Nitrogen and phosphorus nutrition of cattle: reducing the environmental impact of cattle operations.

Brassica napus L. is a vegetable oil crop, commonly known as rapeseed (or canola). It is widely used as a source of oil and protein for food and industrial applications, but also as a remedy, and in a field of attraction or as an ornament due to its diverse flower colors. Every part of rapeseed is useful, even the waste, which could be used to feed animals, or recycled. In this review, the use of rapeseed in these applications is presented, starting with the preparation of oil and protein from the seeds, before their release in the market, to the utilization of natural unprocessed rapeseed. Progress in rapeseed exploitation for food, remedy, energy source, and industrial applications are analyzed to show variability in diverse findings, to provide insights and progressive descriptions of rapeseed usage to other scholars. Moreover, advancements in breeding for rapeseed improvement were described. In the future, strategies could be developed or improved to avoid or decrease crop losses, but also to increase interest in propagating the valuable traits of rapeseed.

Rapeseed (Brassica napus): Processing, Utilization, and Genetic Improvement

Mammalian hair growth is reduced by applying to the skin a composition including an inhibitor of 5-lipoxygenase.

Inhibition of hair growth

The effect of nutrient status on the growth and properties of wool and mohair fibers is reviewed: the aim is to compare effects on sheep and Angora goats and emphasize differences between the species. Wool growth is markedly influenced by nutrition; the requirement for energy-yielding nutrients is low and the major nutrients limiting wool growth are essential AA, sulfur-containing AA being especially important. An adequate supply of Cu, Zn, folic acid, and pyridoxine is required to maintain wool growth. Both length growth (L) and diameter (D) of wool fibers respond to changes in nutrient supply such that the ratio of L:D remains approximately constant. Mohair production is influenced by nutrient supply. However, the importance of specific nutrients has not been established, apart from one study showing that mohair growth responded to parenteral supplementation with methionine. In contrast to sheep, some studies indicate that length growth of mohair fibers may not be very responsive to changes in nutrient status. The responsiveness of mohair growth (both length and diameter) to nutrient supply at different times of the year has not been reported. The energy requirement for fiber growth may be greater in goats than in sheep, but more studies are needed.

The nutritional control of the growth and properties of mohair and wool fibers: a comparative review.

The mammalian hard α-keratins constitute a homologous group of epidermal appendages comprising wool, hair, hoof, the horns of cattle, goats, sheep, and rhinoceros, claw, baleen, and the quills of porcupine, echidna, and hedgehog Although of common embryological origin and sharing a common structure, they cover a very large range in amino acid compositions Some examples are given in Table I where it can be seen that there is a large variation in the proportion of nearly every amino acid This precludes a simple compositional definition for hard α-keratins and instead requires a detailed list of chemical and structural characteristics, which can be summarized as follows: 

1

Epidermal appendages, usually cystine-rich, which are insoluble in usual protein solvents except at extremes of pH, due primarily to an extensive network of disulfide bonding




2

After solubilization following fission of disulfide bonds, hard α-keratins yield two or three characteristic and unique families of constituent proteins, named because of peculiarities in composition, low-sulfur, high-sulfur, and high-tyrosine proteins




3

X-ray diffraction analysis and electron microscopy show that these tissues have a unique arrangement of the constituent proteins, comprising intermediate filaments (IFs) traditionally termed microfibrils, usually aligned in the growth direction, surrounded by a nonfilamentous matrix of IF-associated protein (IFAP)

