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ThesisItem Open Access Influence of particle size of feed and plane of feeding on growth,physiological reactions and carcass characteristics of growing-finishing pigs(Department of Livestock and Production Management, College of Veterinary and Animal sciences, Hissar, 1981) Kurien, Thomas; KAU; Singh, R AThirtysix Large White Yorkshire barrows averaging 70 days of age and 11.2 kg weight were assigned at random to six dietary treatments in order to study the influence of feed particle size and level of digestible energy on the performance, physiological reactions and carcass characteristics. They were individually housed and maintained on diets compounded mainly of dried sardines, dried tapioca, groundnut cake and rice bran till they were 8 months of age. The barrows were provided with the experimental diets having 100%, 90% or 85% of NRC standards of DE with feed particle size of less than one or two to three millimeter. It was observed that variations in feed particle size did not produce any significant effect on growth, physiological reactions and carcass characteristics of pigs under any of the treatments. At 8 months of age, the pigs under treatments 1 and 4 (100% DE of NRC; 2 and 5 (90% DE of NRC) and 3 and 6 (85% DE of NRC) had, (i) a final weight of 102.9; 99.4; 86.8; 92.3; 67.1 and 67.2; (ii) an average daily gain of 0.545; 0.524; 0.448; 0.473; 0.329 and 0.326 kg, and (iii) feed conversion ratio of 3.4; 3.5; 4.3; 4.2; 5.6 and 5.4, respectively. The pigs under treatments 1 and 4 reached 70 kg weight at an age of 197.5 days on an average, while pigs under treatments 2 and 5 reached the same weight by 208.5 days, and under 3 and 6 by 228 days. The digestibility of dry matter, organic matter, ether extract and crude carbohydrate in pigs under all the treatments was significantly (p <0.01) lower with decreasing levels of DE at 5 and 7 months of age. Although the digestibility of crude protein was significantly higher (p <0.01) in pigs that received 100% DE of NRC than 85% at 5 and 7 months of age, it was statistically of the same order with that of 90% at 5 months of age. Dietary treatments had no significant effect on the rectal temperature, heart rate, respiration rate and haemoglobin concentration of blood of the experimental pigs. The yield of dressed carcass was decreased from 72.3% to 68.8% or 64.7% with the decreasing body weight of pigs on 100%, 90% or 85% DE of NRC standards, respectively. The yield of ham was increased from 21.3% to 22.5% or 23.5% with the decreasing levels of DE, respectively. The length of carcass, eye muscle area and overall backfat thickness were significantly (p <0.01) lower as the level of DE was decreased. The fat percentage in dried eye muscle was almost uniform (22.3 to 24.9%) in pigs under different dietary treatments. The quality score for marbling, colour and firmness was significantly (p <0.01) in favour of diets that contained higher of DE. The feed cost per kg body weight gain of pigs under different dietary treatments or total cost of feed and labour at market weight of 70, 80 and 90 kg were determined. The cost of raising pigs from weaning to these weights on rations containing 90% DE of NRC standards and two to three millimeter feed particle size was found to be most economic. An equation W = 5.16 + LG2/11568 was evolved predicting live weight of barrows ranging from 8 to 144 kg, where W, is the weight in kg, L, is the length of body in cm, and G, is the girth in cm.ThesisItem Open Access Effect of environmental heat stress on performance of crossbred dairy cattle(Department of Livestock Production Management, College of Veterinary and Animal Sciences, Mannuthy, 1989) Thiagarajan, M; KAU; Thomas, C KAmple evidences are available on the poor performance of livestock inhabiting the tropical regions of the world, compared to their counterparts in the temperate zones. By and large, the management practises adapted in the warmer areas are to be quite different from cooler regions to reach optimum productivity. Among the management practises, housing and feeding aspect needs to be given more emphasis in bringing about the much desired results to meet the ever increasing demand for livestock products. In the present work, an attempt has been made to investigate the effects of housing and feeding inter alia. On the growth and production of B. Taurus x B. indicus crossbred cattle. Besides these, some of the important climatic components, such as solar radiation, mean radiation, temperature of the surrounding and the wind velocity, the factors which have hither to been widely neglected, were tried to be methodically quantified and presented in relation to their direct effect on the physiological and productive responses of cattle. To assess the effect of shelter and the type of ration on the physiological responses and growth performance of crossbred cattle, an experiment involving 20 weaned heifer calves, was