Lectures by xiaoyounan



                        Impact of climate change on livestock
                            Younis, F. E. and Abou El-Ezz, S. S.
  Animal Physiology Department, Animal and Poultry Division, Desert Research Center, Egypt.
The International Fund for Agricultural Development (IFAD) acknowledges climate change as one
of the factors affecting rural poverty and as one of the challenges, it needs to address. While
climate change is a global phenomenon, its negative impacts are more severely felt by poor
people in developing countries who rely heavily on the natural resource base for their
livelihoods. Agriculture and livestock keeping are amongst the most climate-sensitive economic
sectors and rural poor communities are more exposed to the effects of climate change. Livestock
production occupies 70% of agricultural land, and 30% of the ice-free land surface of the planet!
It is responsible for 40% of global agricultural GDP, and is both a contributor to global
environmental problems, and part of the solution.
Climate can affect livestock both directly and indirectly (Adams et al., 1999, McCarthy et al.,
2001). Direct effects from air temperature, humidity, wind speed and other climate factors
influence animal performance such as growth, milk production, wool production and
reproduction. Climate can also affect the quantity and quality of feedstuffs such as pasture,
forage and grain, and the severity and distribution of livestock diseases and parasites.
Global demand for livestock products is expected to double during the first half of this century,
because of the growing human population, and its growing affluence. Over the same period, we
expect big changes in the climate globally. The dramatic expansion of crop production for
biofuels is already impacting on the resources available globally for food production, and hence
on food supply and cost. Food security remains one of the highest priority issues in developing
countries, and livestock production has a key role in many of these countries. However, food
security is re-emerging as an important issue in many developed countries that had previously
regarded it as ‘solved’. These interconnected issues are creating immense pressure on the
planet’s resources.
The IPCC predicts that by 2100 the increase in global average surface temperature may be
between 1.8°C and 4.0°C. With increases of 1.5°C to 2.5°C, approximately 20 to 30 per cent of
plant and animal species are expected to be at risk of extinction (FAO, 2007) with severe
consequences for food security in developing countries. Responses to climate change include (i)
adaptation, to reduce the vulnerability of people and ecosystems to climatic changes, and (ii)
mitigation, to reduce the magnitude of climate change impact in the long term. However, neither
adaptation nor mitigation alone can offset all climate change impacts. To respond to this threat it
will be necessary to focus both on mitigation, to reduce the level of emission of gases
contributing to global warming, and on adaptation, to support local communities in dealing with
the impacts.
Keywords: livestock; Climate change; Adaptation; Mitigation
                                       Why I AM HUNGRY
                              Esmat. A. Seifelnasr and M. S .Saleh
        Physiology & Surgery Departments - Faculty of Veterinary Medicine, Cairo University
 Ghrelin has been purified as an endogenous ligand for GHS-R from rat stomach and named as
 "ghrelin," after a word root ("ghre") meaning "grow". Ghrelin is a peptide hormone in which the
 third amino acid, usually a serine but in some species a threonine, is modified by a fatty acid; this
 modification is essential for ghrelin's activity. The discovery of ghrelin indicates that the release of
 GH from the pituitary might be regulated not only by hypothalamic GH-releasing hormone, but
 also by ghrelin derived from the stomach. In addition, ghrelin stimulates appetite by acting on the
 hypothalamic arcuate nucleus, a region known to control food intake. Ghrelin is orexigenic; it is
 secreted from the stomach and circulates in the bloodstream under fasting conditions, indicating
 that it transmits a hunger signal from the periphery to the central nervous system. Taking into
 account all these activities, ghrelin plays important roles for maintaining GH release and energy
 homeostasis in vertebrates. The predominant source of circulating ghrelin is the gastrointestinal
 tract, primarily from the stomach, but also in smaller amounts from the intestine. The
 hypothalamus in the brain is another significant source of ghrelin; smaller amounts are produced
 in the placenta, kidney, and pituitary gland. Ghrelin's activity in modulating feeding behavior and
 energy balance are best explained by the presence of ghrelin receptors in areas of the
 hypothalamus long known to be involved in appetite regulation. Receptors are also found
 concentrated in other areas of the brain, including the hippocampus and regions known to be
 involved in reward systems (e.g. tegmental area); indeed, ghrelin appears to activate some of the
 same circuits that are involved in drug reward, which may also be related to this hormone's effects
 on appetite. Other effects of ghrelin include stimulating gastric emptying and having a variety of
 positive effects on cardiovascular function (e.g. increased cardiac output). It is not totally clear
 whether the cardiovascular effects are a direct effect of ghrelin or represent an indirect effect of
 ghrelin's ability to stimulate growth hormone secretion.

