Master Thesis      [Total: 109 ]

studies o using spirulina for fingerlings Nile tilapia diets

Ayman Hussien Abo elward, 2016


The experiments were conducted in Fish Research Center - Suez Canal University: The present study was designed to evaluate the use of spirulina (Spirulina platens is) as a replacement of protein with different levels from protein diet for fingerlings Nile tilapia (Oreochromis niloticus). Spirulina was incorporated into tive isonitrogenous and isocaloric diets
At 0, 5, 10, 15 and 20% of the protein - based diet. The test diets were fed to the fishat satiation twice a day for 56 days. The final weight gain, specific growth rate, feed conversion ratio, feed efficiency, feed intake, protein efficiency ratio and survival rate of fish significantly (p<0.05) higher for group of fish replaced with 20% Spirulina platensis (T5) and decreased gradually at T4 ,T3,T2 and Tl respectively. There was a significant difference in protein and lipid in carcass proximate composition of the fish fed on 20% spirulina diets as compared to those on the rest of experimental groups. These results suggest an improvement of fish health when fed with feed replacement, Moreover, fish fed with diets containing different spirulina levels exhibited higher total protein serum Creatinine, Urea, Albumin, Globulin, Triglycerides, HDL-C values. On contrary, significantly decreased Albumin Iglobulin Ratio, LDL-C, AL T and AST values compared with control as increased of Spirulina levels. The highest values were obtained at T5 diet.
This study demonstrates that up to 20% of spirulina replacement from soybean protein was most effective in stimulating fish growth and more economic for Nile tilapia (Oreochromis niloticus) fingerlings under this experimental condition.
Key Words Spirulina platensis, replacement, Nile Tilapia fingerlings, growth performance, feed utilization, carcass composition.

Genetic Studies on Growth Hormone as A Physiologgical Indicator in Rabbits

Sara AbdEl-Ghany, 2015


The aim of the present study was to evaluate the effects of GH gene polymorphisms on reproduction and growth traits and identify its variability in the rabbits.
A total of 218 blood samples collected from rabbits were used to evaluate the allele frequency distribution for GH gene polymorphisms and its association with reproductive and growth traits in rabbits. The samples included 16 rabbits of the different breeds (Middle-Egypt native breed, Gabali Sinai, Baladi Black, Baladi Red and New Zealand White) and 202 rabbits (118 female and 84 male) from APRI rabbits. The traits tested were: (1) body weight (BW) at 5, 6, 8,10 and 12 weeks from birth, (2) daily bodyweight gain (DBG), (3) reproductive traits included age at puberty (AP), Kindling interval (KI), litter size at birth (LS), litter weight (LW) at birth, Litter size at weaning (LSW) and litter weaning (LWW), (4) milk yield. For this purpose, DNA was extracted from rabbit blood samples and used in PCR amplification. The c.-78C >T SNP was genotyped by PCR-RFLP using the digestion by restriction enzyme Bsh1236I (BstUI).
Association analysis between the GH C >T SNP and body weight, growth and reproductive traits was tested in the rabbits population using SAS program. The heterozygous genotype was associated with heavy weight of rabbits in different ages during the growth period. This increase in weight was significant (P < 0.05) at 8 weeks of age. DBG through 5-8 week interval was significantly associated (P < 0.05) with the T/C genotype. The heterozygous genotype (T/C) exhibited higher values in the DG compared to C/C and T/T genotypes. The estimated dominant genetic effect (d) was significant (P < 0.05) in 8 weeks. The C/C genotype showed significant value (P<0.05) associated with early age of puberty. The estimated additive genetic effect (a) and estimated dominant genetic effect (d) in a population was insignificantly associated (P<0.05) within all the investigated reproductive traits in rabbits. Polymorphism of heterozygous genotype T/C was associated with milk yield traits of rabbits during the first two weeks in suckling period. Estimated additive genetic effect (a) in a population was significant (P<0.05) within milk yield at the second week of suckling period of rabbits. Estimated dominant genetic effect (d) was significant (P < 0.05) within milk yield at the first week of suckling period of rabbits. In conclusion, the polymorphism of growth hormone (GH) gene in rabbits may has over dominance at the locus c.-78C >T. Positive effects of the heterozygous genotype were recorded compared to both homozygous genotypes on body weight, body gain and milk yield at the first two week. The effect of the C allele of GH gene decreased the age of puberty in rabbits.
Effects of the heterozygous genotype in c.-78C > T of GH polymorphisms on the tested traits in current study and on the fmishing weight in previous study could be selected as a favorable genotype in rabbits and may be used in Marker-assisted selection (MAS) programs to improve growth performances rabbits.
Key words: Rabbit, GH , association study SNP , reproductive, growth traits.

