Pharmacokinetics and pharmacodynamics of chlorpyrifos in male and female cattle after topical administration

The aim of this work was to study the pharmacokinetic behaviour and the inhibitory effect on acetylcholinesterase and butyrylcholinesterase activities of chlorpyrifos in male and female cattle after pour-on administration. Determination of cholinesterase activity in plasma and erythrocyte was carried out according to Ellman kinetic method. The mean baseline activities were 9338.39 ± 1331.61 and 13220.69 ± 2274.18 to acetylcholinesterase and 624.65 ± 39.32 and 641.68 ± 88.08 IU/L to butyrylcholinesterase in females and males, respectively. Acetylcholinesterase was the predominant form of cholinesterase analyzed, with low levels of butyrylcholinesterase. The basal acetylcholinesterase activities of the bulls were significantly greater than those of cows. The inhibitory effect of topical chlorpyrifos administration was lower on butyrylcholinesterase than on acetylcholinesterase. Chlorpyrifos peak plasma concentration (male:10.920 ± 4.18; female:12.12 ± 3.88 μg/L) were reached at 11.92 ± 9.19 and 8.17 ± 7.67 h in male and female, respectively. The values of area under curve were 185.96 ± 168.45 and 278.89 ± 270.00 μg·h/L and mean residence time were 13.95 ± 8.10 and 14.90 ± 9.80 h in male and female, respectively.     

Relationship of age to body weight,scrotal circumference,testicular ultrasonograms,and semen quality in Sahiwal bulls

The objective of the present study was to determine the relationship of age to body weight (BW), scrotal circumference (SC), number of pixels of testicular ultrasonograms (NP), and semen quality in Sahiwal bulls. The study was based on 128 Sahiwal bulls of different age groups (from 0 to >100 months of age). Bulls were evaluated for SC, BW, and NP. Semen was evaluated once a week for five consecutive weeks from regularly collected donor bulls (n = 86) ranging in age from 25–30 to >100 months. Ejaculate volume, sperm motility, sperm concentration, sperm morphology, percent live sperms, sperm plasma membrane integrity, and normal acrosome were compared among different age groups. Mean SC and BW increased (P < 0.05) in a curvilinear manner from birth to >100 months of age. Mean NP of testicular ultrasonograms increased (P < 0.05) from 0 to 24 months and then plateaued until >100 months of age. Body weight, SC, and NP were positively correlated with age from birth until >100 months (r = 0.91, 0.87, and 0.40, respectively). Ejaculate volume (5.7 ± 0.2 vs. 4.6 ± 0.09 ml) and sperm concentration (1,281.6 ± 17.7 vs. 1,115.8 ± 55.9 × 10⁶/ml) increased (P < 0.05) in mature bulls compared to younger ones. However, motility (68.6 ± 0.3%), plasma membrane integrity (50.8 ± 1.0%), and normal acrosome (74.8 ± 0.5%) remained insignificant due to age. In six of eight age groups studied, morphological abnormalities were well within the range (18.1 ± 0.3%). In conclusion, the BW, SC, and NP of testicular ultrasonograms, ejaculate volume, and concentration increased with age. Moreover, semen quality is fairly independent of age except volume and concentration in Sahiwal bulls.     

Circadian rhythm of metabolic changes associated with summer heat stress in high-producing dairy cattle

