eChapters

Introduction

The phytohormone abascisic acid (ABA) was discovered in connection to studies related to shedding of fruits and leaves, also called abscission, and the dormancy of buds. It was first identified and characterized by Frederick Addicott and his associates in 1963 while studying the compounds responsible for the abscission of cotton fruits. Inhibition of growth and maintenance of the dormancy of buds are the most important visible effects of ABA. The concentration of ABA does not remain constant as its concentration decreases in the buds significantly after sprouting and rises during seed and fruit production. Its concentration in dormant seeds is very high and considered as an efficient inhibitor of germination. The role ABA plays during the abscission of fruits and leaves is not clearly understood as its effect is very clear in case of fruit abscission where as it is not very clear on the abscission of leaves. However, the regulatory effect of ABA on the water balance is established in plants. It also induces stomatal closure to inhibit further loss of water. Being a growth inhibitor, ABA also reverses the effect of growth-stimulating hormones like auxin, gibberellins and cytokinin in different tissues of a plant. One of the main goals of phytohormonal ecology is to study the interactions between biotic and abiotic stress at hierarchical levels of biological organization.

9.1 Potential Tracer Difficulties and their Corrections

In radioactive measurements, the observed counting rate is not equal to the true disintegrations rate of the sample since a number of factors like nature of detectors tend to increase it or, in a majority of cases, decrease the actual counts. Some of the important factors responsible for this are

1.Background,

2.Backscattering

3.Absorption

4.Self absorption

6.Geometry

7.Instrument efficiency

One of the major constraints in the efforts to modernize and efficient restructuring of the animal husbandry practices is the delay in taking the results of research to the farming community and in persuading them to adopt new, profitable and locally relevant technologies. The very need of the extension work is to bridge the gap between what is known to the scientists in the laboratories and what is actually being practiced by the farmers in the field. In other words, the major goal of extension machinery is to accelerate the processes of communication and to motivate rural people or livestock owners for adoption of new and profitable technologies. Hence, it is very important to understand these processes of how the farmers get such technologies and how they adopt them.

Communication

The term communication is originated from the Latin word ‘Communis’, meaning common or establishing commoness. When we communicate, we attempt to establish ‘commonality’ with someone through the message.

Communication is the process by which two or more people exchange ideas, facts, feelings or impressions in ways that each gains a common understanding of the meaning, intent and use of the message (Paul Leagens, 1961).

Diffusion and Adoption of Livestock Innovations

One of the important functions of livestock extension worker is communication. This communication is not mearly informing the livestock owners about the improved technologies and practices, but to ensure the application of technologies for their benefits. Livestock extension worker’s efficency are always judged and measured (a) by the speed or quickness with which the gap between what is known and what is done by the livestock farmers is bridged, (b) by the number of new practices adopted; and (c) also by the number of livestock farmers and communities that adopt the new practices. While discharging the technology dissemination function, livestock extension worker often faces with some of the difficult questions:

The diffusion and adoption process represents a fundamental mechanism through which innovations, practices, and ideas spread through communities and social systems, making it essential for understanding how community mobilization initiatives can expand their reach and impact while building sustainable social change that extends beyond initial implementation sites. This process encompasses the complex social, psychological, and institutional factors that influence how individuals and communities learn about new approaches, evaluate their potential benefits and risks, and ultimately decide whether to adopt and integrate these innovations into their existing practices and belief systems. Understanding diffusion and adoption processes provides community mobilization practitioners with crucial insights into how successful interventions can be scaled up and replicated across different contexts while identifying the factors that facilitate or hinder

5.1. Diffusion

Process by which an innovation is communicated through certain channels over time among the members of a social system.

Introduction

Diffusion is the process by which an innovation is transmitted to the members of a social system over some time and through channels in a specified manner. According to Rogers (1962), this is a unique form of communication in which the messages are focused on innovative concepts. The concepts can include (i) A new idea, (ii) An idea that is communicated via certain channels (iii) Among the members of a social system (iv) Overtime. On the other hand, the adoption process is the mental process through which an individual passes from first hearing about an innovation to final adoption, as defined by Rogers (1962).

Diffusion

Diffusion is the process by which an innovation is communicated through certain channels over time among the members of a social system (Rogers & Shoemaker, 1971).

Innovation

Innovation is an idea, practice or object that is perceived as new by an individual or otherunit of adoption.

Adoption

Adoption is a decision to make full use of an innovation as the best course of action available.

Introduction

Agriculture plays important role in boosting economic activity of farmers. Since it transfers new technologies within the knowledge and information system, it has special features related to knowledge, innovation, and those three. Agribusiness farming needs the diffusion of innovation. Many farmers were unable to boost their earnings. The development of the agribusiness and the welfare of the farmer were both significantly influenced by innovation. Diffusion includes three fairly distinct processes i.e. presentation of the new culture element or elements to the society, acceptance by the society, and the integration of the accepted element or elements into the pre-existing culture (Linton, 1936).