Reducing Antibiotics and Drugs in Broiler Chicas by using Egg yolk AntibodiesReducing Antibiotics and Drugs in Broiler Chicas by using Egg yolk AntibodiesReducing Antibiotics and Drugs in Broiler Chicas by using Egg yolk Antibodies

Fatma Saad Mohamed, 2014


The experiment was designed to evaluate the use of antibiotics Alternatives and some vaccination programs by using hyperimmunized egg yolk in broiler chicks. 500 one day old Hubbard and cobb broiler chicks were used. They were divided into four groups; the first group is the control one, the second group was injected egg yolk containing immunoglobulin which type (Ig) against (NDV), IBDV and alternative antimicrobial agents to poultry production and processing. Bacteriocins are proteinaceous compounds of bacterial origin that are lethal to bacteria other than the producing strain within tow strain of broilers. The present results showed that the broiler chicks injected egg yolk containing immunoglobulin against IBDV, NDV and combination recorded the highest hemoglobin and hematocrit level compared to control group. Similar trend was noticed for white blood cells count.
However, there was no significant difference among treated groups for red blood cells count. With respect to the changes in lymphoid organs weight, the present results showed that the relative bursa weight was significantly decreased in a group injected with egg yolk containing immunoglobulin against IBDV + NDV compared to control group. The groups that are injected with egg yolk containing Ig against IBDV or NDV had significantly higher relative thymus weight compared to other groups. There was no significant difference among the treated groups for antibody titer against both NDVand IBDV.
Key words: Broiler, NDV, IBDV, Immunoglobulin

