New perspectives on the mineral nutrition of livestock grazing cereal and canola crops

2016 ◽  
Vol 56 (8) ◽  
pp. 1350 ◽  
Author(s):  
H. Dove ◽  
D. G. Masters ◽  
A. N. Thompson

The grazing of cereal and canola crops during winter is an increasing component of grazing systems in southern Australia. The capacity of such crops to meet the requirements of young livestock and reproducing animals for sodium (Na), magnesium (Mg), calcium (Ca) and potassium (K) is reviewed. The growth responses of young stock to Na and/or Mg supplements when grazing wheat are discussed. These responses differ from ‘literature expectation’ in that they are rapid in onset and involve no clinical signs. We demonstrate that more insight about the variability in supplement response, both between and between crops species, is obtained when mineral contents are viewed from the perspective of their frequency distributions, rather than their mean values. The pivotal importance of high K concentration, low Na and the resultant K : Na ratio of forage is stressed, as is the interaction of these minerals in relation to Mg absorption. We also present frequency distributions for a range of mineral indices that ‘capture’ mineral interactions, including the ‘tetany index’, forage K :  (Na+Mg) ratio and dietary cation–anion difference. It is concluded that the last two indices warrant a much closer investigation. Possible effects of forage aluminium and organic acid contents are briefly discussed; these also deserve closer examination. As research in this area continues, it would be prudent to provide Na and/or Mg supplements for livestock grazing wheat and possibly oats and barley, and calcium supplements for livestock grazing oats or for reproducing animals grazing all three cereals.

2016 ◽  
Vol 56 (9) ◽  
pp. 1560
Author(s):  
H. Dove ◽  
D. G. Masters ◽  
A. N. Thompson

The grazing of cereal and canola crops during winter is an increasing component of grazing systems in southern Australia. The capacity of such crops to meet the requirements of young livestock and reproducing animals for sodium (Na), magnesium (Mg), calcium (Ca) and potassium (K) is reviewed. The growth responses of young stock to Na and/or Mg supplements when grazing wheat are discussed. These responses differ from ‘literature expectation' in that they are rapid in onset and involve no clinical signs. We demonstrate that more insight about the variability in supplement response, both between and between crops species, is obtained when mineral contents are viewed from the perspective of their frequency distributions, rather than their mean values. The pivotal importance of high K concentration, low Na and the resultant K:Na ratio of forage is stressed, as is the interaction of these minerals in relation to Mg absorption. We also present frequency distributions for a range of mineral indices that ‘capture' mineral interactions, including the ‘tetany index', forage K: (Na+Mg) ratio and dietary cation–anion difference. It is concluded that the last two indices warrant a much closer investigation. Possible effects of forage aluminium and organic acid contents are briefly discussed; these also deserve closer examination. As research in this area continues, it would be prudent to provide Na and/or Mg supplements for livestock grazing wheat and possibly oats and barley, and calcium supplements for livestock grazing oats or for reproducing animals grazing all three cereals.


Author(s):  
Cesar D. Fermin ◽  
Hans-Peter Zenner

Contraction of outer and inner hair cells (OHC&IHC) in the Organ of Corti (OC) of the inner ear is necessary for sound transduction. Getting at HC in vivo preparations is difficult. Thus, isolated HCs have been used to study OHC properties. Even though viability has been shown in isolated (iOHC) preparations by good responses to current and cationic stimulation, the contribution of adjoining cells can not be explained with iOHC preparations. This study was undertaken to examine changes in the OHC after expossure of the OHC to high concentrations of potassium (K) and sodium (Na), by carefully immersing the OC in either artifical endolymph or perilymph. After K and Na exposure, OCs were fixed with 3% glutaraldehyde, post-fixed in osmium, separated into base, middle and apex and embedded in Araldite™. One μm thick sections were prepared for analysis with the light and E.M. Cross sectional areas were measured with Bioquant™ software.Potassium and sodium both cause isolated guinea pig OHC to contract. In vivo high K concentration may cause uncontrolled and sustained contractions that could contribute to Meniere's disease. The behavior of OHC in the vivo setting might be very different from that of iOHC. We show here changes of the cell cytosol and cisterns caused by K and Na to OHC in situs. The table below shows results from cross sectional area measurements of OHC from OC that were exposed to either K or Na. As one would expect, from the anatomical arrangement of the OC, OHC#l that are supported by rigid tissue would probably be displaced (move) less than those OHC located away from the pillar. Surprisingly, cells in the middle turn of the cochlea changed their surface areas more than those at either end of the cochlea. Moreover, changes in surface area do not seem to differ between K and Na treated OCs.