      ‫اإلرشاد الزراعي ودوره في توعية المزارعين ضد اإلمراض المشتركة بين اإلنسان‬
                         )‫والحيوان( في االراضى الصحراوية والجديدة‬
                                     ‫د/ياسمين أحمد عمار‬
‫يسعى اإلرشاد الزراعي إلى النهوض بمستوى معيشة المزارعين وتحسين مستواهم االقتصادي‬
                                                           .‫من خالل ارتفاع مستوى الدخول‬
‫- من المعروف إن صحة اإلنسان والحيوان مرتبطان وبشكل واضح وذلك نتيجة العالقة بينهما‬
‫سواء بالتربية أو الرفقة ونتيجة لهذه العالقة فإن هناك إمراضا تنتقل من الحيوان لإلنسان وهى‬
‫ماتعرف باإلمراض المشتركة. ومن هنا يبرز أهمية اإلرشاد الزراعي كأحد األجهزة التنموية‬
‫التي تعمل في مجال تنمية المجتمعات الريفية عامة والصحراوية خاصة حيث يعمل على توعية‬
‫المزارعين بطرق الصحية للتعامل المباشر مع الحيوانات ، وأنواع اإلمراض المشتركة وأهمية‬
          .‫التشخيص السليم لتلك اإلمراض والتعاون مع باقي األجهزة المعنية في تلك المجتمعات‬
‫- كما تتع دد الطرق واألساليب اإلرشادية لذلك إثناء التعامل مع المربين وخاصة صغار المربين‬
                              .‫منها الزيارات الميدانية والقوافل واالجتماعات اإلرشادية وغيرها‬
                     . ‫- اهمية االرشاد البيطرى على صحة الحيوان وانتاجيته ، وصحة االنسان‬
‫اقتراح خطة عمل لإلرشاد الزراعي الحيواني(البيطرى) للنهوض وتنمية الثروة الحيواني والحد‬
                                         ‫من انتشار اإلمراض المشتركة بين اإلنسان والحيوان‬

