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Effects of Heat Stress on Milk Production in Cattle

by Yadav Sharma Bajagai


Reduction in milk production is one of the major economic impacts of climatic stress in dairy cattle. Decrease in milk yield due to heat stress is more prominent in Holstein than in Jersey cattle [1]. Decreased synthesis of hepatic glucose and lower non esterified fatty acid (NEFA) level in blood during heat stress [2, 3, 4] causes reduced glucose supply to the mammary glands resulting low lactose synthesis which in turn ensues low milk yield [5]. Reduction in milk yield is further intensified by decrease in feed consumption by the animals to compensate high environmental temperature [5, 6].

Role of Methane in Global Warming



Although the proportion of CH4 in the atmosphere is very low compared to CO2, the relative contribution of CH4 to global warming is high due to the high radiative forcing contributed by this gas. The global atmospheric concentration of methane reached 1774 ppb in 2005 compared to 1732 ppb in the early 1990s and only 715 ppb in the pre-industrial era (figure). This increase in atmospheric concentration of CH4 is responsible for radiative forcing of +0.48 ± 0.05 W m–2 which is second only to that contributed by CO2 due to CH4 having approximately 25 times higher global warming potential (GWP)  compared to CO2. Therefore, reduction in CH4 emission is more effective and probably an easier strategy than reducing CO2 emission.

Figure: Trend in the increase in atmospheric concentration of CH4 over the last 10,000 years and since 1750 (inset) with corresponding radiative forcing. Source: IPPC (2007)

P.S. References available on request.

Major issues about the Safety of Meat in Nepal

by Yadav Sharma Bajagai


Safety of meat sold and consumed in Nepal is a major concern since long and debate about the legislation and its enforcement to assure safe meat to public has been continuing for more than a decade. Recent incidence about import of frozen chicken by International food chain Kentucky Fried Chicken (KFC) from India once again makes meat safety the issue of widespread public and media interest. Government has suspended the suspected officials and started the investigation. This is out of scope for this article but issues about meat safety and enforcement of legislation has been discussed here. 

Role of Ruminant Animals in Global Climate Change



Ruminant animals are great contributors to the human food chain due to their ability to utilize complex polysaccharides in plant cell walls (cellulose, hemicelluloses and pectin), which are otherwise non digestible to any of the mammalian digestive enzyme and turn these into meat and milk for human consumption. Digestion of these polysaccharides in ruminant diets is attributable to anaerobic biodegradation of these compounds into their respective monomers by microorganisms (bacteria and fungi) present in the forestomach of the animals. In spite of their contribution to the human food chain, ruminant animals are often debated as one of the contributing factors in global climate change due to the emission of CH4 as a byproduct of fermentative digestion of feedstuffs in the forestomach. In addition, production of methane by ruminants causes a significant amount of feed energy loss which could be used for animal growth and production if methane production is prevented.

International Debate on Climate Change: Developed Countries Vs Developing Countries

by Yadav Sharma Bajagai


In 2009, the United Nations climate change conference was held in Copenhagen, Denmark. There was a widespread hope to the world community about the conference that it would bring a significant policy and commitment to reduce the emission of greenhouse gases. But, the conference couldn’t make a consensus decision and thus the accord of the conference was not passed unanimously. The seeds of the debate seem to be sown in Kyoto protocol in which principle of “common but differentiated responsibilities” has been initiated. According to this principle developed and industrialised countries which led the industrial revolution are responsible for most of the greenhouse gases now in the atmosphere and therefore should bear a greater responsibility for combating climate change. As a consequence of this principle in Kyoto protocol some large developing nations such as China and India were exempted from the same emissions-reductions obligations as developed countries. Developing countries want rich countries to take bold action to cut their greenhouse emission but developed countries like USA are seemed to be reluctant as it would affect their economy. Furthermore, the developed nations want the same level of commitment and action from high emitting developing nations like China and India but the developing nations led by China and India still oppose taking on mandatory obligations to reduce their emissions. This debate of ‘who is responsible and who should take action’ distracting the world leader from the real problem. 

Management of Heat Stress in Horse

by Yadav Sharma Bajagai

Any physiological, metabolic, behavioral and performance abnormality in animals due to inability of thermoregulatory mechanism to regulate normal body temperature during high ambient temperature can be referred to as heat stress. Heat stress is not only the concern of only tropical region but also a matter of major apprehension in sub-tropical and temperate regions too as frequent spells of high ambient temperature and gradual rise in global atmospheric temperature is being experienced in many of the temperate regions of the world due to global climate change.

Heat stress is one of the greatest climatic challenges faced by horses affecting animal health and welfare in the area of the world where ambient temperature often exceeds upper critical temperature. 

Principle of management of heat stress during hot weather is to hasten the heat loss and avoid the heat gain as far as possible.

Socioeconomic factors affecting the scenario of the first influenza (swine flu) pandemic of 21st century

by Yadav Sharma Bajagai

During March-April 2009, a new episode of highly contagious respiratory infection (influenza) was emerged from Mexico which was found to be caused by a novel strain of the influenza virus H1N1 believed to be originated from swine and thus widely called as swine flu. The disease soon spread widely across many countries through human to human transmission and World Health Organization (WHO) declared that as first influenza pandemic of 21st century with pandemic alert phase 6 on 11 June 2009. The disease has been declared to move into post-pandemic phase on 10 August 2010. It was estimated that more than 200 million people were affected worldwide from this pandemic influenza causing death of more than 17000 people . Children, young adults and pregnant women were particularly susceptible to the disease.

After its first appearance in Mexico and California during March and early April 2009, the influenza was reported by 208 countries till the end of 2009. The number of countries increased to 214 till April 2010. Although the spread of disease was more gradual in Northern hemisphere spreading from USA to Spain, England, Japan and Germany, the disease spread quickly in Southern hemisphere affecting most of the countries. The countries affected by the disease and death of people due to the pandemic are depicted in figure 1.

 

Figure 1: Countries affected by 2009 pandemic influenza and cumulative death of the people. Source: WHO.


Aid Dependency in Africa: An Example of 'Shifting the Burden' System Archetype

by Yadav Sharma Bajagai


Development aid or assistance is the major financial source in developing countries after rich countries made an agreement in 1970 to donate 0.7% of their gross national income annually as official international development assistance. However, it is widely criticized that these development aids have more negative impacts than benefits in overall socioeconomic developments of poorer nations. The development aid in Africa and its long term impact has been described here as an example of ‘shifting the burden’ system archetype. 

Figure: Causal Loop Diagram of Aid dependency in African Nations