The current study aimed to investigate the circadian rhythm of blood metabolic parameters associated with summer heat stress (HS) in dairy cows. Ten healthy lactating Holstein Friesian cows were followed during HS for three successive days at six different time points. Blood was sampled from each cow starting from 07:00 am; at 4-h intervals. Ambient air temperature and relative humidity were recorded, and temperature-humidity index (THI) was calculated as well. Respiration rate (RR) and rectal temperature (RT) were recorded for each cow at the time of blood sampling. Concentrations of glucose, non-esterified fatty acids (NEFA), total cholesterol (TC) and urea were measured in each blood sample. The THI values were >68 at all times of the day, and the highest values were recorded at 11:00 am, 03:00 pm and 07:00 pm (80.9, 83.7, and 80.8, respectively). All the cows showed a significantly higher RR and RT coinciding with higher THI values (93 ± 4 and 39.6 ± 0.1; 90.2 ± 3.4, and 40.1 ± 0.1; 87.6 ± 4.1, and 39.8 ± 0.1, respectively, P < 0.05). The concentrations of glucose were the lowest at 11:00 am and 03:00 pm (3.75 ± 0.1 and 3.44 ± 0.1 mmol/L, respectively, P < 0.05). Decreased glucose concentrations coincided with increased NEFA concentrations, (0.43 ± 0.01 and 0.56 ± 0.02 mmol/L, respectively, P < 0.05), and were highly negatively correlated (r = −0.50, P < 0.001). The highest urea and TC concentrations were registered at 11:00 am (6.11 ± 0.15 mmol/L and 109.9 ± 2.2 mg/dl, respectively) whereas the lowest urea and TC values were recorded at 03:00 am (4.97 ± 0.18 mmol/L and 99.5 ± 1.7 mg/dl, respectively, P < 0.05). The results of the present study indicate that there was a circadian variation in glucose, NEFA, urea, and TC resulting in the most unfavorable metabolic condition during the hottest moment of the day in dairy cattle. Earlier work revealed that HS-metabolic changes are reflected in the follicular fluid. The circadian changes observed in the present study associated with HS may imply that also the microenvironment of the oocyte is affected.     

Effect of age and season on semen quality parameters in Sahiwal bulls

The objective of the study was to determine the effect of season, period, age, bull, and ejaculate on semen quality in Sahiwal bulls. Semen production records from 1996 to 2006 of 5,483 ejaculates from 46 Sahiwal bulls maintained at Artificial Breeding Complex, NDRI, Karnal, India were analyzed using least square analysis of variance by LSML software package. The overall least squares means of ejaculate volume (VOL), total volume per day (VOLD), mass activity (MA), initial motility (IM), sperm concentration per ml (SPC), and sperm concentration per ejaculate (SPCE) were 3.79 ± 0.02 ml, 5.81 ± 0.06 ml, 2.32 ± 0.01, 55.47 ± 0.001%, 766.69 ± 5.50 × 10⁶/ml and 3023.25 ± 30.15 × 10⁶, respectively. All semen traits (VOL, VOLD, MA, IM and SPCE) were significantly (P < 0.01) affected by age groups, season and period, whereas season had significant effect on VOL at 5% level. During hot-humid season, highest value of VOL, VOLD, MA, IM, SPC, and SPCE were observed followed by summer and cold season. Highest value of VOL, VOLD, IM, and SPCE were observed during period-3 (2004–2006), whereas highest value of MA and SPC were observed during period-1 (1996–1999). However, lowest magnitude of MA, IM, SPC, and SPCE during period-2 (2000–2003) was observed. Ejaculate characteristics like VOL, VOLD, and SPCE increased with the increasing age of bull up to 5 years and then decreased. Significant (P < 0.01) bull to bull variation was found in VOL, VOLD, MA, IM, SPC, and SPCE traits. First ejaculate had significantly (P < 0.01) higher MA, IM, SPC, and SPCE. Hence, it could be concluded that during rainy season and period-1 and period-3 the quality of semen is quantitatively and qualitatively good. Better quality semen was obtained up to 5 years of age in Sahiwal bulls.     

Effect of FMD vaccination on semen quality parameters in Karan Fries and Murrah buffalo bulls

Effect of Foot and Mouth disease (FMD) vaccination was studied on semen quality parameters of 19 Karan Fries (KF) and eight Murrah (MU) breeding bulls during the period 2002 to 2004 at Artificial Breeding Complex, NDRI, Karnal. A total of non-vaccinated 155 KF and 72 MU bulls' ejaculates were taken as control, while 169 KF and 51 MU bulls' ejaculates, collected after vaccination, were used to study the effect of vaccination stress. The results showed that FMD vaccination had no significant (P > 0.05) effect on ejaculate volume and total volume per day of semen in both KF and MU bulls. Volume of semen increased slightly during post-vaccination period in both the breeds. After FMD vaccination, there was significant (P < 0.01) decrease in mass activity (2.27 ± 0.06 vs. 1.67 ± 0.07 and 2.49 ± 0.09. vs. 1.75 ± 0.10, for KF and MU, respectively), initial motility (56.89 ± 0.03% vs. 44.62 ± 0.02% and 62.26 ± 0.04% vs. 47.08 ± 0.05%, for KF and MU, respectively), sperm concentration (754.19 ± 23.96 vs. 554.14 ± 22.95 × 10⁶/ml and 848.61 ± 33.65 vs. 571.57 ± 39.99 × 10⁶/ml, for KF and MU, respectively), and total sperm output per ejaculate (3,685.94 ± 158.40 vs. 2,781.54 ± 151.70 × 10⁶ and 2,218.75 ± 133.14 vs. 1,582.84 ± 158.20 × 10⁶, for KF and MU, respectively). Application of FMD vaccine had significantly (P < 0.05) adverse effect on most of the seminal attributes during post-vaccination in KF and MU buffalo bulls. So, the spermiograms affected following vaccination suggest that in bovines, the semen collection and preservation should be suspended till normal fertility of sperm is restored to avoid the failure of conception from artificial insemination using such semen.     

