In recent years, the welfare of farm animals during transport has been emphasized due to the importance of this activity for the farming industry. Many researchers have indicated that transportation by road or air, or by short or long journeys can be stressful to animals which can be inferred from the behavioral and physiological changes of the animal. One of these stresses is motion. The motion experience in sea transport is different from the motion of trucks (Phillips, 2008).
It is indicated that it is widely known that there are specific characteristics of the movement of ships that lead to the individual to feel sea sickness, but in spite of the age of the problem, it has not been defined yet the precise nature relation of the ship movement with the seasickness (4"Lawther and Griffin 1986). Stress affects the biology function of animals (2"Moberg and Mench, 2000). One of these biologyical is metabolisim that is alterted when the animals are exposed to stress (2"Moberg and Mench, 2000).
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In recent years, there has been temporary restriction the feeding of animals before transport became popular in Australia in order to reduce the accumulation of animal waste in vehicles (4"Jim and Phillips, 2008). This view is supported by 2"Hogan et al., 2007 who studies the physiological and metabolic impacts on sheep and cattle of feed and water deprivation before and during transport.
Exposure animal suddenly and temporarily to restriction of food and water that provided its sufficient nutrition requirement regarded stressor. It is reported that motion sickness probably is not affected by a period of food deprivation before transport but might reduce vomiting (SCAHAW. 2002).
A considerable amount of literature has been published on the stressors that involved during road transport conditions. However, the impact of stressors of sea transport motions on sheep welfare synchronocity with feed consumption has not been reviewed.
The hypothesis of this report as following:
Do heave and roll motions have an effects on sheep's welfare, heart rate's, on rumination's, synchronocity with feed consumption.
Does roll and heave motions have an effect on sheep behavior, including standing , eating, lying and drinking, and their synchronocity with feed consumption.
Does an additive anti-emetic in the diet on the roll and heave motions have an effect on sheep welfare as demonstrated by changes in feed consumption.
Animals welfare and its health has most important thought through the export chain of Australia's livestock (7"Ransley, 2008). The welfare domestic animals including health and well-being are affected by the severe environmental conditions that lead the animal exposure to stress (2"Moberg and Mench 2000; Broom 2008; Cockram 2007). Although some of these responses are often examined during animal transport, it has not determined conclusive evidence yet which phase of transport cause these responses (Hall 1998). For instance, it has not proved the causes of travel sickness observed in pigs which might be result from noise, vibration and whether from another factor or the combination of factors (Hall 1998). Apparently, it is reported that it is difficult to study the transport of livestock due to the fact that the response of animal may occur because one factor or combination of factors (Hall and Bradshaw 1998). It is reported that stress induced by transport change the immune function of the animal (Hall 1998). This agreed with 2"Moberg and Mench (2000) who suggested that host immune function is altered directly due to the stressors induced during transportation. They explained that these alterations is linked to the disturbances in the HPA axis and the hypothalamic autonomic nervous system. Other studies emphasized that exposure animal to stress induce alteration to the biological function of animal such as metabolism and behavior (2"Moberg and Mench, 2000).
Short-term interruption of nutrients that animal is supplied coincided with feed and water deprivation (FWD) associated with stressor of transportation will affect particularly the function of the rumen and the rest of the digestive tract, tissue homeostasis and control of enteropathogenic bacteria by rumen microbes (2"Hogan et al., 2007).
A considerable amount of studies have investigated the effect of stressors on welfare of sheep and ruminants during road transportation; however, little is known about sea transport, such as the motions produced by ships and their impact on sheep feed consumption. In sheep, published research has examined the effect of stressor on its welfare; however, no data exist for the effect of sea transport motion on animal well- being through behavioral and metabolic compromise. It is clear that some experiments in the literature with domestic animal in particular ruminants are needed to be analyzed which transport motion heave or roll is affected on animal welfare. Therefore, this report research project is to identify the effect of sea transport motion on the behavior and metabolic coincide with feed consumption.
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This literature is divided into four parts. The first part reviews the concepts of animal's transportation from different kind of ways in general and in particular, the sea transportation and the important of this subject on the animal welfare. The second part reviews the potential stressor that involved during animal transportation.
The third part review the transport motions that produced by ship considered the most import sea transport motions in terms of their capacity to produce motion sickness, How is motion sickness produced, the impact of motion sickness on animals and human and the main physiological and behavioral responses of animals to motion sickness.
The forth part review the impact of stress in general on the digestive of the animals and the transport stress on the digestive of animals in particular. These reviews rely comprehensively on aspects that have been studied on ruminant animals in general and particularly on sheep.
