Science communication for non-scientific audiences in food security (agriculture, animal science, veterinary science, food policy, food safety and related field), environment (climate change, sustainability, natural resource management and related field), sustainable development and system thinking.
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Impacts of climate change on Pig
by Yadav Sharma Bajagai
are particularly susceptible to increased environmental temperature because evaporative cooling by sweating is of limited value to
them due to barely functional sweat glands. Impacts of thermal stress
on pig due to increased ambient temperature are described here briefly.
has been shown that pigs under thermal stress consume more feed during cool
hours of the day (morning) than during hot hours (afternoon) and drink more
water during hot hours (afternoon) than during cool hours (figure 1 and 2) . Overall
consumption of feed is lower in the area of high temperature than in area of
thermal comfort  and water
consumption is higher in high temperature condition . Reduction in
feed consumption may lead to weight loss and reduced reproductive performance .
Figure 1: Pattern of feed
intake in pig kept with thermal stress (daily temperature fluctuation = 20 to
350C) – reproduced from Patience et al. .
Figure 2: Pattern of
water intake in pig kept with thermal stress (daily temperature fluctuation =
20 to 350C) - reproduced from Patience et al. .
rate in pigs under thermal stress is up to seven times higher than that in pigs
in thermal comfort (figure 3) [1, 3, 5, 6]. Similarly,
rectal temperature and heat rate are higher in these heat stressed pigs [1, 3, 4, 5, 7]. Partial
pressure of oxygen (pO2) in blood is also decreased during thermal stress.
Figure 3: Effects of heat stress on respiration rate in
pigs at 19:00 o’clock - reproduced from Patience et al. 
swine exposed to thermal stress immediately after breeding have lower
conception rate and higher embryonic death as compared to the animals in
controlled environment [3, 4, 6, 7]. In contrast,
heat stress during mid-pregnancy has less effect to the swine as compared to
animals in early and late pregnancy . Heat stress
during late pregnancy results in larger number of stillbirths and lower birth
weight of new born piglets. Litter size in
pig exposed to high ambient temperature is also smaller . Edwards and
his colleagues  reported that
length of estrus cycle is longer in the swine exposed to thermal stress.
Reduced reproductive efficiency of swine during heat stress is attributable to
alteration in endocrine function of the animals .
Quality of semen (motility and proportion of normal acrosome) has been found to
be deteriorated by high ambient temperature .
animals under thermal stress die at rectal temperature of 430C and
above .Similarly, Escherichia coli in the intestine
of swine became more resistant to antimicrobial drug when exposed to thermal
stress . Incidence of
mycotoxicosis may increase in warm climate due to better growth of fungi in
feed during warm climate [10, 11, 12]. In addition, climatic
warming may establish new vectors of disease which can transmit diseases among
animal populations .
by Yadav Sharma Bajagai "Food Security" is one of major elements of development and poverty alleviation and has been the goal of many international and national public organizations. The issue is so important that according to the state of food insecurity in the world 2012 published by FAO around 870 million people (out of which 852 million from developing countries) are estimated to have been undernourished in the period 2010-12. Although the phrase "Food Security" is being used widely, the definition and concept of food security is elusive and being evolved and expanded over time.
Background Household food deficiency due to low agricultural productivity, limited livelihood opportunities, inefficient food distribution system, weak market linkage, poor infrastructure and lack of awareness among general public about healthy food habit are some of the development challenges in Nepal. Within the country western Nepal suffer more from poverty and hunger with 37% of the people living below the poverty line compared to the national average of 25.16%. Similarly, productivity of major crops is significantly lower than the national average which is already among the lowest in South Asia. Per capita consumption of animal products (32 litres of milk, 7.5 kg of meat and 6.4 eggs per capita per annum) is among the lowest in the region hunger indices pointing to an extremely alarming situation. Household food balance (result of food inflow, household production, household consumption and outflow) is negative almost throughout the year in the region. Government of
by Yadav Sharma Bajagai 1 Introduction Being member of different international organizations, Nepal has many food safety related obligations to comply with rules and regulations of those organizations. Food safety related issues started to become matter of increased concern and one of the priority areas of the government after the country has become member of the world trade organization (WTO) in 2004. Being a developing country, food chains are generally long in developing countries like Nepal as compared to those in developed countries due to poor infrastructure which makes the food more vulnerable to be contaminated with harmful agents (microorganism and chemicals). In addition, infrastructures related to technical regulation, conformity assessment and safety of food are still in developing phase which requires more focus and investment for better functioning. Similarly, Inspections and regulation of food related business are challenging and difficult due