Physiological studies on turkeys

Sherif Zayed, 2012


The responses of growing turkey to different dietary levels of betaine were investigated during the period from 12 to 20 weeks of age. Therefore, a basal diet was formulated to contain 21.37% CP and 3057 Kcal ME/kg. This diet was supplemented with betaine at levels of 0, 0.75, 1.5 and 2.25 g/kg diet. Thus, there were four treatment groups; each was fed to 50 birds (males and females) divided equally into two sub-groups of 25 males and 25 females in each.
Live body weight, body weight gain, feed intake and feed conversion ratio were recorded in each group. Also, mortality rate was recorded at 12, 14, 16, 18 and 20 wks of age. Keel length, shank length, tibia length, thigh length and breast width for all experimental birds were measured at 12, 14, 16, 18 and 20 wks of age.
Blood samples were collected at the end of the growing period for the determination of some blood parameters. Histological sections from breast and thigh muscles were examined. Also, liver histology was illustrated.
The obtained results could be summarized as the following:
1. Growth performance parameters:
1. Birds in T3 (1.5 g betaine/kg diet) showed the highest (P<0.05) final LBW and total weight gain (TWG) as compared to control birds or those in other treatment groups.
2. There was nearly similarity in total feed intake/bird among the
experimental groups, reflecting the best feed conversion ratio of birds in T3 (1.5g betaine) as compared to birds in other groups.
3.Males showed higher (P<0.05) final weight, feed intake and total gain,
and the better feed conversion ratio than females.
4.The interaction effect between betaine treatment and sex on all growth performance parameters was not significant.
2.Body measurements:
1.The superiority in final LBW of birds in T3 was associated with
improvement (P<0.05) in body measurements including breast width and length of keel, back, shank, tibia and thigh as compared to other groups.
2.Birds in other treatment groups (T2 and T4) did not differ significantly in growth performance parameters from that of the control birds.
3.Males showed higher (P<0.05) body measurements than females.
4.The interaction effect between betaine treatment x sex on all body measurements was not significant.
3.Blood parameters:
3.1.Protein metabolites:
1.Concentration of total proteins (TP) and albumin (AL) in blood plasma of turkey birds in T3 and T4 increased (P<0.05) as compared to the control ones. Globulin (GL) concentration increased (P<0.05) in T4. Concentration of creatinine and uric acid in blood plasma of birds was not affected by betaine treatment.
2.Males showed significantly (P<0.05) higher concentrations of total
protein and albumin, albumin: globulin ratio and creatinine than females.
Concentration of globulin and uric acid was not affected by sex of birds.
3. The interaction effect between treatment x sex on all protein metabolites was not significant.
3.2. Lipid metabolites:
1. Concentration of total lipids, triglycerides, LDL and HDL in blood plasma of birds was not affected significantly by feeding birds on diet
containing different levels of betaine as compared to the control diet. However, only concentration of total cholesterol in blood plasma of birds showed marked reduction by feeding betaine diets, but the differences were significant (P<0.05)with betaine supplementation at a level of 0.75 g/kg.
2. Females showed significantly (P<0.05) higher concentration of total
lipids, triglycerides and HDL than males. Concentration of total cholesterol and LDL was not affected by sex of birds.
3.The effect of interaction between betaine treatment and sex on concentration of lipid metabolites in this study was not significant.
3.3.Enzyme activity:
1.Feeding birds on diet containing 2.25 g/kg (T4) significantly (P<0.05) increased ALP activity as compared to the control, while did not differ significantly from birds in other betaine treatment groups. Activity of ALT, AST and ALT/AST ratio was not affected by betaine treatment, although activity of AST and ALT/AST ratio tended to increase and ALT activity tended to decrease in all betaine treatment groups as compared to the control group.
2.Males showed significantly (P<0.05) higher activity of AL T and lower ALP activity than females. Activity of AST and AST/ALT ratio was not affected by sex of birds.
3.The effect of interaction between treatment and sex on all enzymatic activity in this study was not significant.
4.Carcass quality:
1.Birds in T3 showed the highest (P<0.05) weights of carcass, giblets, gizzard, liver and heart as well as the highest percentage of giblets to preslaughter weight.
2.Birds in T2 showed the highest (P<0.05) weights of liver or heart relative to pre-slaughter weight. Weight of carcass and gizzard percentages as well as dressing percentage were not affected by dietary betaine treatment.
3.Birds fed diet contained 1.5 g betaine/kg (T3) showed significantly
(PSO.05) the longest major, heaviest and longest minor muscles as well as the longest thigh, while, feeding betaine at a level of 2.25 g/kg significantly (P<0.05) decreased thigh weight as compared to other treatments and controls. However, weight of major muscles and weight and percentage of breast meat were not affected significantly by betaine treatment.
4.Males showed higher (P<0.05) weights of carcass, giblets, gizzard, liver and heart. Females showed the higher (P<0.05) weights of giblets, gizzard and liver percentages.
5. Males showed significantly (P<0.05) higher weights and percentages of major, minor, thigh and breast than females.
6.The interaction effect between betaine treatment x sex on all carcass
traits was not significant.
5.Economic efficiency:
Viability rate was 100% in betaine treated groups and even in the control one. Although birds in T3 showed similar feed intake and higher feeding cost, they had the highest total gain and consequently the highest price of total gain. Therefore, from the economic point of view, birds in T3 showed the highest economic feed efficiency (EFE %) as compared to other treatment groups, reflecting the highest relative EFE to the control birds. Males showed higher EFE than females.
6. Histological study:
Histological examination of breast, thigh muscle and liver sections from different treatment groups showed that the intermediate level of betaine (1.5g/kg) was the best for enhancing muscles growth (breast and thigh muscles) and liver histogeneses in turkeys.
In conclusion, growth performance parameters, body measurements, carcass traits and economic efficiency of grower turkey were improved without adversely effects on protein metabolism, lipid metabolism, enzyme activity and the histological structure of the muscles and liver by supplementing diet with betaine at level of 1.5 g/kg as compared to lower (0.75 g/kg) or higher (2.25 g/kg) betaine levels.