. The General concept of the animal transport and its welfare
Recently, there has been given considerable attention to the welfare of animals during transport (Knowles & Warriss 2007) and in particular export sheep during sea transport (3"Higgs, 1999). This is due to the fact that there are higher death rates for animals during export from one country to another (Black et al. 1993) although there is an improvement in the welfare of animal in recent years (3"Higgs, 1999). Black et al (1993) reported that the average mortality rate of sheep in over 50 voyages when exported from New Zealand to the Middle East was 2% and sometimes the percentage reached 5-10% occasionally. Similarly, it is reported that mortality is greatest with the export of live sheep and cattle from Australia to the Middle East by ship (Phillips, 2008 and Knowles & Warriss 2007) which has encouraged the Australian government to finance research to study the problem (Knowles & Warriss 2007) as well the European Union (EU) fund research about the welfare of sheep during transport (Earl 2008) beside, there has a considerbal research has been conducted to investagate the reason of death in the voyes and reduce the losses (3"Higgs, 1999). This lead to a rapid increase in public concern for the welfare of the animals (Black et al. 1993 & Phillips 2008 and 2"Tadich et al., 2009), in particular animals exported to developed countries (Phillips, 2008).
2.2.1 Australian live export
Australian trade of live animals is the largest trade in the world, it exported approximate 1, 6 and 0.1 million of cattle, sheep and goats respectively from 18 seaports to more than 40 overseas countries, which is most of them from the Middle East and South-east Asia (Phillips, 2008). It is reported that the Australian live sheep export happen an rapid increase (Norris and Richards 1989). The export is from Australia to Sangafora and middle east (Norris and Richards 1989). The authors reported depending on the Australian Bureau of Statistics that in 1975 the export increase from less than 2 millon to reache 6 millon in 1980 and then in 1986 and 1987 the export increase slightly to reach 7.8 million. Some of countries such as Australia, New Zealand export Millions of live ruminants to the Middle East because the factors of religious and cultural in these regions contributed to demanding for enormous numbers of live ruminants, in particularly sheep (Abdul Rahman 2008).
After incidents on two high profile voyages, the live export industry was reviewed and the industry standards rewritten in an effort to prevent further accident (7"Ransley, 2008). Animal welfare standers can be the technical barrier to the international commercialisation of export live sheep (2"Tadich et al., 2009).
Expoert live sheep is an important to the Austrailain economy (3"Higgs, 1999 and Agra CEAS Consulting Ltd 2008 ). Economic gains and meat quality can be affected because of animals transport (2"Miranda-de la Lama et al., 2011). Scharp 1988 reported that welfare of animal associated with the trade, the trade of sheep and its import decreased by the largest importer country such as Saudi Arabia decreased its import of sheep from 7 million head in 1988 to 3 million head in 1990. The live sheep export of Australia was low in 2004 due to the Sudia Arabia rejection of an Australaian vessel (Agra CEAS Consulting Ltd 2008 ). From 1990 to 2005, The live sheep exports in austrailai has been reported by Agra CEAS Consulting Ltd (2008 ) using the survey of Australian Bureau of Statistics (ABS) as shown in figure (1) (Agra CEAS Consulting Ltd 2008 ).
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Figure 1. Australian live sheep exports by value (AUS$) and volume (head) (Agra CEAS Consulting Ltd 2008 ).
2.2.2 The welfare of animal
The definition of the animals welfare have been reported by many authors (Appleby 2008; Broom 2008 and Knowles & Warriss 2007). Animal's welfare is defined an as the individual state that the animal is trying to deal with its environment (Knowles & Warriss 2007 and Broom 2008). These changes means that an animal needs a major effort to maintain homeostasis through changes that occur to the animal behaviorally and physiologically. Following these changes the animal needs to make a further effort to deal with the environment. In this stage the welfare of animal is likely to be poor (Knowles & Warriss 2007). Appleby in (2008) defind the welfare as a term in wide meaning consist the physical of animal body and the process of animal thinking to maintain healthy and comfortable.
Animals health is important part of welfare, if the diseases is increase that means the welfare is poor (Manteca 2008). The author reported that animal welfare might be compromised by the vehicle vibration, the jolting, shocks, and sudden impacts caused by road conditions and driving skill. the immune system of animal might be affected by the stress which might result in increasing the infection and infectiousness between the animals (Manteca 2008).
mortality is an indicator of the difficulties that effects on animal welfare for along period of time (broom 2008) and dead of animals indicate the mechanisms of animal physiological failed to remain the homeostasis due to stress (Knowles & Warriss 2007). Simalrly 3"Higgs (1999) reported that it can be used the mortility to identify the regions and group of sheep when transported by sea which are exposed to the risk of suffering of being the death rates higher. In the survey of sheep death rate, Scharp (1988) reported that 21109 sheep death during entering feedlots in thirty three shipments comprising 702627 head sheep.