conducted at the University Livestock Farm (KAU), Mannuthy. The experiment included four treatments encompassing protection and exposure to solar radiation, and concentrate and roughage – oriented feeding in different combinations. The selected calves were distributed equally to the four treatments, observing the standard statistical procedures. Physiological variables like cardiac rate, respiration rate, rectal temperature and skin temperature were measured and recorded for all the calves twice a day on a fixed day in a week and for 14 weeks of the study by using standard equipments and procedures. The body weights and body measurements were recorded once in a fortnight at a fixed time in a day. The body measurements included height, length and girth. All the measurements were made on individual calves. The climatic data, atmospheric temperature, relative humidity, wind velocity, black globe temperature and vapour pressure were recorded inside the shed and atmospheric temperature, solar radiation, relative humidity, wind velocity, vapour pressure and rainfall were recorded in the open paddock. A continuous recording “Solar Radiation Balance Meter” was used to record the solar radiation continuously throughout the experiment. The average daily maximum air temperature that prevailed in the unshaded location during the hot – dry period was 350 C and in the shaded location, 300 C. During the rainy period the maximum temperature ranged from 25.37 to 29.310 C under the shade and 29.36 to 33.500 C in the unshaded location. The relative humidity ranged from 76 to 93 per cent in the mornings and 55 to 88 per cent in the afternoons. The wind velocity ranged from 0.13 to 0.97 m per sec in the unshaded area and almost zero in the shaded area. The vapour pressure ranged from 21.41 to 25.98 mm of Hg. The rectal temperature of the calves in the unshaded location was significantly higher than those of the shaded ones (P < 0.01) during the hot – dry period. Significantly lower value for rectal temperature was obtained for the concentrate – fed unshaded calves during the morning recording of rainy period and higher values were obtained in the afternoons indicating a diurnal rhythm. The skin temperature of the calves was always higher than the rectal temperature in all the cases except in the shaded calves on rainy days. During the hot – dry period, the respiration rates were significantly higher (P < 0.01) in the unshaded group compared to the shaded lot for the morning recordings and in the afternoons, in all the treatments, it was almost double of what was recorded in the mornings. In general, the cardiac rates were found to be higher in the afternoons, than the mornings and lower during the rainy period. Highly significant variations (P < 0.01) in all the physiological reactions measured were noticed between the housed and unhoused treatments, the calves exposed to direct solar radiation recording higher values of rectal and skin temperature and respiration and cardiac rates, with few exceptions. The higher physiological reactions of the calves in the open could be attributed to higher effective temperature caused by direct solar radiation. The analysis of growth parameters indicated significant differences in certain fortnights only. It was observed that maximum gains in live weight, height and girth were obtained by the calves exposed to solar radiation and fed roughage – oriented ration but the gain in length was the least in this group. The next best was the housed and concentrate oriented feeding group which had the highest gain in length, second highest gains in live weight and girth, but the lowest gain in height which implies that under housed conditions concentrate – oriented feeding and under exposed conditions roughage – oriented feeding favour better growth. In general, it was observed that housing in open conditions increased physiological reactions significantly but these increases were not physiologically meaningful to cause retardation in growth. With a view to study the effects of housing on cows with respect to milk production and other traits, eight cows were subjected to a switch over trial in which sheltered and unsheltered conditions alternated. The experiment ran for eight periods of one month each and in total, milk production for 33 weeks were partitioned into 15 weeks of early lactation and the remaining 18 weeks of late lactation periods. The cows were divided into two groups based on their milk yield. The cows of one of the groups at random were kept in an open paddock exposed to direct solar radiation while cows of the other group were housed in a tile – roofed shed. At the end of every month the groups were interchanged. For feeding the cows, adequate measures were taken to meet both maintenance and production requirement and requirements were worked out every fortnight. The physiological variables like the cardiac rate, respiration rate, rectal temperature and skin temperature of the