                                     Enigma of Obesity
                                       Adel A. El-Badry
                        Physiology Dept. Fac.Vet.Med., Zagazig University
 Obesity is a word wide problem, for example, the USA spends about 800 million dollars per year
 for obesity researches. Obesity predispose to serious health problems like: diabetes, high blood
 pressure, heart disease, stroke, gallstones, high cholesterol, gout, most types of cancer and may
 lead to death. The causes of obesity are multi-factorial, including dysregulation of food intake
 and imbalance of energy homeostasis. Most physiological processes in the body are simply
 regulated through negative feedback; but the process of food intake appears not to be so simple.
 As the food we eat is not correlated to our body weight but the food produce energy and the
 energy need of the body varies according to different physiological status. The amount of food
 we consume every day is not stable but is subjected to changes due many internal and external
 signals. The internal signaling responsible for adjusting our daily food intake includes many clues
 secreted from different tissues (brain, digestive system, and adipose tissue) most of them are
 hormones or neurotransmitters in brain. The external signals are very important factors in
 increasing or decreasing the amount of food we eat like; Palatability, availability and variety of
 food, cultural factors and also psychological conditions associated with increased or decreased
 food intake.
 The main goal to fight obesity is to AVOID being obese. If you are overweight, try to decrease
 your body weight to normal value not to proceed to the other side and being obese. The body
 mass index (BMI) is an acceptable procedure to evaluate your body weight status. We eat food to
 have energy and the body uses this energy to perform the basic physiological processes like
 digestion, respiration, locomotion, excretion and so on. If the energy in the food we eat exceeds
 that required the rest will be stored as fat. To ovoid fat hoarding, it is important to have energy
 balance, that is to say, the energy income should equal energy output. To decrease our body
 weight we should spend more energy than we consume. As we advance in age our basal
 metabolism slightly decreases while our food intake is kept stable and on the other hand our
 body activities are reduced. This leads to surplus in the available energy that will be deposited as
 fat. To counteract this we must assume an active life style. In addition, we also have bad habits in
 feeding like consuming greater amount of easily digested carbohydrates like white bread, white
 rice, refined sugars and soda drinks plus greater amount of fat like that used for preparing fast
 food meals. Therefore, sedentary life style plus bad feeding habits will surely lead to increase in
 our body weight. We should change our life style being more active, changing our feeding
 pattern toward consuming healthy natural food. For example decrease your intake of white
flower (white bread and pasta) and instead consume whole wheat bread. Decrease the amount
of refined sugar you add to coffee or tea drinks and stop consuming sugary soda drinks and
sweetened fruit drinks; it contains tremendous amount of sugar.
Try not to make sharp rise in blood glucose, as the exta glucose will be stored, by insulin, as fat in
fat depots in the body. Consume carbohydrates with low glycemic index i.e. that produce glucose
slowly due to slower your rate of digestion and absorption, like whole grain, legumes and a lot of
vegetables. We should not starve ourselves but consume small meals at regular intervals, putting
in consideration to avoid junk food like ice cream chocolate and fried food. Also don’t use butter,
ghee and similar dairy products but instead use LOW amount of healthy oils like, canola oils,
linseed or olive oils, remember that these oils are also lipids that will be stored as fat, but their
health benefits is appreciated.
Do not forget to drink water all the time, as the body is water medium and all the chemical
process performed by our tissues occurs in a water media. Drink one to two water cups before
meal that will fill the stomach partially and decrease the volume of meal you eat. Between
meals, you can eat low calories food like fresh vegetables (cucumber, lettuce, carrot) which in
addition to fruits had low glycemic load.
Remember to make some exercise every day these activity should be aerobic one and don’t
fatigue yourself, but steadily increase your physical activity, this plus its eminent effect on your
weight will also improve your health status. This is important issue to reduce your body weight,
as regular exercise will raise the basal metabolism, which means more calories burning, and
consequently decrease in body fat stores.

                                     TRUST IN A BOTTLE
                             Esmat A. Seifelnasr and M. S. Saleh
       Physiology & Surgery Deprtments Faculty of Veterinary Medicine, Cairo University
Oxytocin has been labeled the 'love hormone', the 'bonding hormone' and 'trust in a bottle'.
Oxytocin is a hormone and neurotransmitter which is secreted from the hypothalamic nuclei and
reserved in the posterior pituitary gland. Oxytocin has the distinction of being the very first
polypeptide hormone to be sequenced and synthesized biochemically by Vincent du Vigneaud et
al. in 1953. According to a recent article in Nature, oxytocin is a neuropeptide that plays a key role
in social attachment and affiliation in both humans and non-human mammals. Oxytocin has both
peripheral hormonal effects and actions in the brain. It has been shown to mediate trust, love and
bonding. Although oxytocin is produced in both males and females and its receptors are found all
over the brain and reproductive systems of both sexes, name oxytocin is derived from the Greek
for "swift birth". If hormones could win popularity contests, oxytocin might well be queen of the
day. Oxytocin, which is naturally produced in the hypothalamus in the brain, stimulates uterine
contractions, and allows the breast to "let down "milk in pregnant and lactating female. Oxytocin
is released in the body naturally during child birth and when engaging in sexual relations.
Oxytocin affects several behaviors such as trust, empathy, and generosity. Recently the hormone
was improved to be one of the most effective therapeutic treatments for autism. Administration of
oxytocin allowed autistic patients to adjust to their social context. Oxytocin also reduced their fear
of others and promoted closer social relations. Some tout it as an elixir that makes you more
likeable, trustworthy and attractive.

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