Thousands andthousands ofsamples ofvarious feeds andfoddersweresubjected to Weende analysis fortheir chemical composition have been depictedin various manuals. Such proximate principles of these feeds provide only the potential value forreference or consultationpurpose, but not theactualvalue of feedstuffs. Losses of nutrientsinfaeces(solids), urine (liquid), gasesetc.duringthe digestion, absorption andmetabolismof theanimal shouldalso be taken into consideration. Therefore, a need arises to conduct digestibilitytrial or experiment for the feeds in the ruminant animals. Major portion of the nutrients present in the feeds are not properly digested in the gastrointestinal tract (G.I.T.), hence not completely available to the animal body. Digestibility is that portion of a feed or any single nutrient of feed, which is not excreted in the faeces or dung and it is therefore, assumed to be absorbed by the animal. When this digestibility is expressed in percentage, it is termed as ‘digestibility coefficient (D.C.)’.

Body needs energy for the functioning of various processes for the nutrition and repair of damage tissue. This energy comes from the food nutrients. The food nutrients undergo a series of chemical reactions in the body to release the necessary energy.

The higher animals are dependent on plants and other animals for their nutrients. They can classified into two groups.

Carnivores : Those animals which obtain most of their food by eating other animals are carnivores in these species digestion is mainly enzymatic in nature and microbial digestion is minimal.

Herbivores : These animals obtain most of their food nutrients from herbage and other plant parts. In the herbivores, microbial digestion is of great significance and allows utilization of plant materials that are not broken down by the enzymes present in the digestive secretions.

Most of the domesticated animals except cat & dog fall in the category of herbivores. The domesticated herbivores can be divided into three groups:

1. Ruminants : Those possessing a rumen (cow, buffalo, sheep, goat, camel etc.) in which there is extensive microbial fermentation of the herbage diet in a specialized region of the digestive tract, prior to its digestion by the alimentary enzymes.
2. Psedoruminants eg members of the camelidae family eg camel, Ilama, alpaca, vicuna etc. In pseudoruminants animal third compartment of the compound stomach is absent.
3. Non-Ruminant : The second group is those with simple stomachs (Horse, Pig) in which fermentation takes place in the posterior part of the digestive tract.

Introduction

Digestion may be defined as the hydrolytic process carried out by various enzymes for breaking down complex food components such as proteins, fats and carbohydrates into simpler molecules like amino acids, fatty acids and monosaccharides, respectively. Whereas, absorption may be defined as the movement ofthese simple soluble digested food componentsalongwithvitamins, minerals and water from gastrointestinal track into the circulatory system.

The process of digestion starts from oral cavity (mouth) and ends at large intestineincluding tongue, teeth, jaws,secretions from salivaryglands (parotids, sub maxillary or submandibular and sublingual glands), pharynx, esophagus, stomach, small intestine and digestive enzymes secreted from pancreas and liver.

The history of digestion experiments dates back to the mid-19th century when the first true trials were carried out at the Weende Experiment Station in Germany. In 1858, researchers Henneberg and Stohmann began their experiments and published their findings in 1860, which condemned Thaer’s hay equivalents and gave results of their experiments. These trials coincided with the chemical analysis of feedstuffs at the Weende station. Even before 1860, studies on nutrient losses in feces had been conducted to calculate TDN (total digestible nutrients). Over time, numerous publications have recorded the results of digestion experiments, with Schneider and Flatt (1975) documenting more than 3000 studies. In India, over 430 digestion trials have been conducted with Indian feeds and fodders at various research stations, as published by ICAR. The wealth of information gathered from these experiments has greatly advanced our understanding of digestion processes and has enabled improvements in animal nutrition practices.
Digestibility
Nutrients in feed are not fully utilized by livestock, with a significant portion being excreted in feces due to incomplete digestion in the digestive tract. Digestibility can be defined as the proportion of nutrients that are absorbed by the animal’s body and not excreted. It is essential for the animal’s growth, reproduction, and overall metabolism. Animals fed highly digestible feed show improved growth and reproductive performance, leading to increased market availability.
The formula for calculating digestibility is simply the difference between nutrients in the nutrient consumed and nutrients found in faeces.
Digestibility = Nutrients in forage – Nutrient in faeces

