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Climate change is now a global phenomenon and its impact on livelihood health and wellbeing, and overall quality of life is not deniable. No country is free from the overall impacts of climate change, but poor people of developing countries have been disproportionately affected by the adverse effects. Vulnerability in the context of climate change is a function of sensitivity, exposure and adaptive capacities. Odisha is the 9^th largest state by area and the 11th largest state by population in India. The state has an area of 155,707 km², which is 4.87 per cent of the total area of India, and a coastline of 480 km. In the eastern part of the state lies the coastal plain. It extends from the Subarnarekha river in the north to the Rushikulya river in the south. The State is broadly divided into four geographical regions, i.e. Northern Plateau, Central River Basins, Eastern Hills and Coastal Plains. The climate of the state is characterized by hot summer and cold winter in the interior parts. The state has historically been highly prone to climate change and multiple hazards – mainly cyclones, droughts and ?oods. Natural disasters devastate millions of lives and livelihoods in Odisha each year. More children and women suffer from the effects of natural disasters and this is predicted to worsen as storms ?oods and droughts become more severe and frequent because of climate change.

Introduction

According to the Intergovernmental Panel on Climate Change, climate change refers to the long-term changes (typically decades or longer) in the average state of the climate with statistically significant variations.

The climate change, defined as the long-term imbalance of customary weather conditions such as temperature, radiation, wind and rainfall characteristics of a particular region, is likely to be one of the main challenges for mankind during the present century.

A general definition of climate change is a change in the statistical properties (principally the man and spread) of the climate system when considered over long periods.

Climate Resilience

Climate resilience can be generally defined as the capacity for a socioecological system to: Absorb stresses and maintain function in the face of external stresses imposed upon it by climate change. Adapt, reorganize, and evolve into more desirable configurations that improve the sustainability of the system, leaving it better prepared for future climate change impacts.

When dealing with the evaluation of the feeds and calculating the requirements of energy and protein for ruminants, it becomes necessary to inter convert values among different systems and units. Since the accuracy of conversions/equivalents and formulae used for calculating the requirements vary with different systems/constants used, the conversion factors and formulae given here can be used only as guidelines for routine purposes in laboratory or farms in feed formulation.

Body condition scoring (BCS), although subjective in nature, is the only practical method of evaluation of body energy stores in dairy cows. The method of body condition scoring, originally proposed by Edmonson et al. (1987) and recommended by the NRC (2001) is described here. This method uses a 5 point scale, with BCS of 1 being extremely thin and a score of 5 being extremely fat. This system includes a combination of both visual appraisal and manual palpation on 8 separate body locations. Figure 1 shows the suggested BCS chart based on these locations. The assessor can score the cows using this chart with a fair accuracy, without much previous experience of scoring the cows. The scoring method is recommended for HF and Holstein crossbred cows.

Loss of BCS is expected during early lactation when a cow is mobilizing body fat in support of energy needs for lactation. Typical observed changes in BCS range from 0.5 to 1.0 condition score units during the first 60 days postpartum. A 1-unit decrease in BCS for a cow weighing 650 kg at calving (BCS 4) would provide 698 MCal of ME.That amount of ME is sufficient to support 564 kg of 4 per cent fat corrected milk.

Sampling of Milk for Analysis

A careful and accurate sampling is of utmost importance for the analysis of milk. It is a fundamental principle of sampling that the quantities withdrawn, must be proportional to the quantities contained in the respective containers and uniform throughout in its composition.Thorough mixing of milk must first be ensured either by stirring or by shaking gently. If milk from an individual animal is to be sampled, the sample should be taken from the middle of vessel containing the whole amount of milk. If the sample bottles have been standing for sometime, resulting in the separation of fat in the cream layer or lumps of fat appear, the bottles may be heated in a water bath upto 40°C to melt the fat before mixing. Milk should not be shaken very violently under any circumstance as it may result in an uneven distribution of fat.

Determination of True Protein

Apparatus

Wide mouth stoppered bottle, water bath plus those used for total nitrogen (crude protein) determination.