In the literature of 6"Nielsen et al (2011) reviewed that it has found that transport sheep decrease their resistance to diseases, such as the Infection of pneumonia and salmonella and also increase mortality. Adams and Sanders (1992) reviewed the literature from the period and found that sheep were observed not eaten when they were accumulated into feedlots to be transported by sea. In their work of stimulation feed intake of sheep by using antiemetic dexamethasone, Sanders and Adams (1992) proposed that the sheep failure to eat is not clear but it is often due to stress. Sanders and Adams (1992)also suggested that inanition or salmonellosis are more likely to be the causes for death of the sheep during shipment overseas. This view is supported by 6"Norris et al. (1992) who write that sheep failure to eat pellet led to inanition and salmonellosis which are the two causes of death sheep during shipments overseas. It is reported that half of all death sheep during sea transport because of inappetence and fifth of death sheep due to salmonellosis (Phillips 2008). Earl (2008) added trauma to the causes of death that mentioned above. Adams and Sanders (1992) suggested that feed intake could be improved to reduce the losses by injection the sheep with antiemetic. However, an investigation of sheep dying while transportation through sea from Fremantle, Western Australia to the Middle East conducting by 4"Jelinek et al. (1982) found that in the first 13 days of ship transportation, 204 sheep died because of prevalence of salmonella. This investigation is certain that there is a significant mortality of sheep during period of assembling and transportation. Indeed, measures should be taken to improve the welfare of animals through reducing the stressors that the animals faced during Mustering, restriction of food and water, road transport, Loading, Journey transport (4"Jelinek et al. 1982).
2.3 Ruminants face several stressors during transport
The export process does not only include the transfer of animals by sea, where the process begins with the mustering of animals in some cases on remote land and it finish in the slaughter of animals in the country of destination and this process is taken almost between one month to two months (Phillips, 2008). The author also revealed that sea journey is take from 7 days to South-east Asia and 23 days to the Middle East. Therefore, the welfare of animals and their health can be reduced when they transported due to exposure these animals to several of potential stressors (2"Miranda-de la Lama et al., 2011). The author reported that a considerable amount of literature had been studied about the stressor that faced animals such as the sheep and lamp during transport (2"Miranda-de la Lama et al., 2011). Similarly, a number of studies have considered the welfare factors that affected the live sheep export industry (5"Scharp, 1992; Cockram 2007). The stressors that the live export exposed in sea transport are stocking density, noise , ammonia , heat stress , neophobia and motion (Phillips, 2008). The author summarized the stressors that experienced from animals before embarkation of the ship. These are :
1-Mustering included (horsemen, helicopters, dogs, riders of motorbikes and allterrain vehicles).
2- Curfewing - restricting food and water start before they are transported.
3- Road or rail transport for up to 50 h.
4- Loading, unloading and transfer to a pre-export assembly depot.
5-Road transport to the port.
6-Loading into the ship.
Consideration has been concentrated on these stressful (Earl 2008) such as changing in the temperature , noise and vibration which many of these stressful might be lead the animals to death (2"Miranda-de la Lama et al., 2011; Kent 1997; Manteca 2008). Regarding the noise, in review of Grandin 2007 reported that the noise surrounding the sheep during transport appeared to have a little effect on them (Grandin 2007). He reported that sheep did not go away from the noise source (noise generator) and did not show any behavioral changes indicative of discomfort as a result of noise exposure. In addition, noise is less likely to stimulate increase in heart rates in sheep than vibration (Hall 1998). Phillips (2008) revealed that a number of changes to the environment can cause stress to animals represented by fear and anxiety. Other study have focused on the stressors of deprivation of food and water , loading and unloading, differing space allowances, duration of journey times (Earl 2008). Researchers have confirmed that transportation of animals over long distances by sea imposes more stress than short journeys (Phillips, 2008).
A considerable amount of literature has been published on the adverse affect of duration transportation on the animal up to 24h ( Knowles et al. 1995 ), 31 h (5"Knowles et al., 1999) and 48 h (2"Tadich et al., 2009; Fisher et al., 2010). The finding of study conducting by 4"Krawczel et al. (2008) indicated that in both of case the animal are provided rest time or transported without stoping , lambs experienced some stress when they are transported for a long journey. `
in compare with sea transport, transport by land is well understand (Philip 2008). He reported that the duration of journey through sea transport is a long; it might take 2-3 weeks. In literature of stress in sheep, Kent 1997 indicated that sheep are stressed in the begging of journey. However, this stress is reduced in some animals transport by sea in the latter of the journey due to the adaptation to the conditions from the animals (Philip 2008).
A study conducted by 2"Miranda-de la Lama et al (2011) to determine the effect of pave (PR) and unpaved road (UR) on plasma stress indicators and meat quality of the lamb when they transported for 3 hours, the findings found cortisol, lactate, glucose, and CK levels and a higher N/L ratio were considerably higher in UR lambs than PR lambs. The meat quality of UR lambs was darker color,higher ultimate pH and higher tenderness values than PR. In conclude, lambs of unpaved roads transported had a more strong stress response and poorer meat quality than lambs of paved roads transported.
Handling by human is one of the stressors that the animals faced which lead the animal feels fears (Kent 1997; Manteca 2008; Grandin 2007 and Broom 2003).