Comparison of three commercially available prescription diet regimens on short-term post-prandial serum glucose and insulin concentrations in healthy cats

Dietary therapy is an important treatment component for diabetes mellitus (DM). In this study, the impact of three different commercially available diet regiments (1 general use and 2 aimed for treating obesity and DM) on short-term post-prandial serum glucose and insulin concentrations of five healthy cats to better understand what impact each of these diets may have for diabetic cats. The diet regiments used in this study were as follows: C/D dry (General Use- Low protein, High fat, High carbohydrate, and Low fiber), M/D dry (DM- High protein, High fat, Low carbohydrate, and High Fiber), and W/D dry (DM- Low Protein, Low Fat, High Carbohydrate, and High Fiber). No significant difference in post-prandial serum glucose levels were observed with the C/D (84.6 ± 1.5 mg/dl) and W/D (83.8 ± 1.4 mg/dl) dry diets when compared to pre-prandial fasting levels (83.9 ± 1.4 mg/dl). However, a significant reduction was observed with the M/D diet (78.9 ± 0.8 mg/dl) which had 50-60% less carbohydrates than either C/D or W/D diet. Unlike what was observed with post-prandial glucose levels, an interesting pattern emerged with post-prandial insulin levels, which were increasing with W/D, C/D, and M/D diets in that order (1.1 ± 0.2, 1.7 ± 0.2, and 2.3 ± 0.2 ng/ml respectively). Most surprising, though, was the fact that the W/D diet did not seem to stimulate insulin secretion as compared to pre-prandial levels (1.1 ± 0.1 ng/ml) in healthy cats. Interestingly, the W/D diet had high levels of carbohydrate and low levels of protein. Coincidentally, the only diet (M/D) which had a significant reduction in post-prandial glucose also showed the highest increase in post-prandial insulin in healthy cats. Therefore, dietary amounts of carbohydrate, fat, protein and fiber can all have an individual impact on post-prandial glycemia and subsequent insulin requirement levels. Just as concepts regarding dietary management of people with DM are evolving, investigators are reassessing what constitutes the ideal diet for the diabetic feline. As such, having a better understanding for each dietary component, may lead us to better understand how we can synergize certain dietary components to aid in DM management.     

Effect of pre-weaning selection on estimates of genetic parameters and breeding values for post-weaning growth rate of beef bulls on test

Data on South African Angus cattle consisting of 45 259 records on weaning weight (WWT), 4 360 records on average daily gain from on-farm test (ADG-D) and 1 118 from centralized test (ADG-C) were analyzed to evaluate the effect of pre-weaning selection on estimates of genetic parameters and subsequent estimated breeding values (EBV) for post-weaning average daily gain. (Co)variance components and genetic parameters for weaning weight (WWT), ADG-C and ADG-D were estimated by REML procedures fitting three different animal models. Model 1 was a univariate model of WWT, ADG-C or ADG-D and did not account for the effect of pre-weaning selection on post-weaning ADG. Model 2 was a two-trait model of WWT and either ADG-C or ADG-D. Model 3 was a multi-trait animal model including WWT, ADG-C and ADG-D. Estimates of heritability for ADG-C were 0.39 ± 0.080, 0.42 ± 0.060 and 0.44 ± 0.010 from Model 1, 2 and 3 respectively. Corresponding estimates for ADG-D were 0.18 ± 0.020, 0.19 ± 0.020 and 0.21 ± 0.020 respectively. Rank correlations based on EBVs for ADG-C for all bulls were 0.92, 0.83 and 0.94 for Model 1 vs. Model 2, Model 1 vs. Model 3, and Model 2 vs. Model 3, respectively and they indicated a possible re-ranking of bulls when including or excluding a correlated pre-weaning trait. Rank correlations for ADG-D also followed a similar trend. Inclusion of pre-weaning information in genetic analysis for post-weaning average daily gain is necessary to account for selection at weaning.     