individual cows were measured and recorded twice in a day, two days in a week, by following standard procedures. The twice daily milk yields of the cows were measured by individually weighing the quantity in kg at each milking. Milk fat and protein were estimated from samples collected with due precautions at every milking. The feed, grass and water consumption were measured for individual cows. Standard statistical methods were employed to analyse the data. Multiple regression analysis was resorted to find out the relationship of climatic variables with physiological responses. Highly significant (P < 0.01) differences were found between the shaded and unshaded locations in the relative humidity levels. This may probably be due to accumulation of moisture in the atmosphere inside the animal house resulting out of interference with free exchange of air by housing arrangements. Analysis also revealed highly significant (P < 0.01) difference in wind velocities between locations. The wind velocities recorded in the present experiment generally were lower than what had been suggested as ideal for tropical animal husbandry. The analysis of climatic factors revealed that the animals housed in the shaded location were under additional stress due to radiated heat from the surroundings apart from experiencing stress of the high air temperature. The same phenomenon was observed in the unshaded location also. Both the day and night total radiation values remained high. The rainfall distribution was not uniform during the period of study. In the early lactation period, the cardiac rates, respiration rates, rectal temperature and skin temperature of cows under exposed condition were high in the afternoons. Similar trend was observed in the late lactation period also. In both the treatment groups, all the physiological parameters recorded were on the higher side than the normally accepted standards. The cows had the physiological ability to bring the skin temperature on par with rectal temperature and sometimes even higher than that. The cows in the open seem to compensate during the night and bring down their body temperature to the level of sheltered and eat as much or more of grass and feed. This resulted in similar milk yield in late lactation and slightly higher milk yield in early lactation. Under the hot humid conditions, the higher wind velocity in the open seem to favour the cows considerably. The generally held view that under hot humid conditions ventilation is most important and animals do not need much elaborate housing gets further strengthened from these findings. It was observed that the fat percentages varied significantly (P <0.01) between treatments from both morning and afternoon milk obtained from the cows, the milk fat content being lower when they were exposed to direct solar radiation. The exposed cows though they had maintained their milk production higher, the milk fat content had dropped. A highly significant (P < 0.01) difference had been found between treatments in protein content of the afternoon milk indicating that exposure of cows to day time stress in the open sun considerably altered milk composition and reduced the protein percentage. During late lactation period, both fat and protein content in milk were lesser for the unshaded treatment but statistically there was no significant difference between treatments. A highly (P < 0.01) significant difference was observed in concentrate feed intake between shaded and unshaded treatments during early lactation and the reverse was observed in the case of grass consumption. The difference in overall mean water consumption under shaded and unshaded condition was highly (P < 0.01) significant, cows remaining in the open paddock drinking 21 to 23 per cent more water. Observations on physiological reactions revealed that the cows in the unsheltered condition made physiological compensations through increased circulatory and respiratory activities and by physical means during the night to bring down the rectal temperature in the morning to normal levels. During the late lactation period, no significant differences were found in the consumption of grass and concentrate feed by the cows between treatments. A highly significant difference (P < 0.01) was found only with water consumption. During the early lactation, the solar radiation was found to exert a negative, significant (P < 0.05) influence on the cardiac rates but the influence by wind velocity was positive and highly significant (P < 0.01). In the same way, the rectal and skin temperatures also were influenced significantly only by the wind velocity, the effect being negative and highly significant (P < 0.01). During the late lactation stage, the physiological parameters studied had not been influenced by the explanatory variables chosen except in the case of respiration rate which was positively and significantly (P < 0.05) influenced by black globe temperatures. The relationships between