Reagents

1. Saturated solution of potash alum.
2. Stutzer reagent-Dissolve 40g of CuSO₄ in 2 litres of water in a wide mouth stoppered bottle. Add 10ml of glycerine and sufficient quantity of 30 % NaOH to make the solution alkaline (Litmus paper). Shake the contents and allow to settle. Discard the supernatant liquid. Collect the precipitate on a filter paper and transfer it to glass mortar with the help of spatula. Add 3ml of glycerine and a little water in the mortar and triturate the precipitate with a glass pastle. Transfer the triturated material to a wide mouth stoppered bottle, add 600ml of water, shake well and filter. Repeat the process till the precipitate (filtrate) is free from alkali and sulphate. Collect the precipitate and add 30ml glycerine. Dilute the emulsion to 320ml with water and preserve in a container.

The amount of feed or nutrient intake by an animal which is not excreted in the faeces is considered to be digested by the animals. The depiction of digested feed/nutrient as percentage of intake is known as digestibility coefficient. However, this does not represent the true value of digestibility of a feed or nutrient because during the period of recording some part of digested material is returned to the digestive tract after absorption in the body and excreted in the faeces. In addition to this some secretions of the digestive system and debris of epithelial cells are also eliminated in the faeces. These errors are quite large and highly variable for the nitrogenous constituents and minerals in the feeds. Due to these factors the determined digestibility coefficient is known as apparent digestibility coefficient. For the determination of digestion coefficient, only daily intake of feed or nutrients and faecal void values are recorded.

The availability of nitrogenous nutrients and minerals is more accurately determined by their retention (balance) in the body. Therefore, for the determination of the retention of nitrogen and minerals,metabolism trials are conducted. The routes of elimination of these constituents from the body are faeces, urine, expired air, skin secretions and milk (in case of lactating mammalian species). In a conventional balance study the loss of nutrient (s) through skin, being quantitatively little, is ignored. However, in case of some very specific study, collection of skin secretions and materials like shed hair and scurf are collected. For the collection of skin secretion (sweat) a special absorbant suit is used. In all routine balance studies, on male animals quantity of intake and void in faeces and urine are only taken into account.

Nutritional significance of tannins in feeds and fodders

Tannins are widely distributed in many types of browse plants, tree leaves, forages and feed ingredients. The structure of tannins are not completely well defined but they are polymers of phenolic and aliphatic hydroxy compounds. Although tannins and related polyphenols are considered as protein binders and, protease and cellulolytic inhibitors, they can also exert beneficial effects on rumen fermentation. There are two forms of tannins viz., hydrolysable and condensed. Hydrolysable tannins are considered to have less deleterious effects on protein digestion since these types of tannins might get hydrolysed under acidic gastric condition and release bound proteins. Attempts have been made to utilize this to advantage in protection of proteins from rumen degradation.The condensed tannins are resistant to hydrolytic degradation. The reduction in digestibility due to condensed tannins is not clear whether it is due to specific interference with cellulases or precipitation of proteins.

Certain feed ingredients have been incorporated as a source of tannins, in the diets of ruminants to benefit ruminal fermentation and performance. Inclusion of Bengal gram husk as a source of tannins in the diet of sheep prevented potentially digestible carbohydrate in the rumen, but digested post ruminally (Sreerangaraju et al., 2000).