Investigation of serum concentrations and immunohistochemical localization of α1-acid glycoprotein in tumor dogs

The purpose of this study was to measure the dynamics of serum α1-acid glycoprotein (AGP) concentration in dogs with various tumors, and to investigate the localization of AGP in some tissues using immunohistochemical staining. Sera were obtained from 171 dogs bearing tumors of various types. Serum AGP concentration was measured by single radial immunodiffusion. Tumors occurring in the liver and spleen were also investigated immunohistochemically using anti-canine AGP antibody. Mean serum AGP levels were 749 ± 602 mg/L in dogs with carcinoma (n = 39), 1,014 ± 971 mg/L with sarcoma (n = 18), and 887 ± 935 mg/L with round cell tumors (n = 46), all significantly higher than serum AGP level in healthy dogs (n = 137, 364 ± 106 mg/L). Mean serum AGP levels were significantly higher than in healthy dogs in complex mammary gland carcinoma (n = 5, 876 ± 721 mg/L), malignant melanoma (n = 7, 1,010 ± 821 mg/L), and hepatocellular carcinoma (n = 5, 936 ± 741 mg/L) among carcinomas, hemangiosarcoma (n = 5, 1,740 ± 1,323 mg/L) among sarcomas, and lymphoma (n = 19, 1,072 ± 965 mg/L) and histiocytic tumor (n = 6, 1,800 ± 1,387 mg/L) among round cell tumors. In an immunohistochemical investigation of AGP localization, both weak and strong staining for anti-AGP antibody were seen in hepatic tissue in dogs with primary non-tumorous lesions originating in the spleen (hematoma) and elevated serum AGP, but all tumor tissue in the spleen was negative. Among dogs with primary tumor lesions of the spleen (hemangiosarcoma) and elevated serum AGP levels, both weak, moderate and strong staining for anti-AGP antibody were seen in hepatic tissue, while strong positive staining was apparent in all tumorous tissue from the spleen. In primary tumor lesions in the liver (hepatocellular carcinoma), both moderate and strong staining for anti-AGP antibody were seen in normal hepatic tissue, and both weak, moderate and strong staining were seen in tumor tissues of the liver. AGP levels thus appear to be elevated in dogs with carcinomas, sarcomas, and round cell tumors. With some of these malignant tumors, localization of AGP in tumor tissue was seen.     

Investigation of selected biochemical indicators of Equine Rhabdomyolysis in Arabian horses: pro-inflammatory cytokines and oxidative stress markers

A total of 30 horses were divided into two groups, one served as a control whereas other was rhabdomyolysis diseased horses. After blood collection, the resulted sera were used for estimation of the activities of creatin kinase (CK), aspartate transaminase (AST), lactate dehydrogenase (LDH), lactic acid, triacylglycerol (TAG), glucose, total protein, albumin, globulin, urea, creatinine, Triiodothyronine (T₃), calcium, sodium, potassium, phosphorus, chloride, vitamin E, interleukin-6 (IL-6) and tumor necrosis-α (TNF-α). In addition, whole blood was used for determination of selenium, reduced glutathione (G-SH) and prostaglandin F2-α (PGF2α). The erythrocyte hemolysates were used for the determination of the activities of super oxide dismutase (SOD), catalase (CAT), total antioxidant capacity (TAC), nitric oxide (NO) and malondialdehyde (MDA). The present findings revealed a significant (p ≤ 0.05) increase in the values of CK, AST, LDH, glucose, lactate, TAG, urea, creatinine, phosphorus, MDA, TNF- α, IL6 and PGF2- α in diseased horses when compared with the control. Furthermore, the values of calcium, SOD, CAT, TAC, NO and GSH in diseased horses were significantly (p ≤ 0.05) lower than the control. The other examined parameters were not statistically significant. In conclusion, the examined pro-inflammatory cytokines were useful biomarkers for the diagnosis of Equine rhabdomyolysis (ER) in Arabian horses beside the old examined biomarkers. In the future, efforts should be made to confirm this in other breed. If this could be achieved, it would open up new perspectives in research fields dealing with ER.     