climatic variables and animal responses were not as intense when they were housed as when they remained exposed. However, the black globe thermometer readings which represented the combined influence of ambient temperature, wind speed and solar radiation, was found to have significant influence on the respiration rate. This may indicate that the black globe thermometer deserves to be used more extensively for evaluating thermal characters of animal environments. The results of the study clearly indicate the beneficial effects of ‘open – air’ conditions in a hot – humid tropical environment. Factors such as comfort of men tending animals and hygiene preclude cattle keeping without housing structures. The result of these experiments however point to the advisability of loose housing system in which cattle have continuous access to an open paddock shaded by trees. The sheltered area of the loose houses also should be simple roofs on pillars allowing maximum ventilation and air movement. It was also found that growing heifers can be maintained equally well on a roughage – oriented feeding schedule.ThesisItem Open Access Factors influencing calf growth and mortality in field and organised farms(Department of Livestock Production Management, College of Veterinary and Animal Sciences, Mannuthy, 1994) Shaji, Antony .; KAU; Thomas, C KA study was undertaken to evaluate the system of calf raising in the field vis – a – vis that in organised farms, which included contemporary calves born in field and organised farms. Mavelikkara was chosen as the study area from where the experimental field calves were selected. University Livestock Farm, Kerala Agricultural and Dhoni Farm, KLD Board, Palghat were chosen to represent organised farms in the experiment. All the calves born in the experimental area or farms during a period of two months were included in the experiment. Calves were studied upto period of six months of age. It was observed that climatic conditions in general were similar at the three locations except that at ULF, Mannuthy relative humidity and hours of bright sunshine tended to be less than the other two locations. The male calves in the farms weighed heavier at birth and gained faster to weigh significantly more at the 12th fortnight compared to those in the field. There was no significant difference in birth weight of farm and field born female calves. However, those in the farms grew faster to weigh significantly heavier at 12th fortnight. When male and female calves in the farms and field were put together and tested at 1st, 6th and 12th fortnights, the calves in the farms weighed significantly heavier than those in the field at all stages. The daily weight gain during different fortnights was higher in the farm grown calves compared to their counterparts in the field. There was no significant difference in height of male calves in the farm and field in the 1st fortnight but was significantly higher in the farm grown calves in the 6th and 12th fortnights. There was no significant difference in the height of the female calves in the farms and field in all the three fortnights tested. Information with respect to girth showed similar trend as in the case of weight and height. In the first fortnight, the male calves in the farms measured significantly shorter in length than those in the field but by 6th and 12th fortnights, they measured significantly longer than male calves in the field. There was no significant difference in length of female calves in the field and farms during the time intervals tested. In the field, calves received generally an adequate amount of colostrum through suckling. Those in the farm were fed 2 – 2.5 kg colostrum daily from the pail. The interval between birth and first nursing varied from 15 min to 2 h in the field. In the farms, calves born during day time received colostrum within half an hour, while those born in night received colostrum the next morning. Highest daily gain and lowest mortality was seen in calves fed colostrum within 15 minutes. It was observed that the quantity of milk available to female calves in the field was comparable to that in the farms. Male calves in the field received much lesser quantity. Female calves received more quantity of concentrates compared to males except in the early fortnights. Maximum daily gain of calves was observed in sheds with concrete flooring and tiled roofs. Monthly deworming was practised upto 12 months of age in the two farms studied. In the field all calves were dewormed during the 1st month only. Thereafter, female calves were given more frequent deworming treatment. Vaccination against Foot and Mouth disease was carried out in the farms but not in the field. Good hygiene and daily grooming increased the daily gain of calves. Better growth was seen when the animals were looked after by men than women. Average dairy awareness was observed in 90 per cent of the farmers. Daily gain of calves increased with increased dairy