Reagents

Nuclease-Free Water: 14µl

10X Restriction Buffer: 2µl

Acetylated BSA (1mg/ml): 2µl

DNA (~1µg): 1µl

Restriction Enzyme (10u): 1µl

Final Volume: 20µl

Mixture of nutrientscomprisingcarbohydrates, fats, proteins, minerals, vitamins and water are feed stuffs. From the intestinal wall, very few of such nutrients can pass directly to the body tissues, therefore they must be degraded down into simple compounds before they pass through the mucous membrane of the gastrointestinal tract (G.I.T.) intothe bloodand lymph. This degradation process is regarded as ‘digestion’. Thereafter, the movement of these simple compounds through the mucous membrane oftheG.I.Tract into the blood iscalled absorption. Metabolism is the utilization of these nutrients by the animal body and then excretion of the end products takes place from the body. The digestion of feeds is carried out by three means namely, mechanical action: mastication in the mouth and the muscular contraction of G.I.Tract; chemical action: this is carried out by enzymes secreted by digestive juices and microbial action: this is also enzymatic action, but the enzymes are secreted by microbes instead of host.

In ruminants, it is the rumen which harbours bacteria, protozoa and fungi (Fig. 1) ; whereas in non-ruminants, it is the large intestine (Fig. 2). There are four compartments in the stomach-reticulum, omasum, rumenand abomasums. Reticulumprovides ruminantadditionalspacefor storage.Also, if byanychance, foreign bodies like nails, wires etc. reach over here alongwith feed, they are retained for longer periods and thus, soft organs are protected. Omasum squeezes out water from the feed with the help of its strong muscular walls. In the suckling calves or lambs, the two compartments-rumen and its continuation reticulum are less developed and both are joined by a tube like structure -oesophageal or reticular groove, which directly opens into abomasum. That is why in these sucklings, milk reaches straight into the abomasum, which is the true stomach. Rumen develops at about six weeks of age in these young ones. As these sucklings begin to eat solid feed, both rumen and reticulum enlarge greatly and separate. Now oesophageal or reticular groove does not exist.

Stomach

The stomach of ruminants (Fig. 4-4 A) is compound stomach with four parts; the rumen, reticulum, omasum and abomasum. The first three compartments comprise the forestomach or proventriculus. These parts have a nonglandular mucous membrane lined by a stratified squamous epithelium and are concerned with maceration, fermentation and cellulose digestion while the last part, the abomasum has a glandular mucous membrane which is concerned with digestion of the food material with the help of gastric juices. The relative sizes of the four compartments change with the age of the animal. In new bourn calf the rumen and reticulum together have about half the capacity of abomasum. But, as the diet of the animal is restricted to milk during this period, these two compartments remain collapsed and functionless. At eight weeks of age, the total capacity of rumen and reticulum equals to that of the abomasum and at twelve weeks of age the combined capacity of rumen and reticulum doubles to that of the abomasum. During this period the growth of the omasum is slow and steady. At about one and half years of age the omasum and abomasum equals in their capacity. At this age the four parts reach to their definitive size, shape and capacity. The relative capacity of the four compartments at this stage is rumen eighty per cent, reticulum five per cent, omasum seven per cent and abomasum eight per cent. The total capacity of average sized cattle varies between hundred fifteen to hundred fifty litre.

18.1 Introduction

The digestive system of fish shows remarkable diversity in its morphology and function, related to both taxonomy and different feeding habits (Abdulhadi, 2005). Fish eat a wide variety of foods. Some feed on plants, others on small fish, and the remainder are omnivorous. The digestive system is drastically altered as a result of different feeding habits. In response to feeding habits, the structural plan of the buccal cavity, pharynx, and rest of the gut has changed.

The digestive system of insects comprises of two main sub-parts, one is the alimentary tract or also known as the digestive tract and the associated digestive glands. These digestive glands may be associated directly or indirectly such as, salivary glands, gastric, caeca (directly) and Malpighian tubules (indirect). If we have to describe an insect and its anatomy, or its histology, it is based on the orthopteroid plan, which is mostly shown by grasshoppers, crickets, and locusts, because their plan shows and describes the basic, primitive design from which other groups of insects have enolved and showed modifications and specialization. We can say that this orthoptera insect shows the general anatomical and histological features of a generalised insect.Today, we see that insects have invaded and adapted in almost all types of habitats and the major reason for their biological success is their ability to show digestion, utilization and their ability to eat an extremely vast diversity of food. It is due to this abilityof extremizm in food diversity that insects have undergone many specializations and modifications of the alimentary canal. What modifications a species of insects undergoes, depends upon the type of insects, depends upon the type of food it consumes. The diversity is also seen in the way of obtaining, storing, processing and absorbing the food. These differences may be structural or functional or both. It is not necessary that these differences must be present in different species only, those may be shown by different life stages of a single insect, by two sexes of a single species, etc. e.g., the difference between the mouths parts of mosquito species.