2.4 The behavioural and physiological measurements due to the stressor of transport.
It is stated that the behavioural and physical changes are the indicator that animal exposed to stress (2"Siegel and Gross, 2000). It is stated that the behavioural and physiological measurements can be inference that sheep and other animal such as pigs exposed to stress during transport (Hall and Bradshaw 1998). The measures of these behavioral given sensitive indicators of changes that observed on welfare of the sheep which transported through shipments from New Zealand to Saudi Arabia (Black et al. 1993).
Animal physiological response to severe environmental conditions such as the stressors that may encounter during handling and transport will affect the Physiological and anatomical structure of animal body (Broom 2008). The concentration of blood constituents, such as cortisol, glucose (GLU), plasma urea N (PUN), and creatine kinase (CK) are the physiological response that observed during road transport (7"Zhong 7"et al., 2011). Physiological indicators of stress during transport is summarised in the Scientific Committee on Animal Health and Animal Welfare (SCAHAW. 2002) and the review of the welfare of livestock during road transport by Broom 2008, as shown in Table ( 1 ).
Table 1 physiological indicators of stress during transport (SCAHAW. 2002 and Broom 2003, 2008 ).
Measured in blood or other body fluids
â†‘ FFA, â†‘ ß-OHB, â†“ glucose, â†‘urea
â†‘ Osmolality, â†‘ total protein,
â†‘ albumin, â†‘ PCV
â†‘ CK, â†‘ lactate
Fear/arousal and physical
â†‘Heart rate, heart rate variability â†‘,
Body temperature, skin temperature
FFA, free fatty acids; ß-OHB, ß-hydroxybutyrate; PCV, packed-cell volume; CK, creatine kinase.
Numbers of observations of the different behaviours were, lying, standing ruminating, standing, standing with the head down (Hall and Bradshaw 1998). The behavior of sheep and pigs were observed in total number of minutes include lying, standing or walking (Bradshaw et al 1996).
Many of these stressors have been studied on road transport, in particular motion have studied in road transport; however, it have not studied the effect of motion produced by ship on the welfare of livestock animal.
2.5. The transport motions that produced by ship
The motion experience in sea transport is different from the motion of trucks (Phillips, 2008).
It is indicated that it is widely known that there are specific characteristics of the movement of ships that lead to the individual to feel sea sickness, but in spite of the age of the problem, it has not been defined yet the precise nature relation of the ship movement with the seasickness (4"Lawther and Griffin 1986).
It has been indicated that ships might move in Six axes each axis independently of the other these are divided into three translational axis (x, y and z) and three rotational axis (roll, pitch and yaw) as shown in figure (4"Lawther and Griffin 1986). This author has measured the ship motion, resulting in passengers experienced seasickness. 40%percentage of vomiting incidence from the data of 17 voyages involving 4915 passengers was highly correlated with Vertical motion (4"Lawther and Griffin 1986).
Figure 1. Axes of ship motion (4"Lawther and Griffin 1986).
It is reported that the highest occurrence of motion sickness has been found when used different motion profiles in regards to heave, pitch and roll (Dahlman 2009). indicated that many authors have been set up experiments with the ship motion to investigate which kind of ship motion are more likely to cause motion sickness. These studies found that the only component of the movement that led to the motion sickness was vertical movement (heave motion) (1"Bles et al., 1998). This similar to the finding of study reported by Griffin (1990) who discovered the motion sickness occurrence produced by ship motion in practical about the human. It is reported that the motion sickness incidence correspond with the vertical motion of the ship . 6 % of motion sickness would be appeared with the heave motion alone (Griffin 1990). (1"Bles et al., 1998) review in his study showed that the incidence of motion sickness considerably increased with the combinations of heave motion with pitch and roll motion.
In a study conducting by 6"Wertheim et al. 1998 indicated that heave motion characteristics provoke sea sickness uniquely compare to pitch and roll movements which were not effective. In an experiment with a ship motion, It has been exposed subjects (people) to pitch and roll motion once alone and other time combined with small heave motion to investigate their effect on motion sickness (6"Wertheim et al. 1998). The result matched with the traditional claim that motion sickness was produced by only heave motion not by pitch and roll. The author assume that pitch only and roll only have a small effect to provoke motion sickness ; however, when they combined pitch with small ( weak ) heave and roll with small (weak) heave motion, the effect can be dramatic even if the heave motion was weak. He reported that this finding is matched the previous study by McCauley et al in Motion sickness incidence: Exploratory studies of habituation, pitch and roll, and the refinement of a mathematical model.
It has been stated that vibration is a strong stressor and has direct physiological effects (Hall and Bradshaw 1998). Vibration is one aspect of motion and is characterised by direction (horizontal, vertical and geophysical), acceleration, and frequency (Hall and Bradshaw 1998). In pig studies it is reported that vibration and random motion may induce nausea, discomfort, fatigue and distress (Earley et al. 2011) and cause motion sickness in some animals (Hall 1998).