Infra red (IR) spectroscopy is an analytical technique that serves both qualitativeandquantitativedetectionoforganicconstituents.NearInfraRed spectroscopy (NIRS) is actually a regression technique. Its predictions are based on correlations between spectral information (light absorption) and reference data fed to the spectroscopy. The principle of a NIRS machine is that a feedstuff is illuminated with light of a specific and known frequency (or wavelength) in the near infrared region. The chemical bonds in organic molecules absorb or emit infrared light when their vibrational state changes. In the near IR part of the spectrum, large changes in vibrational state are observed (overtones). In the near IR, ‘overtones’ are observed (larger than expected energy transitions that occur when molecules get ‘over excited’) resulting in broad, less well defined peaks.The characteristics of these peaks make quantification difficult as the areas of the peaks are difficult to determine and,typically,indirect (statistical) technique have to be applied to obtain usable data.Water and the C-H bonds absorb strongly in the near IR region,as do the N-H and O-H bonds,but most other have only a weak peak or none at all. The absorption of light by the feedstuff is then measured as thedifferencebetweentheamountoflightemittedbytheNIRSmachineand the amount of light reflected by the sample. Modern equipment typically uses monochromators, specially constructed mirrors that reflect light in a wavelength-dependent manner, thus allowing exposure of the sample to a single wavelength at a time. This allows samples to be scanned over the entire near IR region (they are also referred to as scanning instruments). However, as the monochromator relies on mechanical positioning of the mirror for its wavelength accuracy, the spectra generated are less reproducible from machine to machine.

Samples those are relatively transparent, such as most gases and liquids, can be assayed easily from the light transmitted (transmittance). For opaque solid samples, however, many problems arise. IR light can only travel through a few microns of opaque material. A few microns, however, can be very difficult to work with, especially when the non-homogeneous nature of most agricultural products is considered. Thus, the major challenge in applying IR spectroscopy to solid samples is sample presentation. For this technique, the sample is put into a cup and illuminated with IR light. This light can have three different fates; it can be reflected off the surface of the sample, it can enter the sample where it may be absorbed if it encounters a bond that matches the light’s frequency or, if it does not encounter such a bond, it can bounce back out of the sample. The light bounced back (or reflected) from the sample is captured and its intensity measured.

The potential of atomic absorption spectrometry/spectrophotometry/ spectroscopy for determination of metallic elements was first realized by Alan Walsh during 1950. The standard equipment termed as atomic absorption spectrometer/ spectrophotometer (AAS) has now gained a reputation in the field of analytical chemistry for determination of very small concentrations of metallic elements and metalloids. As little as 0.01 ppm of many elements can be determined through this tool. Recently, the Zeeman background correction technique has further enhanced the quality of the results obtained from the flame-less graphite furnace atomizer. Combining the very latest in AA technology with the most powerful computing and software available many manufacturers have developed several designs/models of AAS based on flame or flame-less technique.

Cotton (Gossypium) seed meal (CSM), the by-product of cotton seed oil industry, is widely used as an animal feed. However, its utilization as an animal feed is limited due to the presence of gossypol, a polyphenolie binaphthyl aldyde, which is toxic to non-ruminants such as poultry and swine and young ruminants such as calves and lambs. The gossypol (free gossypol, FG) present primarily in the pigment glands of cotton seed, is mostly converted to bound gossypol due to condensation of aldehyde group with free amino groups of proteins to form a schiff base. Formation of schiff base though results in the detoxification of gossypol to some extent, it also lowers the nutritive value by reducing the availability of lysine, the limiting amino acid of cotton seed. Thus, bound gossypol, consequently total gossypol (TG) (free plus bound) content is an important factor of cotton seed meal.

In spite of its high protein (CP, 34-36%) content, castor bean meal as such is not used as livestock feed due to the presence of toxic factors viz., ricin, ricinine and allergen. Of the three, ricin is the most detrimental to animals. In order to detoxify the castor cake, a number of physical and chemical methods are employed. The efficacy of the treatments is assessed, based on the qualitative and quantitative changes in ricin content. Of all the detoxification methods, autoclaving (15 p.s.i., 60 min) and lime (4% w/w) treatments completely destroy the toxin. (Anandan et. al., 2005).

Estimation of Ricin

The raw and detoxified samples can be analysed for the toxin, ricin as per the method of Kabat et al. (1947) with modifications as suggested by Waller and Negi (1958).