Studies on improving quality of low fat Ras cheese

Zeinab Abd El-Salam, 2011


Low fat foods including milk and milk products have an important role for consumers having healthy problems or nutrition disorders; on the other hand removal or reducing fat levels adversely affect the flavor and texture of low fat dairy products. Ras cheese is the most famous and favorable hard cheese in Egypt, so this study was designed to improve the quality of low fat Ras cheese. The study included the effect of using partial homogenization, 0.3% emulsifiers and 0.1 % emulsifying salts on the chemical, microbiological properties and sensory attributes of low fat Ras cheese. In addition to the effect of using 1 % of probiotic bacteria (L. gasseri, L. johnsonii) with yoghurt culture either in a single or mixed culture in addition to the effect of using 0.5% of kefir or 1 % of aroma cultures on the quality of low fat Ras cheese. Results indicated that using partial homogenized milk, 1 % of probiotic bacteria with yoghurt culture or 0.5% of kefir culture improved flavor and texture (sensory attributes), and increased the contents of S.N. /T.N. and T.V.F.F.A. of low fat Ras cheese. Results also showed that cheese made from a combination of partial homogenization, probiotic bacteria or kefir culture gained higher scores of sensory evaluation and the counts of probiotic bacteria were in accordance with the recommended counts to get the healthy beneficial effect compared to control cheeses.
Key words: low fat Ras cheese, partial homogenization, probiotic bacteria, aroma starter culture.

Effect of growth prompting on productive and reproducdtive perfoemance of heifers

Mohamed El-Samahy, 2011


The objective of this experiment was to evaluate the effects of altered forage: concentrate ratio and DL-methionine analog supplementation on growth performance of growing heifers until confirmed pregnant. Twenty-four Holstein heifers with an average of age 5.6 ± 0.36 mo and weight 116 ± 6 kg, were fed restricted intakes formulated to allow for 800 g/d (NRC, 1989). Experimental diets were formulated to contain either 50: 50 (low forage) of 75: 25 (high forage) forage: concentrate ratio diets (DM basis). Forage comprised of com silage and constant amounts of berseem hay (1.5 and 2 kg/ h/ d for low and high forage, respectively). Treatments were fed with or without methionine hydroxy analog supplementation (MHA, 2.] g /day/ 100 kg BW). Live body weight was taken biweekly, while some body measurements and blood samples were taken monthly. Blood plasma was taken twice weekly after insemination to determine the plasma progesterone concentration. Digestibility trial was performed at 370 kg BW, during the digestibility trial heifers were fed individually in tie-stall. Actual intakes of nutrients were lower than expected intakes due to lower com silage DM ratio. DM, OM, CP, and NFE digestibility were significantly (P < 0.05) improved by reducing the forage portion of the diet, hoverer CF digestibility had a significant (P < 0.05) opposite direction. While, supplementation of MHA resulted in trends toward increased DM digestibility. Ruminal TVF A were significantly higher in low forage groups, however, ruminal PH was higher in low forage groups,while MHA trend to decreased TYF A only.lnsignificant differences were observed for plasma total protein triglyceride, creatinine, urea, in addition to negligible difference for albumin, globulin, and A/G ratio, while significant (P < 0.05) decreasing in plasma cholesterol was recorded for low forage without MHA treatment, also high forage without MHA group showed a trend to decreased plasma urea. Throughout the feeding period, ADG was not affected across all treatment rations (0.681 LF, 0.685HF, 0.695 LFM, and 0.663 HFM, SE± 0.033 kg/d). Gain of heifers body weight and measurements were not different among treatments. However, low forage groups had better feed¬ conversion for DM, ME and TDN, while CP and DCP conversion were better in high forage groups. Age at 330 kg BW was recorded an average of 15.98 mo (15.85 LF, 16.26 HF, 15.41 LFM, and 16.38 HFM, SE± 0.53 mo), as well as BW at age 14 mo and age and BW at AI, or conception not affected by treatments. Total and daily feed cost for high forage groups was significantly (P < 0.05) better than low forage groups, but total and gain feed cost from 150 to 330 kg BW did not affect by treatment may be due to the deep gap within treatments, especially in high forage groups. Thus, we can feed growing heifers in
this tested forage strategy under quality recommended for feedstuffs, and used satisfactory method for feeding. Notwithstanding, MHA addition did not has effect on growing heifers performance, nevertheless MHA addition may has influences on DM digest and blood metabolism, and may be the amount used under this experimental was not enough to improve growth performance.
Keywords: growing heifers, forage: concentrate ratio, DL¬methionine, forage strategy, nutrients digestibility, rumen parameters, blood plasma parameters, growth and reproductive performance, plasma progesterone.