2.6 What is motion sickness and How is produced
Motion sickness is one of the most serious problems in the field of transport (Merhi 2009). It is well known that motion sickness affects animals and humans whether they are transported by land, air or sea (Golding 2006 and Merhi 2009). Motion sickness is one of the most common diseases that can affect the animal (Merhi 2009). However, Dahlman (2009) has different perspective about the motion sickness is not an illness. The author reported that motion sickness is the autonomic response naturally to unfamiliar or specific stimulus; the individual has limited ability to perform tasks or duties under the influence of motion sickness.
Humans and some other species get sick when they are exposed to motion sickness (Bos et al. 2008). The sensory conflict theory mostly explains motion sickness (Turner and Griffin 1999). It starts with the autonomic nervous system (ANS) change result in conflict detected by individual visual or vestibular organs (Dahlman 2009). It is suggested that the misinterpretation of concurrent sensory input from the visual and vestibular system lead to motion sickness (Turner and Griffin 1999). This disturbance disturbs the balance in the (ANS) between the two the sympathetic and parasympathetic nervous systems which are subdivisions of the ANS, result in increasing parasympathetic activity and decreasing sympathetic system act (Dahlman 2009).
This sickness results in feelings of malaise and other symptoms such as pallor, sweating, nausea, and in the end vomiting (2"Holmes and Griffin, 2001; Bos et al., 2008 ; 1"Dai et al., 2011 and Dahlman, 2009). Pallor is commonly sign of motion sickness which is the result of Pallor is the result of a parasympathetic withdrawal and the vasoconstriction (Dahlman 2009).
it is also indicated that stomach awareness is also symptoms of motion sickness (Dahlman 2009).
Gastric activity is other symptoms of motion sickness (Dahlman 2009). Its function in normal condition under controlled by the autonomic nervous system and oscillates around a frequency of 0.05 Hz (3 cycles/minute) in human. The resignation of gastric activity occurs when people exposed to a motion sickness. In this stage, the consequences of an autonomic nervous system response, the pylorus is closed and prevent any content pass through to the duodenum. This situation involve also fear, swinging or rotation of the head and, in some cases , gastric motility shut down completely and provoked nausea (Dahlman 2009).
There are other symptoms of travel sickness which can be summarized such as sniffing, foaming at the mouth, chomping, and retching or vomiting (Randall and Bradshaw 1998) which these symptoms observed in pigs when studied the effect of travel sickness on them (Bradshaw et al. 1999). Nausea and vomiting are the most common symptoms that the components of the body's defensive response to motion sickness (Andrews 1988 and 2"Holmes and Griffin, 2001). Profuse salivation is one of the main prodromal indications of vomiting (Andrews 1988 and 2"Holmes and Griffin, 2001). Animals try to clear this saliva by excessive swallowing which also observed prior to vomiting. The saliva of ruminant animals appears prior to vomiting, most probably to provide protection against the acidic material (Andrews 1988). The salivary glands are innervated by the facial and glossopharyngeal nerves which have their cell bodies in the PCRF (the putative vomiting centre) (Andrews 1988).
The response to motion sickness is linked with the function of the vestibular system (Golding 2006) which is play important role to produce motion sickness (1"Dai et al., 2011). Motion sickness attribute to the fact that the autonomic system is activated due to response to vestibular stimuli (1"Dai et al., 2011). Motion sickness is the phenomenon of self-inflicted maladaptation. It occurs at the beginning and ending of conditions of sensory reorganization when the pattern of inputs from the vestibular system, other proprioceptors and vision is at variance with the stored patterns resulting from recent transactions with the spatial environment (Bos et al. 2008). This is supported by 1"Bles et al. (1998) who reported that provoked motion sickness in all situations is distinguished. This characterizing operate by a condition in which the sensed vertical as determined on the basis of integrated information from the eyes, the vestibular system and the nonvestibular proprioceptors is at variance with the subjective vertical as expected from previous experience. the theory of motion sickness supported by the latter authors who indicated the cause of seasickness due to the conflict of sensory information either between the visual and vestibular systems or within the vestibular system itself (4"Lawther and Griffin 1986).
Spatial orientation, maintenance of balance, and stabilizing of vision through vestibular-ocular reflexes are the primary functions of the vestibular system. However, it has been proposed an additional function for the vestibular is that it acts as a toxin detector (Golding 2006).
It is assumed that emetic or vomiting is the response of animals and people to motion sickness (Andrews 1988 and Golding 2006). This emetic response is considered the protection of animals and people from harmful and toxic substances that can be swallowed (Andrews 1988 and Golding 2006). This hypothesis of the toxin detector suggests that the brain has developed to distinguish any derangement of expected patterns of vestibular, visual, and kina esthetic information as evidence of central nervous system malfunction and to initiate vomiting as a defence against a possible ingested neurotoxin (Andrews 1988 and Golding 2006).