Extraction of Ricin

The solvent extracted castor cake sample of 500 g is extracted with 2.5 l of water acidified with HCl to a pH of 3.8 by shaking the contents in a conical flask for 6 h. The contents are allowed to settle and are then filtered trough Whatman filter paper No.1 . The residue is treated with 1.5 l of distilled water, shaken for 3 h and filtered through the same paper. A second treatment with water is given to the residue and filtered again through the same filterpaper.

This filtrate contains all the ricin and portions of ricinine that are soluble in cold, dilute HCI. It is evaporated to a small volume by vacuum distillation below 40 °C. The filtrate is saturated with sodium chloride and centrifuged at 4000 rpm for 20 min. to separate the precipitate containing only ricin.

Neem seed cake (NSC) despite of being rich in protein is not used as animal feed due to the presence of large number of toxic/bitter compounds in it. Studies have shown that NSC can be safely included the ration of animals after water washing / alkali/ urea treatment. These treatment methods appear to remove / reduce or largely inactivate the toxic principles present in NSC. In order to assess the quality/safety of the treated product, quantification of the residual toxic compounds is essential. One such compound is azadirachtin. It has been reported to be biologically most active.

One of the best techniques for the estimation of azadirachtin is by using high performance liquid chromatography (HPLC).

Various products of karanj (Pongamia glabra) are utilized for industrial, health and animal agricultural application in the Indian subcontinent. Despite a rich source of protein (CP 28 —34 %), karanj (honge) cake is found to be slightly bitter in taste and toxic owing to the presence of furanoflavonoid (Karanjin), restricting its safe inclusion in the livestock diets. Though a non polar solvent, soxhlet extraction of karanj seed cake with petroleum ether/ acetone drastically reduces karanjin content. The residual cake left after solvent extraction is proved to be safe as animal feed supplement.

Estimation of karanjin

The samples can be analysed for the toxin, karanjin as per the method of Prabhu et al. (2002).

Extraction of Karanjin from Raw and Processed Cake

Exactly 25 gm of ground and thoroughly mixed sample is weighed and transferred into the thimble and extracted for 12h using 200ml of freshly distilled methanol as solvent. Methanol extract is then cooled and filtered into preweighted round bottom flask using Whatman No.1 filter paper.The excess methanol is distilled off under vacuum. The flask containing the extract is weighed again to obtain the weight of extract by subtracting the empty flask’s weight. Sufficient amount of moisture free extract is transferred into vials for further analysis.

Chromatography is one of the most effective technique for accurate, fast and convenient separation and identification of the components of a mixture. The method was developed by Russian botanist Mikhail Tswett (1906), described by Karl Runge (1855). Martin and Synage (1944) received Noble Prize for developing methodology of partition Chromatography.

Partition chromatography

Partition chromatogaphy is a system comprising of two physically distinguished components - a mobile component or phase and a stationary component or phase. A mixture of substances which are to be separated is placed on the system and separation takes place on the basis of difference in distribution of molecular species in two phases. Relative movement is a result of driving force and retarding effects.

Stationary phase is the sorbent, which may be liquid or paper or gel. If it is liquid then it is held stationary by adsorbing on a solid support or matrix. The mobile phase may be solvent or developer or a gas. Since the two phases are immiscible, the partitioning is defined as the distribution of solute in two immisicible phases which are in contact with one another. When a column is filled with the sorbent and solvent the two phases form a large number of theoretical plates. Each plate contains both the phases. Solutes in solution (mixture of substances to be separated) is layered on the top of the column and when it enters to the column it distributes in the two phases. The ratio of the concentration of a solute in two phases is called its partition coefficient. The resolution of solutes improves as the length of stationary phase increases.

Nutrition plays a pivotal role for the animal research, be it health or production. Research in animal nutrition employs many basic techniques and chromatography is one of them. Chromatographic processes can be defined as separation techniques involving mass transfer between stationary and mobile phases. Various types of chromatography have one application or the other in analysis of food/feed components (Day and Williamson, 2001), quantitation of nutrients as well as the characterization of the effect of nutrients in biological samples like serum/plasma or tissues (Merken and Beecher, 2000).