The Proteins of Hair and Other Hard α-Keratins

Merino sheep were given abomasal infusions of various amino acids or mixtures of amino acids. Effects on wool growth were measured using autoradiography or a clipping procedure and changes in the concentration of amino acids in plasma were measured in some experiments.Mixtures of five (28 g/day) or ten (45 g/day) essential amino acids (both mixtures containing 3 g methionine) stimulated wool growth of sheep receiving a maintenance ration; on average, the volume of wool grown increased 48% and 86%, respectively. When cysteine completely replaced methionine in these mixtures, wool growth was markedly reduced, but two-thirds of the methionine could be replaced by cysteine without affecting wool growth. Homocysteine was partially effective in replacing methionine and, when supplemented with betaine, folic acid and vitamin B12, the mixture was still significantly inferior to that containing methionine. In contrast, abomasal supplements of methionine or homocysteine alone were equivalent as supplements for wool growth. The results indicated a specific role for methionine in the control of wool growth, other than the provision of cysteine. This role was postulated to be related to some function of S-adenosylmethionine.Infusion often essential amino acids caused appreciable increases in the concentrations of cystine, methionine, cystathionine and taurine in plasma; total essential amino acids increased threefold whereas nonessential amino acids decreased in concentration. The replacement of methionine in the infusion by cysteine or homocysteine significantly altered the concentration of cystine, methionine and cystathionine in plasma.Evidence was obtained that the adverse effects on wool growth of high abomasal doses of methionine (10g/day) could not be reduced or prevented by provision of additional glycine and were not related to the supposed toxic effects of 3-methylthiopropionic acid, a metabolite of the transamination pathway.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0021859600071008

Effects of the infusion of amino acids into the abomasum of sheep, with emphasis on the relative value of methionine, cysteine and homocysteine for wool growth.

The relative importance for wool growth of energy-yielding nutrients compared with amino acids required for incorporation into wool proteins was assessed in an experiment in which most nutrients were supplied via the abomasum. Nine nutritional treatments, providing three levels of protein (53, 99 and 145 g/day) to the intestines at three levels of energy (5.2, 7.5 and 9.7 MJ/day), were given to 12 Merino sheep during three consecutive periods of 3 weeks in a balanced lattice design. Abomasal nutrients consisted of varying proportions of casein, whole milk, glucose and glycerol. There was a large effect of protein supply on all components of wool growth, but there was no significant effect of energy. There was a significant interaction between the effects of protein and energy supply on diameter, length growth rate and volume of wool, but it was small relative to the main effect of protein. Extra energy appeared to enhance wool growth at the highest level of protein but reduce it at the lowest level of protein. The concentration of urea, cystine, methionine and other essential amino acids in plasma increased with protein level. Increasing energy supply reduced the concentration of urea and essential amino acids in plasma but not that of cystine or methionine. The experiment confirmed the major role of amino acid supply in controlling wool growth but indicated that there may be a small interaction with energy supply.

Effects of Abomasal Protein and Energy Supply on Wool Growth in Merino Sheep

Sheep were given intravenous infusions of ethionine together with cycloleucine or reduced glutathione, in attempts to prevent the inhibition of wool growth by ethionine. Other sheep were given cycloleucine alone to measure effects on wool growth. Twenty-two compounds related to cystine, methionine, ethionine, lysine, phenylalanine and tyrosine were given as intravenous infusions to sheep to investigate their potential as depilatory agents. Nineteen of these compounds were also tested in mice during their first cycle of hair growth. The concurrent administration of cycloleucine with ethionine prevented the weakening of wool fibres caused by ethionine, but reduced glutathione was ineffective. Cycloleucine weakened wool fibres, as judged subjectively, and caused a small reduction in fibre diameter. Selenocystine and selenomethionine caused some hair loss in mice but selenocystine was also toxic. Both seleno-amino acids were toxic for sheep; selenocystine was lethal at 0.025 mmol kg-0.75 and selenomethionine at 0.09 mmol kg-0.75. Doses that permitted survival of sheep did not have depilatory effects. However, the presence of autophagic vacuoles in the cytoplasm of follicle bulb cells of sheep indicated that a toxic dose of selenocystine had potential depilatory activity. Other compounds investigated did not induce loss of wool or hair. Some compounds, notably 3-methylthiopropionic acid and S-(2-aminoethyl)-L-cysteine, were toxic to mice but not sheep. The methionine analogue, methoxinine (O-methyl-DL-homoserine), caused a substantial reduction in the strength of wool fibres and a prolonged alteration of the crimp pattern. It is suggested tentatively that cycloleucine inhibits methionine adenosyltransferase and thereby reduces or prevents the formation of S-adenosylethionine. The failure of various compounds related to methionine and ethionine to have any depilatory activity in sheep supports the view that ethionine influences wool growth via the formation of S-adenosylethionine.