The emetic mechanism function has been demonstrated (1"Dukes et al., 1993). He revealed that the medulla is the part where the functional of emetic mechanism are located. The vomiting centre and the chemoreceptor trigger zone (CTZ) are two of anatomically and functionally distinct units (1"Dukes et al., 1993). The reticular formation and the floor of the fourth ventricle are where the vomiting centre and the chemoreceptor trigger zone located receptively (1"Dukes et al., 1993). The gastrointestinal tract has visceral afferent impulses arising anywhere which is responsible for direct activate for the vomiting centre (1"Dukes et al., 1993). The efferent motor nerves are cranial nerves to the upper gastrointestinal tract and the spinal nerves to the diaphragm and abdominal muscles (1"Dukes et al., 1993). The CTZ on the other hand receives central stimulation from chemical substances such as morphine, apomorphine , cardiac glycosides and copper sulfate (1"Dukes et al., 1993). The CTZ do not have the ability to cause vomiting without the connections to the vomiting center (1"Dukes et al., 1993). Thus CTZ is a dependent station on the commence of the vomiting act. Therefore, the mediation of the response of all emetic is through the vomiting center. It has been generally suggested the Sensory conflict theory to clarify the cause of motion sickness, but the nature of the conflict is not precisely known (1"Dai et al., 2011).
Motion impact on welfare of animals
Motion can be caused by a variety of motion environments (Golding 2006). Several stressors such as movement have not been studied compared with other stressors (i.e heat stress) have been studied widely (5"Ruiz-de-la-Torre et al. 2001). It has not been done any researches about the impact of ship movements on the welfare of sheep (5"Ruiz-de-la-Torre et al. 2001). The effects of motion and vibration produced by vehicle on the sheep response to stress during transport have been studied in many literatures (5"Ruiz-de-la-Torre et al. 2001). It is reported that vibration has recognized that vibration might induce fear, nausea, distress and fatigue in man and some of other mammals due to the fact that the distribution of the oscillatory motions and forces within the body (Carlisle et al., 1998).
Ruiz-de-la-Torre et al.(2001) indicated that motion sickness can be noticed in animals when the movement of the vehicle induce them to and fro movements to the animals. In journeys in which vibration characteristics is certain, it is observed in pigs behavioural evidence of motion sickness when they retch and vomit (Hall 1998).
Frequency, magnitude, direction, and duration of the movement are factors that influenced motion sickness during transport (Joseph and Griffin 2007). Low-frequency vertical oscillation can cause Sickness in some ships (4"Lawther and Griffin 1986). The response of individual is associated to certain frequency (1998). For example, when vertical motion center on 0.2 Hz frequency, it most likely to induce motion sickness; however, it is not known the responses of sheep and pigs to different frequencies (Hall 1998). However, Randall and Bradshaw have reported in their study about the effect of vehicle and motion sickness in1998 that human experienced Low frequency oscillatory motion (0-05 to 0-5 Hz) in ships and road vehicles which cause motion sickness. Others found motion sickness between 0.15 and 0.25 Hz (Dahlman 2009). It is clear that vehicle and trailers in which use commonly and carried animals; the transmit of vibrations to the body of animals is significantly different (Hall and Bradshaw 1998).
There have been very few studies of the incidence of motion sickness in pigs and none which has attempted to identify the frequencies of motion of transporters which are likely to be implicated (Randall and Bradshaw 1998).
In literature of Balance and Posture Control review by Nashner (2009) define the balance as the mechanisms that individual try to maintain stable during their dairy life. The driving quality possible causes a few problems for the animals because of the difficulties encountered by the animal to maintain balance (Broom 2008). This is supported by Cockram (2004) who reported that the style of driving significantly influence on the welfare of the animals when the ability of the sheep disturbed to rest.
It has been reported that the animals tend to lie down only when they feel the increasing of the risk to animal from the closing proximity of other animals and the vehicle movement (5"Knowles et al., 1999). It has been reported that when cattle standing for long time during its transport, it would be assumed that the levels of motion and vibration do impact on their welfare (Earley et al. 2011). Simalrly, Broom (2008) reported that sheep and cattle stand if the situation is disturbing but they try to lie down if it is not (Broom 2008). The animals tend to stand parallel to each other and at right angles to the direction of travel of the train facing indiscriminately in either direction (2"Moss, 1982). The orientation of cattle to direction of travel during transport tends to be perpendicular or parallel., cattle prefer to stand perpendicular rather than parallel to the direction of motion when their stocking density is medium or low (Swanson and Tesch 2001).
On rough journey, sheep are needed more space allowances to keep their balance (SCAHAW. 2002). It is mostly a problem to keep posture and Balance in high frequency movement which motion sickness occur (Dahlman 2009).
The drugs currently used against motion sickness were identified in the study conducted by Golding and Gresty (2005) who indicated that the new neurokinin NK1 receptor antagonists are potent broadband anti-emetics, highly effective against motion sickness (vomiting) in animals, but unfortunately ineffective against motion induced nausea in man.
2.6.2 The response of animals to motion sickness
The effect of motion on human can be determined by questionare the passenger who travel through the ship (4"Lawther and Griffin 1986). however, in animal ,its behavior is the obvious indicator that show they have difficulties coping with transport ( Broom 2008) .