A. Principle

Basically all chromatographic systems consist of the stationary phase that may be solid,gel,liquid or a solid/liquid mixture that is immobilized and the mobile phase, which may be gas or liquid and it flows over or through the stationary phase. This partition is achieved in one of the following ways:

Adsorption chromatography : It is one of the oldest types of chromatography. It utilizes a mobile liquid or a gaseous phase that is adsorbed onto the surface of a stationary solid phase. The equilibrium between the mobile and the stationary phase accounts the separation of different solutes e.g. adsorption chromatography, hydrophobic interaction chromatography.

Partition chromatography : It is based on a thin film formed on the surface of a solid support by a liquid stationary phase. Solutes equilibrate between the mobile and the stationary liquid (e.g. partition chromatography, reverse phase chromatography, gas-liquid chromatography, etc.).

Principle

Polyethylene glycol (PEG) is a high molecular weight compound which is inert to rumen fermentation. The concentration in the rumen liquor declines with the passage of digesta from rumen to lower G.I. tract and is proportional to time. Protein free filtrate of rumen liquor gives turbidity in the presence of trichloro acetic acid and barium chloride which is a measure of PEG concentration at different post feeding hours.

Principle

Nucleic acids leaving the rumen are mainly of microbial origin which are extensively digested in the small intestine and the purines liberated are absorbed. Only a small amount of absorbed purines are utilized by the host animal, the rest are metabolised forming hypoxanthine, xanthine, uric acid and allantoin. These metabolites are excreted mainly through urine. Therefore, with the understanding of how urinary excretion of purine derivatives (PD) respond to purine absorption i.e. the response curve of PD excretion to purine input into intestines, the microbial purine outflow from the rumen and the microbial N supply to the ruminant animal can be estimated by measuring the purine derivatives excretion through urine.

Introduction

In ruminants,nutritional studies are very complicated unlike non ruminants where it is quite simple. In non-ruminants, analysis of feed taken and faeces voided by the animal gives overall picture of digestion and nutrient availability to the animal. In ruminants, since it has a complex microbial digestive system (rumen) within the animal digestive system, the analysis of the feed taken and faeces voided will not express the whole processes in the GI tract of the animal. To have complete picture, it is necessary to study at the site of microbial digestion (rumen). For such study, samples from the rumen have to be drawn and analyzed for metabolities, microbial enzymes etc.

6.1 Kinetics of Rumen Digestion

The rate and extent of digestion of dry matter or organic matter in the rumen is regarded as the important parameter to predict voluntary feed intake (Khazaal et al., 1993; Blummel,1994). Voluntary feed intake is responsible for more than 50 per cent of the variations in animal response to the diet (Van Soest, 1994) and with low quality unsupplemented roughages, this can be as much as 93% (Blumme1,1994). Therefore, any parameter of feed evaluation that would indicate the voluntary feed intake would be a useful parameter to judge the quality of feedstuff. The rate of digestion of any feed component can be measured by determining extent of digestion at intervals of time. Therefore, the techniques for determining extent of digestion, such as the rumen in vitro techniques (Tilley and Terry, 1963; Goering and Van Soest, 1970) or the in situ Dacron bag technique have been adopted to derive rate of degradation of dry matter of any particular component of the feedstuff. However, unlike in determining the extent of digestion, wherein the incubation is turned off at one particular time (normally 48 hours), measurement of rate of digestion, requires termination of incubation at several points between the start of incubation and until at least 90% of the potentially digestible dry matter is digested (72 or 96 hours). This generates a large number of samples for analysis.

In gas production technique, since gas produced from digestion of substrate is accumulated in the incubations, measurement of gas at different times of incubation would reflect the extent of digestion at different times of incubation. Therefore, unlike with other in vitro / in situ techniques wherein, digestion is determined from the gravimetric disappearance of feed at different times of incubation, gas production technique offers the possibility of using cumulative gas production at different times of incubation to measure the rate of digestion. Thus, a single incubation of feedstuffs is adequate to measure the rate of gas production.