Author(s):  
P. R. Chavelikar ◽  
G. and Neha Rao C. Mandali ◽  
Neha Rao

Ruminal acidosis is an important clinical emergency in small ruminants. In this study, eight healthy farm goats and 24 goats presented at TVCC of the college of Veterinary Sciences and A.H., Anand with clinical signs of ruminal acidosis and having rumen liquor pH below 6 were examined for alterations in the ruminal fluid and serum biochemical parameters. Among various rumen fluid parameters evaluated, the mean values of rumen fluid pH decreased significantly (4.71±0.11 vs. 6.90±0.10), while sediment activity time (46.67±1.20 vs. 24.50±0.78 min) and methylene blue reduction time (29.50±0.73 vs. 10.03±0.27 min) increased significantly in acidotic goats. The normal greenish, aromatic viscous color, odour and consistency of rumen fluid of healthy goats also changed to milky grey/creamy, sour/pungent watery in acidotic goats. The rumen protozoal activity decreased to nil in acidotic goats as compared to the healthy goats. Among various serum biochemical constituents, the mean values of glucose (92.43±1.37 vs. 74.13±1.83 mg/dl), BUN (26.49±0.47 vs. 22.63±1.19 mg/dl), serum creatinine (01.01±0.02 vs. 00.83±0.02 mg/dl) and albumin (03.22±0.03 vs. 03.05±0.05 g/dl), ALT (56.75±1.55 vs. 27.88±1.14 IU/L) and AST (93.25±1.82 vs. 54.00±1.75 IU/L), increased significantly, while there was significant decrease in serum calcium (09.09±0.14 vs. 10.29±0.08 mg/dl) in acidotic goats. The mean values of alkaline phosphatase (IU/L) in acidotic goats increased non-significantly from the base values of healthy goats.


Author(s):  
P. R. Chavelikar ◽  
G. C. Mandali ◽  
D. M. Patel

Ruminal acidosis is one of the most important clinical emergencies in sheep and goats resulting into high mortality rate. In the present study, eight healthy farm goats and 24 goats presented to the TVCC of the college with clinical signs of ruminal acidosis like anorexia, tympany, increased pulse and respiratory rate, reduced body temperature, doughy rumen, enteritis, oliguria, grinding of teeth, purulent nasal discharge, muscle twitching, arched back, dehydration and recumbency with rumen liquor pH below 6 were examined for haematological alterations using autohaematoanalyzer. Among various haematological parameters evaluated from acidotic goats, the mean values of Hb (12.21±0.17 vs. 10.86±0.15 g/dl), TEC (14.28±0.16 vs. 12.04±0.36 ×106/ μl), TLC (13.43±0.11 vs. 11.11±0.27 ×103/μl), PCV (36.91±0.53 vs. 29.88±0.55%), neutrophils (64.54±0.93 vs. 28.13±0.92%), MCV (23.38±0.37 vs. 19.38±1.34 fl) and MCH (7.03±0.08 vs. 6.31±0.25 pg) were found significantly increased, while the mean values of lymphocytes (28.00±0.82 vs. 65.38±0.80%) and MCHC (24.55 ±0.26 vs. 34.88±0.97 g/dl) were decreased significantly from the base values of healthy goats. It was concluded that ruminal acidosis induced due to accidental heavy ingestion of readily fermentable carbohydrate rich grains and food waste significantly altered the haematological profile concurrent with clinical manifestations in goats, and hence can be used to assess the severity of the disease.


1970 ◽  
Vol 19 (1-2) ◽  
pp. 264-267 ◽  
Author(s):  
F.H. Reuling ◽  
J.T. Schwartz

In the late 1950's and early 1960's, it became evident that some glaucoma patients developed elevations of intraocular pressure, which were difficult to control, following prolonged use of systemic or ocular medications containing corticosteroids (Chandler, 1955, Alfano, 1963; Armaly, 1963). In addition, some patients without glaucoma, when treated with steroids for long periods of time, developed clinical signs of chronic simple glaucoma (McLean, 1950; François, 1954; Covell, 1958; Linner, 1959; Goldman, 1962). Fortunately, the elevation of intraocular pressure was reversible if the drug was discontinued.Over the past decade, extensive investigation of the “steroid response” has been undertaken. For this presentation, the steroid response may be considered as a gradual elevation of intraocular pressure, occurring over several weeks, in an eye being medicated with corticosteroid drops several times a day. The elevation in pressure is usually accompanied by a reduction in the facility of aqueous outflow. When relatively large numbers of subjects were tested with topical steroids, so that a wide range of responsiveness could be observed, a variation in individual sensitivity was demonstrated. Frequency distributions of intraocular pressure or change in pressure following steroids showed a skew toward the high side. On the basis of trimodal characteristics which they observed in such frequency distributions, Becker and Hahn (1964), Becker (1965) and Armaly (1965, 1966) considered the possible existence of several genetically determined subpopulations. These investigators distinguished three subpopulations on the basis of low, intermediate, and high levels of pressure response. It was hypothesized that these levels of response characterized three phenotypes, corresponding to the three possible genotypes of an allele pair, wherein one member of the pair determined a low level of response, and the other member determined a high level of response (Armaly, 1967).