Genetical and phenotypical variation of growth curve of Saidi and Farafra lambs

Sherif Aziz Melak, 2010


Determine the efficiency of five models [Linear with two parameters (Ll), Linear with three parameters (L2), second order polynomial (Quadratic), Brody and Richards models to the growth curves of Farafra and Saidi lambs by using monthly records of live weight from birth to 540 days of age were the first goal of this study.The second goal was studying the fixed effects affecting the studied parameters and finally estimates heritabilities for growth curve variables and genetic correlations between these variables.
Data used in the present study were collected from the experimental stations of the Animal Production Research Institute (APRI), Ministry of Agriculture and Land Reclamation, during the years from 1992 to 2005 on two different sheep breeds and locations, Farafra (F) lambs raised at Mallawi experimental station and Saidi (S) lambs raised at Seds experimental station. Farafra data started from year 1992 while Saidi data started from year 1994. A total number of 2559 Farafra and 1539 Saidi lamb records, progeny of 66 and 34 sires, 681 and 318 dams, respectively were available for this study. A Multiple Trait Derivative Free Restricted Maximum Likelihood program (MTDFREML; Boldman et al., 1993) was used to estimate the heritability and genetic correlation with Best Linear Unbiased Prediction (BLUP) methodology.
Least squares analysis of variance option, available in SAS software (SAS, 2004) was used to determine the effect of sex (male or female), type of birth (single, twin or triple), age of dam at lambing which classified into four classes 11 - 29, 30 -44, 45-64 and 65 - 150 month for Farafra breed and 14 - 29, 30 - 43, 44 - 60 and 61 - 124 month for Saidi breed (this classification according to the number ewes on each class, trying to make the number on each class very close to others), year of birth (every year including three successive lambing seasons) and season of birth (February, June or October) on the selected growth curve parameters.

