannins) across the three vegetation groups. As elephants do not make dietary choices based on one component, we also analysed the nutrient balance of food items with right-angle mixture models.The levels of phosphorus, magnesium and dry matter intake corresponded to foraging preference. Compared to trees and grasses, crops contained significantly higher amounts of digestible energy content, dry matter intake, nitrogen, phosphorus, calcium and magnesium. PCA results showed that crops differed in phosphorus and magnesium levels. The right-angle mixture models indicated that except for one tree species, all food items elephants consumed were relatively deficient in phosphorus.The combined results of these analyses suggest a phosphorus deficiency in elephant diet in northern Botswana. Crops, with their high absolute phosphorus levels and dry matter intake, provide an alternative source of phosphorus to reduce the deficiency. This may explain the high intensity of crop consumption in the wet season in our study area. A potential mitigation measure against elephant crop consumption might be to provide supplementary phosphorus sources.

scholarly journals A simple and fast sampling method for chemical analyses and densitometry of bones through rib biopsies in cattle

2017 ◽  
Vol 37 (1) ◽  
pp. 31-35 ◽  
Author(s):  
Pedro Malafaia ◽  
Yury T.G. Salcedo ◽  
Ricardo A.R. Uscategui ◽  
Vinícius C. Souza ◽  
Diogo Fleury A. Costa ◽  
...  
Keyword(s):  
Weight Gain ◽  
Chemical Analysis ◽  
Dry Matter ◽  
Phosphorus Deficiency ◽  
Postoperative Recovery ◽  
Dry Matter Intake ◽  
Daily Weight Gain ◽  
Control Group ◽  
Average Daily Weight Gain ◽  
Simple Method

ABSTRACT: We developed and evaluated a fast and simple method to obtain suitable bone samples for densitometry and chemical analysis through biopsies of the 12th rib of cattle. The postoperative recovery, dry matter intake (DMI) and average daily weight gain (ADG) was evaluated in 36 Nellore steers, nine of which were randomly selected for the control group and 27 others were rib biopsied. Every 30 days, rib biopsy was performed in nine steers, using a corded-electric pistol-grip drill coupled with a hole saw of a 3mm diameter pilot drill bit. This rib biopsy technique provided a suitable sample obtained in a fast way and allowed the surgeon to work alone with the animal slightly sedated and restrained in the crush. Dry matter intake (DMI) was not affected in biopsied animals. At the end of the experimental period (116 days) the average daily weight gain (ADG) was similar in the steers biopsied or not. The described method provided rib samples from cattle suitable for densitometry and chemical analysis of bone tissue without effects on health and performance. This information could greatly increase the accuracy for the diagnosis of phosphorus deficiency in cattle raised on pasture and allow the evaluation of bone metabolism in experimental animals.

Requirement for phosphorus in rainbow trout (oncorhynchus mykiss) growing from 50 to 200 g

1995 ◽  
Vol 31 (10) ◽  
pp. 137-141 ◽  
Author(s):  
M. Rodehutscord ◽  
E. Pfeffer
Keyword(s):  
Rainbow Trout ◽  
Dry Matter ◽  
Dry Matter Intake ◽  
Feed Conversion ◽  
Exponential Functions ◽  
Digestible Energy ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
P Concentration ◽  
Dietary Concentration ◽  
Potential Maximum

Semi-purified diets containing 19.6 MJ digestible energy/kg dry matter were fed to groups of rainbow trout initially weighing, on average, 53 g/trout. In a series of 12 diets, mono sodium phosphate replaced a silica carrier aiming at a range in P concentration from 1.0 to 10.9 g/kg dry matter. Each diet was fed to a group of 20 trout. During the trial of 53 feeding days, response of dry matter intake, weight gain, feed conversion ratio and P concentration of the gain followed exponential functions. For achieving 95 % of the potential maximum gain, a dietary concentration of 3.7 g P per kg dry matter was required. However, 5.3 g P per kg dry matter were required for achieving high P concentration in the gain. P was utilized most efficiently at a dietary concentration of 2.5 g/kg dry matter. A dietary P concentration of 0.25 g available P per MJ digestible energy was recommended to be sufficient for trout diets.