Bacteria flora and heavy metals in cultivated oysters <Emphasis Type="Italic">Crassostrea iredalei</Emphasis> of Setiu Wetland,East Coast Peninsular Malaysia

Slipper oyster Crassostrea iredalei is a species of good demand for its sweet flavor and white coloured flesh. The filter feeding nature predisposes oysters to accumulation of pathogenic and heavy metals in waters impacted by sewage pollutions and may thus render the oysters unfit for human consumption. A study was undertaken to investigate the presence of bacteria flora and heavy metal concentrations in cultivated oysters Crassostrea iredalei at Setiu Wetland, Terengganu, the only source of cultivated oysters in East Coast of Malaysia. A total of 200 slipper oyster samples were analyzed. The bacteria were isolated using non selective agar such as TSA agar and selective agars before they were then identified using conventional methods in combination with BBL Crystal identification kit. Heavy metals such as zinc (Zn), copper (Cu), cadmium (Cd), and lead (Pb) concentrations were determined using atomic absorption spectrophotometry. Results showed that the oysters harbor predominantly Shewanella putrifaciens followed by Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio cholerae, Enterobacter cloacae, Escherichia coli and Chromobacterium violaceum. They also contain high concentration of Zn (785.68 ± 285.88 μg/g) with the lowest heavy metal was Pb (0.17 ± 0.15 μg/g), whilst the concentrations of other heavy metals were Cu (38.9 ± 13.2 μg/g) and Cd (1.60 ± 0.28 μg/g). The study is very useful to evaluate the type of bacteria and heavy metal present in oyster meat for human consumption.     

A microbiological and serological study of leptospirosis among pigs in the Morogoro municipality,Tanzania

Serological and microbiological studies on leptospirosis in pigs from Morogoro municipality, Tanzania were carried out between October 2007 and May 2008. Serum samples (n = 385) from apparently healthy pigs were tested by microscopic agglutination test for antibodies against live cultures of six known Leptospira interrogans serovars: Pomona, Icterohaemorrhagiae, Ballum, Tarassovi, Grippotyphosa and Hardjo. Significant positive titres were detected in 4.42% (17/385) of all the tested serum samples. Asceptically collected samples, urine (n = 236) and kidney tissues (n = 214), were cultured in enriched Fletcher’s and Ellinghausen McCullough–Johnson and Harris media and assessed, at weekly intervals for 24 weeks, for growth by dark-field microscopy. Two leptospiral organisms were isolated from the urine samples. There was a statistical association between seroposivity and location that the subjects reside in (P < 0.05), whereas it was not significantly associated with sex nor age (P > 0.05). The evidence of pig exposure to different serovars and the isolation of the leptospiral organisms confirm that the infection is present in pigs although with an overall low prevalence. Apart from its economic importance on to the pig industry, this disease is a potential zoonotic public health risk in Tanzania, especially because of the lack of studies on leptospirosis among persons who handle pigs and pork products.     

Influence of <Emphasis Type="Italic">E. coli</Emphasis> lipopolysaccharide induced fever on the plasma kinetics of cefepime in cross-bred calves

The pharmacokinetic behavior of cefepime was studied in healthy and febrile cross-bred calves after single intravenous administration (10 mg/kg). The fever was induced with E. coli lipopolysaccharide (1 μg/kg, IV). The drug concentration in plasma was detected by microbiological assay method using E. coli (MTCC 739) test organism. Pharmacokinetic analysis of disposition data indicated that intravenous administration data were best described by 2 compartment open model. At 1 min the concentration of cefepime in healthy and febrile animals were 55.3 ± 0.54 μg/ml and 50.0 ± 0.48 μg/ml, respectively and drug was detected up to 12 h. The elimination half-life of cefepime was increased from 1.26 ± 0.01 h in healthy animals to 1.62 ± 0.09 h in febrile animals. Drug distribution was altered by fever as febrile animals showed volume of distribution (0.27 ± 0.02 L/kg) higher than normal animal (0.19 ± 0.01 L/kg). Total body clearances in healthy and febrile animals were 104.4 ± 2.70 and 114.2 ± 1.20 ml/kg/h, respectively. To maintain minimum therapeutic concentration of 1 μg/ml, a satisfactory dosage regimen of cefepime in healthy and febrile cross-bred calves would be 15.5 mg/kg and 8.2 mg/kg body weight, respectively, to be repeated at 8 h intervals. The T>MIC values (8 h) of cefepime suggested that this agent is clinically effective in the treatment of various infections.     