/pdf/investigation-of-some-amino-acid-analogues-and-metabolites-5gu30pmw0r.pdf

Investigation of some amino acid analogues and metabolites as inhibitors of wool and hair growth.

Summary The chemicals were administered, subcutaneously, orally or topically. Generally, the depilation produced in the mice by mimosine or cyclophosphamide differed from that produced by the steroid analogues tested. In the first 2 cases almost completely naked mice were commonly seen, while in the steroid-treated groups the complete inhibition of all hair fibres was rare. This is discussed in relation to the effects of the same compounds on wool growth in sheep. When related to body weight, the doses of cyclophosphamide (62 mg/kgO.15) and dexamethasone (5-10 mg/kgO.7'), that depilated mice in our experiments were in good agreement with those reported to inhibit the growth of wool fibres in some sheep. An example of synergism in depilatory effect between dexamethasone and cyclophosphamide is also presented. The time of onset and the initial spread over the body of the 2nd hair cycle in depilated mice was observed. We are investigating chemicals that interrupt wool fibre growth in sheep, including mimosine (Reis, Tunks & Chapman, 1975) analogues of mimosine (Ward & Harris, 1976), adrenocortical steroid analogues (Panaretto & Wallace, 1978a, b), and alkylating agents such as cyclophosphamide (Reynolds, Dolnick, Sidwell & Terrill, 1972). A quick assessment of any inhibitory effects on hair growth is often wanted. Newly-synthesized analogues of molecules known to inhibit hair fibre growth are often produced in quantities too small for testing in large animals such as sheep, and a preliminary test is required to determine whether larger quantities should be made for further investigation. Another requirement is to determine whether 2 inhibitory substances can act synergistically. The tissue-culture system for screening depilatory agents (Ward & Harris, 1976) fulfils some of these requirements but could not be used, for example, for testing glucocorticoid hormones, which were inactive during the 4 h of their tests. The test system described here provided information not available from the in vitro system, for example, about toxicity or untoward side effects.

Depilatory effects of certain chemicals during the first hair growth cycle in sucking mice

As part of investigations into the pattern of cell division and differentiation in the wool follicle bulb, the thymidine analogue 5-bromo-2'-deoxyuridine was used to label cells in S phase. A mixture of 5-bromo-2deoxyuridine and 5-fluoro-2'-deoxyuridine was injected into sheep held at a constant plane of nutrition. fibre length growth rates were measured by injecting the animals with either 35S-labelled methionine or cysteine, followed by autoradiography of individual fibres. Fibres from 5-bromo-2'-deoxyuridine/5-fluoro-2'-deoxyuridine treated animals exhibited both abnormal cuticle scale patterns and disorganized ortho- and paracortex as determined by staining with methylene blue. Orthocortex differentiation in wool follicle bulb keratogenous zones was visualized using a monoclonal antibody specific for orthocortical cells (HiT 96). We determined that the normal pattern of orthocortical cell differentiation was reversibly inhibited by 5-bromo-2'-deoxyuridine/5-fluoro-2'-deoxyuridine treatment. Fibre length growth rate was reversibly decreased very slightly as a result of 5-bromo-2'-deoxyuridine/5-fluoro- 2'-deoxyuridine administration. We conclude that 5-bromo-2'-deoxyuridine/5-fluoro-2'-deoxyuridine can grossly perturb aspects of wool follicle bulb cell differentiation without profoundly affecting fibre length growth rate. Although 5-bromo-2'-deoxyuridine/5-fluoro-2~-deoxyuridine labelling is an inexpensive, nonradioactive method of visualizing S phase nuclei, the possibility of artefacts resulting from such treatment should be borne in mind.

Perturbation of Wool Fibre Cell Differentiation by a Mixture of Bromodeoxyuridine and Fluorodeoxyuridine

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