The models were evaluated according to coefficient of determination (R2 values), Akaike's information criterion (AIC) and Bayesian-Schwarz information criterion (BIC). In both breeds, all models fitted the data, with high R2 ranged from 98.32 to 99.82 for over all mean, from 98.65 to 99.85 for males and from 98.79 to 2 99.72 for females. The Brody model gave the best R value of 99.85 in Saidi male, while the Quadratic model gave the lowest R value of 98.32 in Farafra over all mean The AIC and BIC values were lower in Quadratic and Richards models for Farafra and Saidi lambs, respectively than other models.
Absolute Growth Rate (AGR) obtained from L1, L2, Quadratic, Brody and Richards models for Farafra was 0.14, 0.13, 0.10, 0.13 and 0.13 respectively, while for Saidi was 0.13, 0.12, 0.10, 0.11 and 0.12 respectively, in the first month and decreased gradually until reach 0.03, 0.04, 0.04, 0.02 and 0.02 for Farafra and 0.03, 0.04, 0.03, 0.02 and 0.02 for Saidi at 540 days of age, respectively.
Maturing rate obtained from Brody and Richards models for Farafra was 0.0032 and 0.0036 respectively, while for Saidi was 0.0028 and 0.0036 respectively, in the first month and decreased gradually until reach 0.0005 and 0.0005 for Farafra and 0.0006 and 0.0005 for Saidi at 540 days of age, respectively.
Degree of maturing obtained from Brody and Richards models for Farafra was 8.06 and 7.95 respectively, while for Saidi was 6.28 and 6.74 respectively, in the first month and increased gradually until reach 85.96 and 84.63 for Farafra and 81.38 and 84.78 for Saidi at 540 days of age, respectively.
Sex showed significant influence (P<0.0l) on all growth curve parameters except on parameters A and K in Brody model for Farafra sheep that was not significant. Type of birth was significantly influenced (P<0.0l) all growth curve parameters except parameter K in Brody model for Farafra sheep that was not significant. Age of dam significantly influenced (P<0.0l) most growth curve parameters. Year of birth was the major source of variation (P<0.0l) where it significantly affected all growth curve parameters. Season of birth significantly influenced (P<0.0l) all growth curve parameters except parameter A in Brody model for Farafra and Saidi sheep and parameters A and M in Richards model for Farafra sheep that was not significant (P>0.05).
Parameters A, B, C (K) and M were moderately to highly heritable in Farafra lambs (h2=0.24 to 0.74). Genetic correlations between parameters were all positive and ranged from 0.35 to 1.00. In Saidi lambs, parameters had low to moderate heritabilites (0.01 to 0.60). Genetic correlations between parameters ranged from -0.87 to 1.00.
The results of this study suggest that Richards model [Yt = A (1 – Be-KT)m + et ] for growth monitoring can be useful in Farafra and Saidi breeds under both station conditions.
Keys words: growth models, heritability, genetic correlation, Farafra and Saidi lambs, fixed effects.

Effect of passive immunity on weight gain postpartum of Egyption buffalo

Nashwa Kamel, 2009


The present study was carried out at the Eastern farm, Faculty of Agriculture, Cairo University, Giza, Egypt. Twenty late pregnant Holstein Friesian cows and Egyptian buffaloes were used (10 each). The animals were divided randomly into 4 symmetric groups, 5 cows and 5 buffaloes as control were injected with 4ml 0.9% Na CI at -30 and -15 days prepartum and another 5 cows and 5 buffaloes as vaccinated group were injected with 4ml Scour Guard 3@ (K) following the same regieme.
The data showed that Suckling colostrum from immunized dams using Scour Guard 3@ K in -30 and -15 days prepartum improved (P<0.05) offspring body weight by 6.5 %. The results are showed that using Scour Guard 3@ (K) had a significant effect on dam serum IgG which increased in the vaccinated group compared to the control group by 74.4%, being higher in buffaloes than cows by 44.23% (39383 vs. 27306). Serum total protein (TP), albumin (A), and globulin (G) were the highest (p<0.05) in the vaccinated groups.
Concerning the offspring serum, suckling from their dams treated with Scour Guard 3@ (K) caused an increase (P<0.05) in their serum total IgG 105.9% but being higher in buffalo's than cow's offspring by 9.42% (33633 vs. 30738). Vaccination of heir dams with Scour Guard 3@ (K) increased (P<0.05) serum total protein and globulin in the. offspring serum but this increase was higher in buffalo than cows by 15.61%(5.2210 vs. 3.9406) . No significant effects were recorded for (alb) concentration and (A/G) ratio among the vaccinated and control groups.
Using Scour Guard 3@. (K) resulted in a significant increase in serum antimicrobial potency of the vaccinated group comparing to the control group. But, the antimicrobial potency was significantly (p<0.05) higher in buffaloes than cows by 57.8%. Also, the antimicrobial potency increased significantly (p<0.05) in offspring serum in both breeds. Antimicrobial potency of dam's milk, significantly (p<0.05) increased due to the vaccination, buffaloes responded better than cows in their milk antimicrobial potency.
In conclusion, treatment with Scour Guard 3@ (K) at -30 and -15 days prepartum ,successfully increased serum IgG levels in dams and the suckling young. The antimicrobial potency of dam's milk and offspring serum significantly increased using ~his vaccination. Also the daily weight gain was increased. Buffaloes responded better than cows to the vaccination of Scour Guard 3@ (K).
Key words: Immune colostrum, IgG, Scour Guard 3@ (K), Antimicrobial potency and daily weight gain.