In a few studies, It have been made the link between the behavioral observations and physiological processes (Hall 1998). For instance, in pigs, the higher level of plasma lysine vasopressin (LVP) is correlated with vomiting (Hall 1998). This is supported by Knowles and Warriss (2007) who indicated that the increasing levels of vasopressin used as an indicator of nausea and vomiting.
Vibration may be observed as signal of motion sickness in pigs (Hall 1998). The author stated that vibration is a physiological associate with nausea in animals that vomit, enhanced the increasing of secretion plasma LVP concentrations in pigs and man during transport.
SCAHAW (2002) indicated that when humans report that they have feeling of nausea linked with physical signs of motion sickness, the blood test show increasing in vasopressin. SCAHAW (2002) indicated that Pigs also show motion sickness, retched and the gut contents ejected, in particular when they travel along roads with wind. This report also indicated that in pigs vomiting and retching increased correspond with the elevation of the levels of lysine vasopressin.
There is evidence but it is not based on the facts that stress in cattle and sheep is caused by high seas and there is also an evidence of motion sickness in that the quadrupeds and pigs when they are transported by trucks. In the latter could be due to fear and anxiety rather than motion sickness. Interestingly rats show pica not vomiting during motion sickness. Consequently, it could be guessed that inappetence occur in animal due to motion sickness (Phillips 2008).
As mentioned above, during journeys, humans and pigs are subjected to motion sickness which lead to linked with the elevation concentrations level of plasma vasopressin and retching in the blood; however, although ruminants do not show retching it might still be affected by motion sickness (SCAHAW. 2002) and there is not clear evidence available about sheep that vomit or no (Hall 1998). The author reported that sheep probably do not vomit except in special occasion when they recover from general anaesthesia. However, it has been suggested that the observation of rumination inhibition in sheep indicated travel sickness (Hall and Bradshaw 1998). In horse, the vomiting is enormously rare (1"Dukes et al., 1993). However, there is no evidence for motion sickness has been found in sheep, unlike pigs, but because ruminants do not vomit, this comparison is very hard to determine (Earl 2008). It has been reported that the vomiting in ruminants does not appeare in the usual sense but occurs when the contents in abomasal ejected into the forestomach (1"Dukes et al., 1993).
Heart rate variability (HRV) specifically the high frequency range was used to study the response of the autonomic nervous system to motion sickness. The findings confirm gradual sympathetic activation with increasing nausea and increasing in vagal tone before strong nausea (2"LaCount et al. 2009).
It is used heart rate as an indicator of motion sickness. It is reported that heart rate increase during nausea However, little attention has been received about the relationship between heart rate and subjective ratings of motion sickness and the autonomic origins of any increase in heart rate during motion sickness are unknown (2"Holmes and Griffin, 2001).
2.6.3 The effect of motion sickness on Ruminants behavior
it has been indicated that rumination behavior is ejecting the contents of the rumen stomach through the mouth which this process is called (regurgitate) and then then this content masticate again after grinding by the movement of the jaw (1"Dukes et al., 1993). It is reported that the cause of vomiting and regurgitation are similar (1"Dukes et al., 1993). The development of negative esophageal pressure is when a deep inspiration occurs with a closed glottis (1"Dukes et al., 1993). The reticulum has touch receptors. The coarse forage stimulates these receptors which lead to activate a medullary reflex that controls rumination (1"Dukes et HYPERLINK "#_ENREF_1"al., 1993). The temporarily interruption for rumination can be due to many situation such as hunger, fear, pain, curiosity or strong social connections (1"Dukes et al., 1993).
The great reduction of rumination is noticed when animals exposed to FWD and practically it stopped for 24 hours (1"Dukes et al., 1993; 2"Hogan et al., 2007). Drinking water from animals induced by eating therefore, when animals exposed to (FWD), it will remove the stimulus to drink which is stimulated by eating (2"Hogan et al., 2007). Consequently, salivate which is important to associate with eating and rumination its stimulation is removed by FWD (2"Hogan et al., 2007). It has been observed loss of appetite for a small proportion of sheep that have been transferred for a long time shipments from Australia to the Middle East for 10 hours to 14 days (4"Jim and Phillips, 2008).
It is reported that the appetite reduction when ruminants exposed to heat stress result from the increasing of body temperature and secondly it might be due to increase in gut fill (Nissim Silanikove 1992).
These symptoms observed in sheep probably developed symptoms similar to the anorexia nervosa in humans that is associated with depression, anxiety and negative effects (4"Jim and Phillips, 2008). Also it is reported transport is stress the animal which cause changes in appetite (Earley et al. 2011).
It is reported that motion sickness probably is not affected by a period of food deprivation before transport but might reduce vomiting (SCAHAW. 2002). It is known that healthy, untransported sheep can tolerate feed and water withdrawal periods of up to 2 to 3 d. it is indicated that sheep have a large reservoir of water and metabolites in the rumen in which contributed them to tolerant the deprivation of food and water for long periods (Kent 1997). This is supported by 3"Fisher et al., (2010) who stated that the healthy sheep can be tolerant to DFW for up from 2 to 3 days. It is concluded that the data indicated that sheep tolerate hunger and water deprivation extremely well. He concluded that DFW is not linked with the sheep stress during transport.