1985 ◽  
Vol 116 (1) ◽  
pp. 153-167
Author(s):  
J. W. HANRAHAN ◽  
J. E. PHILLIPS

1. Electrophysiological and tracer flux techniques were used to studyregulation of KC1 reabsorption across locust recta. Physiologically high K+levels (100 mmolI−1) on the lumen side stimulated net 36Cl flux and reduced the theoretical energy cost of anion transport under open-circuit conductions. 2. The stimulation of short-circuit current (Ibc i.e. active C− absorption) by crude corpora cardiaca extracts (CC) was not dependent on exogenous Ca2+. Stimulations of Ibc were greatly enhanced in the presence of theophylline, indicating that the rate of synthesis of cAMP is increased by CC extracts. High CC levels lowered transepithelial resistance (Rt), suggesting that chloride transport stimulating hormone (CTSH) regulates both active Cl− absorption and counter-ion (K+) permeability. 3. High mucosal osmolarity or K+ concentration decreased Ibc and caused a disproportionately large increase in Rt, consistent with a decrease in theshunt (K+) conductance. Measurements of relative mucosal-to-serosal membrane resistance confirmed that high mucosal K+ levels reduced apical membrane conductance. Lowering mucosal pH to values observed in vivo atthe end of resorptive cycles also inhibited Ibc, apparently without affecting K+ permeability.


2016 ◽  
Vol 8 (3) ◽  
pp. 1253-1259 ◽  
Author(s):  
R. A. Patel ◽  
K. B. Kapadiya ◽  
D. J. Ghodasara

The aim of the 21 day toxicity study was to evaluate the pathomorphological effect of flunixin meglumine in layer chicks. The chicks of Group I were kept as control while groups II, III and IV were fed with diet containing flunixin meglumine @ 10 ppm, 25 ppm and 50 ppm respectively for 21 days. Clinical signs viz. anorexia, dullness,lethargy, lameness and uneven growth were noticed in chicks of treatment groups III and IV only. Maximum mortality was observed in group IV (12%) followed by group III (4%). A dose dependant reduction in body weight was observed in all the treatment groups. The mean values of Kidney: Body weight ratio was significantly increased in group IV. The plasma uric acid, creatinine and BUN values were significantly increased in group III whereas increase in group IV was highly significant. Grossly, there was deposition of chalky white urates on serosal surface of kidney, heart and liver in chicks of group IV which died during experiment. Microscopically, lesions were characterized by varying degrees of congestion, haemorrhages, degeneration, necrosis and deposition of urate crystals in visceral organs of group III and group IV chicks. The intensity and distribution of pathological lesions were more severe in chicks of group IV, followed by chicks of group III. The overall lesions gave an impression that flunixin meglumine was nephrotoxic in nature.


2018 ◽  
Vol 12 (04) ◽  
pp. 279-283
Author(s):  
Julie Rambaldi ◽  
Andrea Barbarossa ◽  
Eva Morbidelli ◽  
Anna Zaghini

Introduction: Pentavalent antimony is the first choice drug for leishmaniasis in dog. Leishmaniasis has a complex pathogenesis and it manifests various clinical signs, some of which are often similar to those associated with the toxicity induced by antimonial treatment. Among the reasons for this toxicity, also a general problem of drug’s quality has been reported. Methodology: The general and local tolerability of two commercially available meglumine antimoniate based veterinary products was evaluated in 12 healthy dogs, 6 receiving Antimania (Fatro, Italy) and 6 receiving Glucantime (Merial, Spain), following repeated subcutaneous administrations of therapeutic doses for 14 days. Results: Individual and mean values of haematological and biochemical parameters in both groups remained in the physiological range, with no considerable differences within the two groups. The general tolerability of the drugs was also supported by clinical observations and physical examination of the dogs throughout the whole study period. Only slight local reactions at the injection sites, that spontaneously disappeared, were observed for both products starting from 12-84 hours after the administration. The pharmacokinetic parameters indicated no antimony accumulation. Conclusions: These results suggest that meglumine antimoniate administered at the recommended dosage regimen is well tolerated by healthy dogs, and that there is no significant difference between the two tested products.


1976 ◽  
Vol 65 (3) ◽  
pp. 669-683
Author(s):  
J. J. Nordmann

1. A study has been made of the relationship between 45Ca uptake into and hormone release from isolated rat neurohypophyses incubated in vitro. 2. Hormone secretion is triggered by high-K (56 mM) but long exposure to the stimulus does not generate a maintained release of hormone. 3. When hormone release began to wane, addition of Ba of La increased hormone output which suggests that the decline in output did not result from depletion of the neurosecretory granules at the nerve terminals. 4. 45Ca uptake is enhanced in the presence of high-K concentration, but the initial high rate declines during long exposure to the potassium stimulus with a time constant similar to that of the decline in hormone release. 5. After a period of incubation in a K-rich, calcium-free medium, addition of calcium to the medium induced hormone release. The magnitude of this release was dependent on the time of exposure to excess potassium. 6. After inactivation of secretion, mobilization of internal calcium by means of a calcium ionophore increased hormone release.


Sign in / Sign up

Export Citation Format

Share Document