Effect of adding transglutaminase on the properties of fermented milk

Amina Abd El-Hady Hassan El-Shreef, 2009


Rheological, chemical and organoleptic properties of yoghurt made from (buffaloes', cows' and goats' milk) were studied by adding Microbial Transglutaminase (MTGase) at different ratios and the results showed that:
1. Adding MTGase at different concentrations decrease the development of acidity, syneresis and acetaldehyde. Also, increased the values of firmness, apparent viscosity and organoleptic properties.
2. Buffaloes' milk yoghurt showed the highest firmness, apparent viscosity and organoleptic properties. Meanwhile it had the lowest syneresis and acidity development.
3. Cows' milk yoghurt showed intermediate values between (buffaloes' and goats' milk yoghurt) for rheological, chemical and organoleptic analysis. On the other hand, it had the lowest value of acetaldehyde (aroma compound).
4. Goats' milk yoghurt showed the highest acetaldehyde, syneresis and development of acidity but it had the lowest firmness and apparent viscosity.

Using some salts to alleviate heat stress and improve physiological responses in sheep under hot conditions in Egypt

Ayman Khalil, 2008


This study was carried out in Minia Governorate, Mallawi Experimental Station, Animal Production Research Institute (APRI), Agriculture Research Center (ARC), Ministry of Agriculture in cooperation with Animal Production Department, Faculty of Agriculture, Minia University during the period from June to August 2006.
This study was carried out by using 90 animals (75 Farafra mature ewes aged 2.5 to 4 years old, averaged 39.69 kg of body weight and 15 Farafra mature rams aged 2 to 3.5 years old, averaged 59.27 kg of body weight). The aim of this study was to investigate the effect of using some salts to alleviate heat stress and improve physiological responses in sheep under hot environmental conditions in Egypt.
The experimental animals (rams and ewes) were equally divided randomly to five treatment groups according to their age and initial body weight as follow: control, 1 % Sodium bicarbonate (G,), 1 % Potassium carbonate (G2), 0.5% Sodium bicarbonate + 0.5% Potassium carbonate (G3) and 1 % Sodium bicarbonate + 1% Potassium carbonate (G4). These diet. contains varying levels of DCAD (Na + K - Cl) mEq/kg of DM (115, 246, 276, 257 and 407 for control, G1, G2, G3 and G4, respectively). All animals were subjected to the routine vaccination programs for infectious diseases (foot and mouth disease, rift valley fever, etc.). There are five concentrate mixtures with salts used in this experiment .The concentrate mixtures contained 14% crude protein and 50% starch value. At 8.00 am animals were fed wheat straw in addition to a concentrate mixture.
Climatic conditions:
Ambient temperature (AT) and relative humidity (RH) were recorded simultaneously during the experimental period at morning (6-8 a.m) and afternoon (12-2) p.m.
Physiological parameters:
1. Blood hematocrit and hemoglobin concentration.
Blood samples (10 ml) were collected every 10 days from each animal via Jugular vein using glass tubes. Each blood sample was divided into two parts (heparinized and non - heparinized). Hemoglobin concentration (Hb, g/l) was measured by colorimetric methods. Hematocrit value (Ht) was measured in hematocrit capillary tubes using a hematocrit centrifuge.
2. Serum analysis.
Unheparinized blood samples were centrifuged at 3000 r.p.m for 15 minutes. Serum total protein (TP), urea and glucose concentrations were determined by an enzymatic calorimetric method.