awareness. People with high school level education maintained their calves better than those with higher or lower levels of education. Calves grown by agricultural labourers seemed to have lower weight gain. Calves reared in larger units of land had a greater daily weight gain. The mortality rate among calves was 14 per cent in the field compared to 8.5 per cent in the farms. Mortality rate of 66.6 per cent was seen no colostrum was fed. There was no mortality among calves fed colostrum within 15 minutes. Male calves had higher mortality rate than female calves. Higher mortality rate was observed in calves born to first calvers. In field mortality was higher in 1st and 5th month of age. Mortality rate was lower when calves were looked after by men compared to women. The lowest calf mortality rate was observed among calves owned by those who had high school level education. Mortality rate among calves seemed to decrease with increasing dairy awareness of owners. Mortality rate of calves was highest in shed and premises with poor hygiene (50%) followed by medium hygiene (11.11%) and good hygiene (10.5%). Similarly daily grooming seemed to reduces mortality rate (11.9%) compared to weekly grooming (25%). At the end of 6 months, 92.85 per cent of the female calves were retained by the farmers compared to only 36.36 per cent male calves, clearly pointing towards the greater future economic utility of the former.ThesisItem Open Access Comparative draught capacity of cattle and buffaloes(Department of Livestock Production Management, College of Veterinary and Animal Sciences, Mannuthy, 1994) Anil, K S; KAU; Thomas, C KThe draught performance of Kangayam bullocks were compared with that of graded Surti buffaloe bullocks under the agro climatic conditions of Kerala with a hot humid tropical climate Two pairs of adult Kangayam bullocks and two pairs of adult graded Surti buffaloe bullocks were used for ploughing both dry land and wet land at the rate of four hours a day during the summer season Physiological responses like respiratory rate pulse rate and rectal temperature and haemotological parameters like haemoglobin per cent erythrocyte sedimentation rate packed cell volume lactic acid and plasma bicarbonate were estimated before work immediately after work and after one hour of rest after work The dry matter intake and water intake on days of work and on days of no work were also measured and compared Other parameters like the area ploughed in one hour average speed of walking stride length and traction force developed during ploughing were also compared between the two species The buffaloe bullocks had significantly lower physiological responses before the start of work when compared to that of indigenous bullocks As a result of work the physiological responses increased significantly in both species The values were higher for buffaloes during dry ploughing The physiological responses including rectal temperature of buffaloes increased to a level indicative of distress due to heat stress There were also other signs of distress like frothing and drooling of saliva and protrusion of tongue But during wet ploughing the responses were not so marked in case of buffaloes and they did not show any apparent signs of distress The physiological responses decreased but did not reach the pre-exercise values after one hour of rest The haemoglobin per cent of blood packed cell volume and plasma bicarbonate content decreased significantly in cattle and buffaloes during dry and wet ploughing The erythrocyte sedimentation rate and blood lactic acid content showed a significant increase as a result of work One hour of rest was not sufficient to bring these parameters to pre exercise values Buffaloes consumed more DM when expressed in grams per kg metabolic body size Both species consumed more on days of no work The difference was more pronounced in case of buffaloes The water intake expressed as ml/kg metabolic body size was significantly higher for buffaloes both on days of work and on days of no work In both the species the water intake remained similar in days on which they were used for work and they were not used Kangayam bullocks ploughed significantly more area per unit time than graded Surti buffaloe bullock Cattle developed significantly more speed than buffaloes during dry ploughing But during wet ploughing the speed was almost same in both species Cattle showed more stride length during dry and wet ploughings than buffaloes But during wet ploughing the difference was negligible There was no significant difference in the traction power developed between cattle and buffaloes during dry or wet ploughings But both species developed higher horse power during wet ploughing Overall the results indicate that during summer in a hot humid tropical environment Kangayam bullocks can be used for dry as well as wet ploughings without any apparent ill effects Graded Surti buffaloe bullocks are on par with Kangayam bullocks under