There is evidence but it is not based on the facts that stress in cattle and sheep is caused by high seas and there is also an evidence of motion sickness in that the quadrupeds and pigs when they are transported by trucks. In the latter could be due to fear and anxiety rather than motion sickness. Interestingly rats show pica not vomiting during motion sickness and it can therefore be guessed that motion sickness may attribute the appetite of animal to decrease (Phillips 2008).
2.7 The impact of stress in general on the digestive system
It is important to know the biology of the stress response in order to know the relationship with the diseases (Manteca 2008). it is suggested that (2"Siegel and Gross, 2000) It is described that the organism of the sympatho-adrenomedullary system response to stress in order to keep the homeostasis reguler when the animals are threatened by the challenges of the environment (Manteca 2008). Sejrsen et. al. 2004 reported that the activity of the hypothalamic-pituitary-adrenal HPA-axis can be changed by feeding and fasting of ruminants animals. It has been reported that some works have defined stressors and indicated the sign of stress on animal when is (HPA) axis, promoting secretion of cortisol, corticosterone, adrenaline (also known as epinephrine), or noradrenaline norepinephrine are activated effectively by noxious stimuli , resulting in abnormal increases in cortisol ( Hall 1998; Hall and Bradshaw 1998; 1"Balm 1999 and Manteca 2008). There are many areas in the brain organize the responsing to threating stimuli such as these areas are Neurons in the hypothalamus which is the main area in the brain related to stress response (Manteca 2008). the stress response is mediated by corticotrophin releasing factor (CRF), a hormone that is secreted mainly by the paraventricular nucleus of the hypothalamus (Manteca 2008). It is reported that the response to stress is represented by sympathetic nervous system release catecholamines epinephrine and norepinephrine which is acting fast and HPA release glucocorticoids (cortisol and Corticosterone) acted low (5"Verbrugghe et al., 2012) and carried by the blood to all cells of the body(2"Siegel and Gross, 2000) . 1"Balm (1999) reported that glucocorticosteroids and catecholamines provide defense on the front lines of mammalian when they exposed to stress.
In 2000, 2"Moberg and Mench demonstrated the metabolic consequences of stress. The authors reported that the stress has altered an animal's metabolic. He indicated that animal response to stress because of the endocrine system. 2"Moberg and Mench (2000) indicated that the hypothalamic -pituitary neuroendocrine system secreted hormones regulated the biological functions such as metabolism and behavior when the animals exposed to stress. They demonstrated that the secretion of hormones under stress caused alteration metabolism and behavior. Adipose tissue and endocrine regulat appetite and feed intake (2"Moberg and Mench 2000). It is regulated through the elaboration of adipocyte factors like leptin, which can interact with specific receptors for leptin in the hypothalamus in nuclei traditionally identified as feeding and satiety centres. Appetite is often depressed during infectious disease challenges.
The Metabolism of ruminants is reduced when they influenced to heat stress. This finding is linked to with the thyroid secretion and gut motility decreased result in an increase in gut fill (Nissim Silanikove 1992).
Restriction of food and water is likely to accumulate stress. The welfare is reduced when the gastrointestinal tract progressively is empty and also the immune system might be suppression because of restraction of food and water however, this has not been evaluated (Phillips, 2008).
The relationship between metabolic and dehydration measurements of animal while they are transported have been investigated. The finding of study conducted by 3"Fisher et al., 2010 about transport a 38 kg sheep by truck for 3, 9, 15, 18, or 24 h, found that the sheep were not clinically dehydrated or metabolically compromised. they indicated that metabolic and dehydration status of sheep transportation stayed within acceptable limit. The finding also found that the sheep behavioral had adapted to the journey environment in nine hours after commencement. 3"Fisher et al., 2010 reported in the literature that this finding is similar to the findings of study conducted by Knowles et al. in 1994 about transport of 36-kg sheep transported for 18 and 24 h.
Cole (2000) indicated that after these feeder cattle arrived at a feedyard they had low feed intake by for 1 to 3 weeks. The author reviewed that some reporters suggested that the cause of the low feed intake is because of the involving of the reduction of ruminal fermentative activity and metabolic patterns.
It has been reviewed the effect of temperature on the digestibility in ruminants (2"Christopherson 1983). The authors indicated that when ruminants esxposed to low temperature in the digestibility of certain diets Decrease due to changes in the rate of passage of digesta through the gastrointestinal tract. The rates of passage of digesta in the gastrointestinal tract is increase which reflect rumination activity. This changes is opposite the digestive parameters response to heat stress. When ruminants exposed to high temeperture the Rate of passage of digesta in the gastrointestinal tract is low which lead to reduce the redued ruminal activity and rumen motility (Nissim Silanikove 1992).