The influence of dietary protein and energy concentration on the growth of Merino weaner sheep

1980 ◽  
Vol 20 (104) ◽  
pp. 308 ◽  
Author(s):  
BA McGregor ◽  
JW McLaughlin
Keyword(s):  
Dry Matter ◽  
Nitrogen Retention ◽  
Dry Matter Intake ◽  
Energy Concentration ◽  
Digestible Energy ◽  
Treatment Groups ◽  
Wool Growth ◽  
Dietary Concentration ◽  
Energy Retention ◽  
Total Body

The influence of the dietary concentration of protein and energy on the growth of Merino wether weaners in pens, was studied in a factorial experiment. There were two digestible energy concentrations, (12.4 and 14.2 MJ DE kg-1 DM) x five protein concentrations (9-21% CP), three replicates (each of one animal). Diets were offered ad libitum, and nitrogen and energy retention were determined by the comparative slaughter technique. Initially, the mean weight of all treatment groups was 15.5 kg liveweight (12 weeks of age), and the experiment concluded 14 weeks later. Daily dry matter intake, liveweight gain, wool growth and total body nitrogen retention increased linearly as dietary crude protein concentration increased. Higher energy concentrations reduced dry matter intake and liveweight gain, and increased wool growth. Approximately 21 % of the digestible energy intake was retained. Regressions relating carcase and non-carcase composition to compartment weight, are presented. The fastest and most efficient gain in liveweight occurred with the ration containing 20% CP, at the lower energy concentration. It is suggested that for high levels of production with Merino weaners, rations should contain at least 18% CP.

COMPOSITION CHIMIQUE, DIGESTIBILITE ET INGESTION VOLONTAIRE D’ENSILAGES D’HERBES ET DE MAIS PAR DES AGNEAUX

1976 ◽  
Vol 56 (1) ◽  
pp. 65-72 ◽  
Author(s):  
G. PELLETIER ◽  
J.-C. ST-PIERRE ◽  
J. E. COMEAU
Keyword(s):  
Dry Matter ◽  
Nutritive Value ◽  
Corn Silage ◽  
Dry Matter Intake ◽  
Composition Chimique ◽  
Digestible Energy ◽  
Stages Of Growth ◽  
Grass Silage ◽  
Voluntary Intake

Chemical analysis, in vivo digestibility and voluntary intake measurements were used to determine the nutritive value of different crops made as silage for sheep. In the first experiment, grass silages contained less N-NH3 than corn–pea silage. Digestible energy intake of grass silage treated with formic acid was higher than that which was untreated. Digestibility, dry matter intake and the nutritive value index were higher for corn–pea silage than for treated or untreated grass silage. In the second experiment, six different silages were made. Corn was harvested at the milk and dough stages of growth and after a frost and was chopped at either 1.3 cm or 0.6 cm. Silage made with corn harvested after a frost and chopped at 1.3 cm and that made with corn harvested at the milk stage and chopped at 0.6 cm had higher N-NH3 content than the others. Fine chopping decreased digestibility of silages harvested at earlier maturity stages but increased the digestible energy of the corn silage harvested after a frost. Voluntary intake was greater with silages harvested at the later dates than with silage harvested at the milk stage.

Digestion characteristics of two forms of preserved lucerne forage fed to mature horses

2012 ◽  
Vol 1 ◽  
Author(s):  
L. A. Waldron ◽  
D. G. Thomas ◽  
I. Pryor
Keyword(s):  
New Zealand ◽  
Energy Intake ◽  
Water Intake ◽  
Reference Values ◽  
Dry Matter ◽  
Dry Matter Intake ◽  
Small Scale ◽  
Digestible Energy ◽  
Thoroughbred Horses ◽  
Nutritional Benefits

SummaryA trial was conducted, using 12 mature thoroughbred horses as a cross-over design, to compare the water and energy intake and the digestibility of dry lucerne chaff (LC) against a controlled fermented lucerne (CFL) product (HNF Fiber®; Fiber Fresh Feeds Ltd, Reporoa, New Zealand). Significant (P < 0.05) increases in dry matter intake (20%), energy intake (20%), retained energy (32%) and digestible energy (22%) were observed for the CFL compared to the LC. In a concurrent small scale study within the trial, numeric improvements in water intake (18%) for the CFL were recorded. The results demonstrated that the standard reference values underestimate the digestibility and nutritional contribution made by CFL when fed to horses, and that this type of forage has increased nutritional benefits.

Food and Energy Consumption in Rodents from Different Environments: The Role of Photoperiod in Seasonal Acclimatization

1993 ◽  
Vol 27 (7-8) ◽  
pp. 505-510 ◽  
Author(s):  
A. Haim ◽  
A. Rubal
Keyword(s):  
Dry Matter ◽  
Rodent Species ◽  
Dry Matter Intake ◽  
Apodemus Flavicollis ◽  
Seasonal Acclimatization ◽  
Ambient Temperatures ◽  
Mediterranean Habitats ◽  
Gross Energy ◽  
Different Response

In several rodent species, changes in photoperiod are important signals for seasonal acclimatization of thermoregulatory mechanisms. Nocturnal rodents inhabiting extremely hot and arid areas like the Arava (Israeli Rift Valley), may be exposed to very low ambient temperatures, which may be far below their lower critical point. In contrast, nocturnal species from the mesic Mediterranean habitats are not exposed to such dramatic seasonal changes. In the present study, food consumption was measured as apparent digestible dry matter intake (DDMI), while energy was measured as digestible gross energy intake (DGEI), in four rodent species from different habitats. The studied mice were kept under two different photoperiod regimes 16L:8D long photophase, 8L:16D long scotophase at a constant ambient temperature (T =28°C). In Meriones crassus, which inhabits extremely arid habitats, apparent DDMI and DGEI were significantly higher in long scotophase acclimated individuals when compared with long photophase acclimated. However, in the mesic species Apodemus flavicollis these parameters were similar under acclimation to the two different photoperiod regimes. These results suggest that, in seasonal acclimatization, species from different habitats may have a different response to photoperiodic cues.

scholarly journals Can nitrogen-fertilised ryegrass substitute for white clover?