wet-ploughing However they seem to be under severe heat stress and also their work output inferior when used for a continuous 4 hour period of dry-land ploughing under similar climatic conditionsThesisItem Open Access Managemental effects of synchronization of oestrus in goats(Department of Livestock Production Management, College of Veterinary and Animal Sciences, Mannuthy, 1993) Shivkumar, S; KAU; Thomas, C KAn experiment was conducted to study the managemental effects of synchronization of oestrus in goats using parentral administration of PGF2 alpha, on a flock of Malabari, Malabari x Saanen and Malabari x Alpine goats maintained at the Agricultural University Goat Farm, Mannuthy. Forty cyclic goats were selected in pairs on the basis of similarity in genetic group, body weight and age. The does from each pair were allotted to two groups at random. Out of these one group at random formed the treatment group and the other control. The goats in the treatment group were given two injections of 10 mg (I/M) each of PGF2 alpha separated by 11 days, in two batches of 10 goats each. The animals were mated at the synchronized oestrus following the second PG injection. The does in the control group were mated as and when they came to oestrus. Heat detection in the does was carried out by parading the vasectomised bucks twice daily and by observing the behavioural manifestations of oestrus. The results and conclusions of the study are given below. The PGF2 alpha treated goats showed 75 and 100 per cent oestrus synchrony after a mean interval of 45.93+2.19h and 48.38+2.06 h following the. first and second injection of PGF2 alpha respectively. Of the various signs of oestrus only rapid waving of tail in the presence of male and vaginal mucous discharge were observed in all the does in oestrus. Various signs of oestrus behaviour including receptivity was found to be more pronounced in oestrus synchronized does using PGF2 alpha than in the controls. Mated does showed pricking of ear and arching of back as post coital reactions. Conception rate following mating at the first oestrus was better in the treatment group (85%) than the controls (75%). Body weight changes during pregnancy was not found to be affected by synchronization of oestrus with prostaglandin F2alpha. Mean gestation period in the treatment group was ,148.14+0.80 days compared to 143.88+0.78 days in the controls, the difference being significant (P < 0.05). Overall 61.3 per cent of the parturitions were observed to occur between 0600 to 1800 hours. Maternal behaviour studies showed no significant difference between the does in the control (av. score 3) and treatment group (av. Score 2.8). Multiparas were observed to possess better maternal Instinct than the primipara does. The new born kids attempted to stand up within 8 to 15 minutes and 68 per cent of them suckled from the dam's teat within one hour of birth. In the control group 88 per cent of the kiddings were singles and 11.77 per cent twins compared to 85.71 per cent singles and 14.29 per cent twins in the treatment group. Comparing the growth of kids with respect to body weights and body measurements at fortnightly intervals from birth to 90 days of age, showed that the growth rate of kids born from synchronized oestrus was similar to that of control kids. Suckling behaviour in the kids revealed that the overall mean duration of suckling was 2.61 minutes and mean rate of suckling was 49.65 g per minute. It was observed that the rate of butting and intensity of tail wagging increased as the flow of milk from the teats got reduced. The mean daily milk yield from first to thirteenth week of lactation in the control and treatment g roups were found to be 0.509+0.015 kg and 0.493+0.014 kg respectively. Man nours requirements to look after the does and raising the kids born to tham to 90 days of age in both the control and treatment group, revealed that there was a man hour saving of 12.3 per cent in the oestrus synchronized group (treatment) than the untreated controls.ThesisItem Open Access Evaluation of the feeding value of tea waste for milk production in cows(Department of Dairy Science, College of Veterinary and Animal Sciences, Mannuthy, 1978) Prasad, V; KAU; Subramanyam, MAn investigation was carried out to find out the feeding value of tea waste for milk production in cows. A total of nine Jersey x Sindhi crossbred cows were divided into three groups of three animals each and fed tea waste in their concentrate ration at 0, 15 and 25 per cent levels. A switch – over design was used for the experiment.ThesisItem Open Access Effects of weight at weaning and plane of feeding on the onset of puberty in gilts(Department of Livestock Production Management, College of Veterinary and Animal Sciences, Mannuthy, 1993) Lalnuntluangi, Hmar; KAU; Rajagopalan, T GThirty six Large White Yorkshire weanling females of 8 kg (light weaners) and 12 kg (heavy weaners) were randomly maintained on three different