Circulating oxidative stress status in dromedary camels infested with sarcoptic mange

Oxidative stress is an imbalance between radical-generating and radical-scavenging activity, resulting in oxidation products and tissue damage. This study was aimed to evaluate the status of oxidative stress indices in blood of camels naturally infested with S. scabiei. Forty-seven male camels (Camelus dromedaries) were divided according to the extent of the infested area with Sarcoptes scabiei into four groups, mild (MID, n = 12), moderate (MOD, n = 10), severely infested (SEV, n = 10) and healthy control group (n = 15). Blood was used for determination of red cell count (RBC), hemoglobin (Hb), packed cell volume (PCV), serum nitric oxide (NO^•, a free radical), ascorbate and albumin concentrations, and erythrocytic values of malondialdehyde (MDA, a marker of lipid peroxidation), protein carbonyls (PC, an indicator of protein oxidation), glutathione (GSH) superoxide dismutase (SOD) and catalase (CAT). Decreased levels (P < 0.05) of RBC, Hb, PCV, albumin and ascorbate were noticed in MOD and SEV compared to controls with the lowest values (P < 0.05) in SEV except for ascorbate, where MOD did not differ from SEV. Compared to controls, NO^• gradually increased (P < 0.05) in MID followed by MOD and SEV, whereas MDA and PC were higher (P < 0.05) in MOD and SEV. PC was higher (P < 0.05) in MOD than SEV. In addition, the antioxidants GSH, SOD and CAT were higher (P < 0.05) in MID and lower (P < 0.05) in MOD and SEV compared to controls. GSH was lower (P < 0.05) in SEV compared to MOD. Besides, Hb was negatively correlated with NO^• (r = −0.68, P < 0.001), MDA (r = −0.53, P < 0.001) and PC (r = −0.73, P < 0.001). In conclusion, dromedary sarcoptosis is accompanied by a state of oxidative stress process, which increased by increasing the area of infestation, and may contribute to the pathogenesis of the disease.     

Equine placenta expresses glutamine synthetase

In most mammalian species the developing fetus utilizes large amounts of glutamine derived both from the maternal circulation and synthesized de novo in the placenta. The present study was designed to determine the role of the placenta in glutamine synthesis in the horse. The placentae from eight Standardbred mares were sampled immediately after parturition together with additional tissues obtained at necropsy from three Standbred mares during diestrous. Glutamine synthetase protein was detectable in the non-pregnant horn of the placenta in amounts similar to those seen in gluteus muscle, but the amount in the pregnant horn was two times greater than in the non-pregnant horn. Glutamine was the second most abundant amino acid in amniotic fluid at a concentration of 310 ± 26 μmole/L with that of glycine being 535 ± 48 μmole/L. The most abundant amino acids in placental tissue were glycine (3,732 ± 194 μmole/Kg), glutamate (3,500 ± 343 μmole/Kg) and glutamine (2,836 ± 208 μmole/Kg). The results illustrate the importance of glutamine to the equine fetus and establish that the placenta, particularly the pregnant horn, has considerable capacity for glutamine synthesis.     

Variability of hair coat and skin traits as related to adaptation in Criollo Limonero cattle

The variation in hair coat and skin histology traits of Criollo Limonero cattle was analyzed using 213 Criollo Limonero females. Skin biopsies were obtained from slick-haired (N = 16) and normal-haired (N = 14) animals. Measured traits included hair length (HL), color coat (CC), number of hair follicles per square centimeter (NHF), sweat glands per square centimeter (NSG), sweat glands size (SGS), sebaceous glands per square centimeter (NSBG), blood vessels per square centimeter (NBV), and thickness of epidermis (TE). Hair length differed (P < 0.001) between slick- and normal-haired animals (4.9 ± 0.12 vs 10.9 ± 0.20, respectively). Differences (P < 0.01) in CC (Bayo = 144/67.6% vs Red = 69/32.4%) and HL (slick-haired = 199/93.4% vs normal-haired = 14/6.5%) were found. Distribution of slick- and normal-haired animals differed (P < 0.01) between bayo-coated and red-coated (139/62.2% vs 9/4.2%; respectively). Most (P < 0.05) red-coated animals belonged to a single family. No differences (P > 0.05) were found between slick-haired and normal-haired animals in NHF (637 ± 164 vs 587 ± 144, respectively), NSG (556 ± 134 vs 481 ± 118, respectively), NSBG (408 ± 87 vs 366 ± 77, respectively), NBV (1628 ± 393 vs 1541 ± 346, respectively), and TE (1.24 ± 0.14 vs 1.32 ± 0.12, respectively). However, SGS was greater (P < 0.01) in slick-haired than normal-haired animals. In conclusion, Criollo Limonero cattle are predominantly bayo-coated, slick-haired, with a reduced number of hair follicles relative to Zebu cattle, sweat and sebaceous glands in proportion to hair follicle numbers, and with a high blood flow irrigating the skin. There is a sub-group of red-coated animals with yellow or cream skin, thicker epidermis, and with a higher frequency of normal-haired animals. It appears that the slick hair gene has been favored by natural selection in this breed.     