Serum Na and K concentrations were determined using enzymatic measuring. Chloride was determined using Thiocyanate method. Direct radioimmunoassay (RIA) technique was performed for determination of serum hormones . triiodothyronine, thyroxine and testosterone.
3. Thermal responses.
Rectal temperature (RT, °C) was measured using a clinical thermometer. Skin temperature CST, °C) and ear temperature (ET, °C) were measured using infrared thermometer (Radioshack).
4. Respiratory activities and gas exchange.
Respiration rate (RR) was measured by. counting the flank movements in one minute. Respiratory minute volume of exhaled air/minute was measured by Dry Gas Meters (liters) and gas volume was corrected to Standard Dry Temperature and Pressure (STPD). Volume of oxygen consumption (Vo2), carbon dioxide production (VCo2) and respiratory quotient (RQ%) were measured with the open-circuit technique.
5- Reproductive performance :
5.1 Rams.
Semen physical characteristics of rams were evaluated, Ram were examined and trained for semen collection two months before the experiment. Semen samples were collected using artificial vagina once each 10 days. Immediately after, ejaculation, semen samples were placed in water bath at 37°C. Semen was evaluated in term of (pH, volume, motility, sperm concentration, live, dead sperm and abnormal spermatozoa counts).
5.2 Ewes.
Conception rate and embryonic mortality during the mating season were determined by using sonar. Two examinations were taken. The first was after 40 days post mating and the second was after 85 days post mating.
The results can be summarized as follows:
1. Dietary electrolytes increased insignificantly blood Hb and significantly decreased (P<0.05) blood Ht in both rams and ewes.
2. The values of glucose, total protein, Na and K tended to significantly increase (P<0.05), DEB values were significantly increased (P<0.0l), serum urea values were increased insignificantly and serum CI tended to significantly decrease (P<0.05) in both rams and ewes by dietary salts.
3. Dietary salts insignificantly increased serum triiodothironine and thyroxine of rams and ewes and significantly increased (P<0.05) serum testosterone of rams.
4. Dietary electrolytes significantly increased (P<0.05) semen pH, ejaculate volume, sperm motility, live sperm percentage, sperm concentration per ml, while significantly increased (p<0.01) sperm concentration per ejaculate and significantly decreased (P<0.01) abnormal sperm percentage.

5. Sonar results indicated that dietary salts had a beneficial effect on conception rate and decreasing embryo mortality specially, in the third treatment group (G 3).
6. Treated rams and ewes had a significant (P < 0.01) decrease in the value of rectal temperature, skin temperature at morning (6-8 a.m) and afternoon (12-2p.m) and significant (p<0.01) decrease in respiration rate.
7. Dietary salts insignificantly decreased ear temperature of ewes at morning. While, significantly decreased (p< 0.05) ear temperature in rams. And at afternoon ear temperature significantly decreased (p<0.05) of both rams and ewes.
8. Gas volume and tidal volume significantly increased (p<0.05) by dietary salts in both rams and ewes.
9. Dietary salts significantly increased (p<0.05) VO2 of rams and ewes. While, at the same time insignificantly decreased VCO2 in both rams and ewes. Also, dietary salts decreased significantly (p<0.01) RQ.