2002 ◽  
pp. 205-209 ◽  
Author(s):  
G.P. Cosgrove ◽  
C.B. Anderson ◽  
A.J. Parsons ◽  
J.L. Brock ◽  
J.C. Tilbrook
Keyword(s):  
White Clover ◽  
Dry Matter ◽  
Food Preference ◽  
Dry Matter Intake ◽  
High Concentration ◽  
Mixed Species ◽  
Low Concentration ◽  
N Concentration ◽  
Grazing Behaviour

Sheep and cattle have difficulty satisfying their preference for white clover when it's proportion in pastures is low. We tested the hypothesis that they prefer clover because it has a higher concentration of nitrogen (N), and expected that they would reduce their preference for clover (increase their preference for grass) when grass had a higher concentration of N. In two experiments, mature sheep and growing cattle were offered choices between grass, having either a high or a low concentration of N, and white clover, growing as adjacent pure swards. To test the specific role of N in preference they were also offered each grass alone (sheep only) and a choice between the high and low N grass. Sheep and cattle preferred clover (75% of time grazing on clover and 25% on grass), but this preference was not affected by the concentration of N in the grass. They preferred the grass with a high concentration of N to that with a low concentration. Sheep and cattle detect differences in the N concentration of food items, but alter their grazing behaviour (express a preference) only when it does not affect dry matter intake or the proportion of clover in their diet. We conclude that N is not the reason why animals prefer white clover. Manipulating the N concentration in grass will not cause the switch in preference required for animals to easily satisfy their preference from typical mixed species pastures that are grass-dominant and have a low proportion of clover. Keywords: cattle, diet selection, food preference, grazing behaviour, nitrogen, sheep

The effect of silage dry matter content and protein supplementation on the intake and performance of housed store lambs

1984 ◽  
Vol 1984 ◽  
pp. 12-12
Author(s):  
C R Stone ◽  
M Appleton
Keyword(s):  
Dry Matter ◽  
Matter Content ◽  
Protein Supplementation ◽  
The Other ◽  
Dry Matter Intake ◽  
List Type ◽  
Dry Matter Content ◽  
Factors Affecting ◽  
Ad Libitum ◽  
And Performance

Silage based diets fed to store lambs have often produced unsatisfactory growth rates. The factors affecting silage dry matter intake and the utilisation of silage by store lambs are not clearly understood.In each of two years 1981/2 and 1982/3 spring born store lambs (initial liveweight 31 kg) were housed from October until January. Three types of silage were fed ad-libitum:-1. Unwilted + additive (UN + A).2. Wilted + additive (W + A).3. Wilted without additive (W).Two groups of 23 lambs were fed on each type of silage; one group without supplementation (Nil) and the other at 60 g white fishmeal per lamb per day (WFM).

The effect of concentrate, barley and dried grass on the voluntary intake of different silages

1977 ◽  
Vol 24 (3) ◽  
pp. 393-400
Author(s):  
W. A. McIlmoyle ◽  
J. C. Murdoch
Keyword(s):  
Energy Intake ◽  
Dry Matter ◽  
Live Weight ◽  
Dry Matter Intake ◽  
Digestible Energy ◽  
Voluntary Intake ◽  
Barley Silage

SUMMARYIn two experiments with steers (initial live weight 339 kg) the effect of dried grass, barley and concentrates on the intake of ‘wilted’ and unwilted grass and whole-crop barley silage was investigated.In both experiments there was no significant effect of silage type on silage dry-matter intake when given alone or with a supplement. In Experiment 1, supplementation significantly reduced (P<0·05) the intake of silage dry matter (DM) from unwilted and whole-crop barley silage. Total DM intake was significantly higher (P<0·05) for the ‘wilted’ silage diet than for either the unwilted or whole-crop barley silage diets. In Experiment 2, supplementation had no significant effect on total DM intake. Digestible energy intake was significantly higher (P < 0·05) from whole-crop barley silage supplemented with concentrate rather than barley or dried grass and was significantly lower (P<0·05) from unwilted silage diets (P<0·05) when dried grass rather than concentrate or barley was given. In the second experiment, ration digestibility and rate of passage of digesta results are reported.

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