Effect of induced pyrexia on the disposition kinetics of ciprofloxacin in dogs

Ciprofloxacin was administered intravenously @ 5 mg/kg body weight to six healthy dogs. After a washout period of two weeks, fever was induced by injecting Escherichia (E) coli endotoxin. Ciprofloxacin was administered again. Blood samples were collected at various time intervals and analyzed for ciprofloxacin with HPLC. The kinetic analysis revealed the volume of distribution in healthy vs. febrile dogs as 2.12 ± 0.32 vs. 1.79 ± 0.43 L/Kg, respectively. The elimination half life was 2.23 ± 0.78 and 2.07 ± 0.74 hours in healthy and febrile dogs, respectively. Similarly, dogs under healthy and febrile conditions showed comparable total plasma clearance of 0.66 ± 0.06 and 0.60 ± 0.07 L/Kg/h, respectively. All these and other investigated kinetic parameters were statistically non significant. This study concludes that the pharmacokinetic behavior of ciprofloxacin is similar under healthy and febrile conditions. Thus, the kinetic studies of fluoroquinolones conducted in normal/healthy animals may be used to depict the pharmacokinetic parameters in diseased animals.     

Plasma pharmacokinetics and milk levels of ceftriaxone following single intravenous administration in healthy and endometritic cows

Pharmacokinetics and milk levels of ceftriaxone were studied in healthy and endometritic cows following single intravenous administration. The drug was detected up to 8 h of dosing in plasma of healthy and endometritic cows and the drug disposition followed three-compartment open model. The values of Vd_area, AUC, t_1/2β, Cl_B, MRT and P/C ratio were 0.50 ± 0.19 L.kg⁻¹, 62.2 ± 23.3 μg.ml⁻¹.h, 1.02 ± 0.07 h, 0.30 ± 0.09 L.kg⁻¹.h⁻¹, 1.55 ± 0.25 h and 0.52 ± 0.27, respectively, in healthy and 1.55 ± 0.52 L.kg⁻¹, 37.0 ± 17.1 μg.ml⁻¹.h, 1.56 ± 0.25 h, 0.56 ± 0.14 L.kg⁻¹.h⁻¹, 2.14 ± 0.34 h and 1.44 ± 0.60, respectively, in endometritic cows. The drug was detected in milk for 36 h after administration. For MIC₉₀ of 0.5 μg.ml⁻¹ the most appropriate dosage for ceftriaxone, would be 9.0 mg.kg⁻¹ repeated at 6 h intervals for the treatment of endometritis in cows.     

Comparative efficacy of bromocriptine,cabergoline and thyroxine in inducing oestrus in bitches

Forty bitches in anoestrus for more than six months from the last heat, with a serum progesterone level less than 1 ng/ml were subjected to oestrus induction trials using anti-prolactin drugs and levothyroxine, once daily orally for 20 consecutive days. The mean serum progesterone level among them was found to be 0.57 ± 0.03 ng/ml. Out of 10 animals treated in each group, five (50%) in Group I (bromocriptine @ 50 μg/kg body weight), nine (90%) in Group II (cabergoline @ 5 μg/kg body weight), eight (80%) in Group III (thyroxine @10 μg/kg body weight) and seven (70%) in Group IV (thyroxine @ 5 μg/kg body weight) responded by evincing proestrual bleeding. The mean (±SEM) time taken from initiation of treatment to onset of proestrual bleeding in Groups I, II, III and IV was 28 ± 3.39, 13.44 ± 3.12 (P < 0.05), 24.50 ± 3.18 and 33 ± 2.21 days respectively. The mean (±SEM) duration of proestrus and oestrus in the treatment groups was 9.80 ± 0.86, 10.11 ± 0.68, 11.25 ± 0.88 and 10.71 ± 0.68 days and 7.60 ± 0.24, 8 ± 0.29, 8.5 ± 0.63 and 7.85 ± 0.46 days respectively. The conception rate in relation to the number of animals responding to oestrus induction in the treatment groups was 80%, 78%, 63% and 57%, respectively. The mean (±SEM) gestation length calculated from the last breeding date and litter size in the treatment groups varied from 60.50 ± 1.55 to 64.00 ± 0.82 days and 5.14 ± 0.34 to 6.40 ± 0.40 respectively.     