planes of feeding with respect to crude protein (CP) and digestible energy (DE) viz. (i) NRC recommended levels as control, (ii) a high plane (HP) of 10 per cent increase of CP and DE with respect to NRC level and (iii) a low plane (LP) of 10 per cent decrease of CP and DE with respect to Nrc from weaning to puberty. The fortnightly and daily weight gain was higher in pigs fed NRC diet. The heavy weaners were having a better growth rate, daily gain, higher feed intake and attained puberty earlier than the light weaners, but the feed conversion efficiency was lower than light weaners. The heavy weaners on high plane attained puberty earlier than animals on NRC or low plane diet. In light weaners, NRC group attained puberty earlier than HP and LP group. In both heavy and light weaners, LP group attained puberty later than the other treatment groups. Plane of feeding has no significant effect on puberty attainment, oestrous cycle length and duration of pubertal cestrus but weight at weaning has a significant effect on the onset of puberty. Oestrous hehaviour expressed as scores was significantly affected by plane of feeding. The animals on high plane diet consumed less feed in both heavy and light weaners and have the highest feed conversion efficiency. The light weaners consumed feed comparatively lower and have better feed conversion efficiency than heavy weaners. The overall result suggested that heavy weaners on high plane diet are most efficient in feed conversion efficiency, economy and attainment of puberty at younger age. On the whole, the heavy weaners are more economical for replacement stock than light weaners.ThesisItem Open Access Influence of chitin on growth and fatty acid composition in growing pigs(Department of Livestock Production Management, College of Veterinary and Animal Sciences, Mannuthy, 1993) Chitta Ranjan, Pradhan; KAU; Rajagopalan, T GA study was carried out to find out the influence of feeding chitin to pigs on their growth, carcass characteristics, blood cell count and haemoglobin concentration, serum cholesterol and triglyceride levels, and fatty acid profile of muscle and backfat. Twenty-four weaned female piglings of Large White Yorkshire breed were assigned to three groups of eight each. Two groups were fed chitin with a standard farm ration at levels of 0.5 per cent (Group I) and I per cent (Group 2), and the remaining group, which served as the control, was fed only the ration without addition of chitin (Group 3). All animals were housed individually and were fed in two I-hour feeding periods daily. Digestibility of chitin did not differ between the two chitin-fed groups. The percentage of digestibility increased from age 3 months (79.37 ± 1.85 to 80.49 ± 1.85) to 5 months (95.36 ± 1.13 to 96.54 ± 1.05) and thereafter remained constant at 7 months (95.35 ± 1.33 to 95.77 ± 1.57). The chitin-fed groups had significantly (P<0.05 or 0.01) higher body weights than the controls from 18th to 40th week of age. Compared with the controls, the chitin-fed groups had higher total gains in weight by 11 to 12 kg. Both the chitin-fed groups also had significantly (p<0.05 or 0.01) higher average daily gains than the controls from 18th to 40th week of age. The pigs in all groups showed a peak rate of gain at 32nd week of age. The chitin-fed groups also averaged higher body lengths, heights and girths, and also higher daily gains in these measures as compared with the control group. Daily feed intake increased with age of animals in all the groups. Daily feed intake did not differ significantly between the groups. For all the groups, maximum feed efficiency was recorded between 16th and 30th week of age. As compared with the controls, the chitin-fed groups showed higher feed efficiency. The difference between the control and chitin-fed groups were found to be significant (P<0.05) at the end of the experiment. The pigs in the chitin-fed groups averaged higher slaughter weights than the controls at 5, 7 and 9 months of age. For all the pigs in all groups, carcass length, ham weight and eye-muscle area showed higher percentages of gain between 5 and 7 months than between 7 and 9 months of age. The percentage of ham decreased with increase in age and weight of animals. The chitin-fed groups of pigs showed higher carcass lengths, ham weights and eye-muscle areas than the control group at each stage of slaughter. The backfat deposition showed a higher deposition between 5 and 7 months than between 7 and 9 months of age, while the majority of leaf fat deposition took place between 7 and 9 months of age. The percentage of leaf fat increased with increase in age and weight of animals in all the groups. The chitin-fed groups showed lower backfat thickness and lower percentages of leaf fat than the controls at each stage of slaughter. The increase in dressing percentage was found to be higher between 7 and 9 months than between 5 and 7 months of age, for all groups of pigs. The chitin-fed groups yielded