Market potential for guinea fowl (<Emphasis Type="Italic">Numidia meleagris</Emphasis>) products

The survey evaluated the market potential for guinea fowl (GF; Numidia meleagris) products in the city of Harare, Zimbabwe. Questionnaires were administered to traders/producers (n = 17), retailers (n = 12), cafeteria industry (n = 33) and consumers (n = 1,680) to establish their perceptions on guinea fowl products. The average household size was 6 ± 2. Each trader sold 10 ± 6.30 keets (mean ± standard error), 33 ± 15.05 growers, 20 ± 12.69 breeders and 20 ± 10.1 crates of 30 eggs per month. Each household consumed 2.5 ± 1.39 kg of GF meat and 3 ± 0.65 dozens of GF eggs per month. Retailers purchased 52 ± 44.42 crates of GF eggs and 41 ± 30.50/kg of GF meat whilst cafeteria purchased 33.6 ± 14 crates of GF eggs and 65.5 ± 33.52 kg of GF meat per month. Growers for breeding were the major product for sale by traders (94.1%) at a price of US$7.50 ± 1.74/bird. Different industries were offering different prices for guinea fowl products because of their scarcity on the market. The mean purchase price per crate of 30 guinea fowl eggs sold to the retail and cafeteria were US$7.50 ± 1.74/bird. Different industries were offering different prices for guinea fowl products because of their scarcity on the market. The mean purchase price per crate of 30 guinea fowl eggs sold to the retail and cafeteria were US3.00 ± 0.58 and US$4.50 ± 0.50, respectively. The mean purchase prices for GF meat was lower (P < 0.05) for retailers (US$4.50 ± 0.50, respectively. The mean purchase prices for GF meat was lower (P < 0.05) for retailers (US2.5 ± 0.81/kg) than cafeteria (US$3.67 ± 0.83/kg). The challenges faced by producers in the marketing of guinea fowl products included poor supply due to the absence of good road networks to connect source areas and the market, perishability of dressed chickens due to power cuts and poor publicity. Overall, the study showed that there is greater market potential for guinea fowl products and farmers can channel their products through traders, cafeteria and retail industries.     

Ketosis in buffalo (Bubalus bubalis): clinical findings and the associated oxidative stress level

As little is known about the oxidant/antioxidant status in buffalo with ketosis, the present study was delineated to assess the oxidative stress level associated with clinical ketosis in water buffalo. A total of 91 parturient buffalo at smallholder farms were studied (61 suspected to be ketotic and 30 healthy). Clinical and biochemical investigations were carried out for each buffalo. Based on clinical findings and the level of beta-hydroxybutyrate (BHB), buffalo were allocated into ketotic (42), sublinical cases (19). Clinically, there was an association between clinical ketosis and anorexia (p < 0.001), constipation (p < 0.001), decreased milk yield (p < 0.001), ruminal stasis (p < 0.001), and loss of body condition (p < 0.01). Biochemically, in clinical ketosis compared with subclinical and control cases, there was a significant increase (p < 0.05) of BHB, malondialdehyde (MDA), nitric oxide (NO), aspartate aminotransferase (AST), L-alanine aminotransferase (ALT). However, there was a significant decrease of glucose, phosphorus, magnesium,total cholesterol and HDL-cholesterol. There was a positive correlation between BHB and MDA (r = 0.433), BHB and NO (r = 0.37), MDA and NO (r = 0.515), and Glucose and phosphorus(r = 0.521). However, there was a negative correlation between BHB and glucose (r = −0.341) and HDL and NO (r = −0.379). The result of the present study indicates that hyperketonemia in buffalo is associated with an increase of oxidative stress levels. Further studies need to be done on the efficacy of antioxidants as an ancillary treatment to relief the oxidative stress caused by ketosis.