higher dressing percentages than the control group at each stage of slaughter. The weight of internal organs increased with age of animals, whereas weight of internal organs as percentage of live weight decreased. The control group of pigs had higher percentages of internal organs than the chitin-fed groups at each slaughter age. The haemoglobin concentration, total erythrocyte count, total leukocyte count, and differential leukocyte count did not differ significantly between the groups of pigs at 5, 7 or 9 months of age. The pigs in group 2 averaged the lowest serum cholesterol and triglyceride levels followed by the pigs in group I and group 3, in that order, at 5,7 and 9 months of age. The difference in serum cholesterol concentration between the pigs in group 2 and the pigs in either group 1 or group 3 were found to be significant (p<0.05) at 7 months and highly significant (p<0.01) at 9 months of age. The serum triglyceride concentration followed the same trend as serum cholesterol concentration, between the groups of pigs. However, the differences were not found to be statistically significant. The fatty acid composition of muscle and backfat did not differ noticeably between the groups at 5 months of age. At the subsequent ages of 7 and 9 months, the chitin-fed groups showed markedly higher degree of unsaturation and lower saturation than the control group. Higher percentages of oleic acid and lower percentages of palmitic acid were recorded for the chitin-fed groups as compared with the control group. The results revealed that chitin had growth-promoting, hypolipidemic and hypocholesterolemic effect in pigs. It also improved the degree of unsaturation in pig meat.ThesisItem Open Access Draught potentialities of indigenous and cross-bred cattle(Department of Livestock Production Management, College of Veterinary and Animal Sciences, Mannuthy, 1988) Sreekumar, D; KAU; Thomas, C KThe draught performance of Bos indicus x Bos Taurus crossbred bullocks was compared with that of bullocks belonging to a South Indian draught breed (Kangayam type) under the agro - climatic conditions of Kerala, with a hot – humid tropical climate. Two pairs of adult cross – bred bullocks (Jersey x Red Sindhi) and two pairs of adult indigenous bullocks (Kangayam type) were used for ploughing on dry land for 4 hours and 5 hours continuously on alternate days. Physiological responses like respiratory rate, pulse rate and rectal temperature and haematological parameters like haemoglobin per cent, erythrocyte sedimentation rate, packed cell volume, lactic acid and plasma bicarbonate were estimated before work, immediately after work and after 1 hour of rest after work. The dry matter intake and water intake on days of work and on days on which no work was done were measured and compared. In order to evaluate the relative efficiency of work, the average speed of walking and the total area ploughed in 1 hour were compared. The cross – bred bullocks had significantly higher physiological responses even before the start of work. As a result of work the physiological responses increased significantly and during rest, the values declined but did not reach the pre – exercise values after one hour rest. The haemoglobin per cent of blood, packed cell volume and plasma bicarbonate content decreased significantly and the erythrocyte sedimentation rate and blood lactic acid content showed a significant increase as a result of work. One hour of rest was not sufficient to bring these parameters to pre – exercise values. The indigenous bullocks consumed more dry matter per metabolic body size than the cross – breds. However, the total dry matter intake by the indigenous bullocks was less due to smaller body size. It was found that work had no effect on dry matter intake as the dry matter intake of indigenous and cross – bred bullocks on days of work and on days on which no work was done was almost similar. The cross – breds consumed more water per day matter per metabolic body size on days of work and no work. The total area ploughed by indigenous bullocks in 1 hour was significantly more than the cross – bred bullocks. Also, the average speed of walking of indigenous bullocks was greater than that of the cross – breds. The enhanced physiological reactions in the cross – breds even before the work pointed to the fact that they were under some degree of thermal stress due to the hot – humid climate. Exercise (work) increased the stress and widened the gap between the cross – breds and indigenous bullocks. The lower total feed intake and greater speed and more area ploughed per unit time make the indigenous Kangayam type bullocks a more economical animal. Their higher feed intake and lower water intake per unit metabolic size indicates that they can better sustain energy supply to the tissues for work and manage under lower water availability. Coupled with these advantages, their greater heat adaptability make them a superior draught animal.