Status of Lipid Peroxidation,Some Antioxidant Enzymes and Erythrocytic Fragility of Crossbred Cattle Naturally Infected with <Emphasis Type="Italic">Theileria annulata</Emphasis>

Erythrocytic lipid peroxidation, activities of some antioxidant enzymes and osmotic fragility of red blood cells was studied in adult (>1 year) crossbred cattle naturally infected with Theileria annulata. Twenty clinically healthy animals (group I) and 15 clinical cases (group II) of tropical theileriosis were selected. Cattle suffering from theileriosis had significantly higher (p<0.01) erythrocytic lipid peroxidation and osmotic fragility. Activities of antioxidant enzymes, viz. glucose-6-phosphate dehydrogenase (G6PD) and glutamate peroxidase (GPx) were also significantly increased (p<0.01) in group II. However, superoxide dismutase and catalase did not show significant changes. The results indicated that infection with theileria led to increased oxidative stress to the animals, and even a significant rise in the activities of antioxidant enzymes. G6PD and GPx could not lower this oxidative stress. However, the increase in the activities of antioxidant enzymes pointed towards the body’s defence mechanism against lipid peroxidation during oxidative stress in theileriosis.     

Evaluation of organ function and oxidant/antioxidant status in goats with sarcoptic mange

The objective of the present study was to investigate the hemato-biochemical changes and status of oxidative stress in goats with scabies infection. The study was conducted on 12 Jamunapari goats; six clinically infected with scabies (group I) and six healthy goats as control (group II). The examination of skin scraping revealed the presence of Sarcoptes scabiei in the infected group. In hemato-biochemical indicators, hemoglobin%, packed cell volume, total erythrocyte count, albumin and albumin: globulin ratio decreased whereas, globulin, alanine aminotransferase, bilirubin, creatinine, and blood urea nitrogen increased significantly (p < 0.05) in group I animals as compared to group II healthy goats. Among the oxidative stress indices, plasma nitrate and erythrocytic lipid peroxidation were increased and reduced glutathione levels decreased significantly (p < 0.05) in group I goats as compared to group II healthy goats. The results of the present study suggest that scabies infection alters the hemato-biochemical indicators, increases oxidative stress and decreases antioxidant status in goat.     

Effects of breed type and age at first calving on length of productive life in a cow–calf system in Southeastern Mexico

The effect of age at first calving (AFC) and breed type (BG) on cow length of productive life in the herd (LPL) and cumulative kilograms of calves weaned per cow (KWC) was studied. Data on 313 Brahman, 183 Nellore, and 269 crossbred cows (undefined crosses of European × Zebu cattle) born from 1986 to 2002 were used. Three hundred and ninety-one out of the 765 cows had non-censored data. LPL curves by BG and AFC (<2.5, 2.5 to <3, 3 to <3.5, and ≥3.5 years of age) were obtained using life table procedures. The magnitude of the effect of AFC and BG on LPL was determined using Cox proportional hazard regression procedures. KWC data (n = 359) were analyzed by a linear model that included the effects of period of birth of the cow (in years), BG, and AFC. There was no difference in the survival curves between BG (p > 0.05), but there was for the hazard ratio of culling (p < 0.05). Brahman and Nellore cows produced more kilograms of calves (p < 0.05) than crossbred cows. AFC influenced LPL (p = 0.014) and KWC (p = 0.012). Cows with AFC <3 years of age stayed longer in the herd and weaned more KWC than those with a higher AFC (p < 0.05).     

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.     

Acute kidney injury mediated by oxidative stress in Egyptian horses with exertional rhabdomyolysis

The present study was carried out to evaluate the role of oxidative stress in the pathophysiologic process of acute renal failure associated with exertional rhabdomyolysis (ER) in Egyptian horses. ER was tentatively diagnosed in 31 Baladi horses based on case history, physical examination findings and confirmed by elevation of plasma creatine kinase (CK) and urine myoglobin concentrations. According to severity of the condition, the diseased horses were categorized into two main groups; the first group included 18 horses with minimal clinical signs and plasma CK <60 000 IU/L; whereas, the second group included 13 horses with overt clinical signs and plasma CK >100 000 IU/L). It was found that plasma creatol (CTL) was positively correlated (p < 0.01) with plasma malondialdehyde (MDA) (r = 0.775), nitric oxide (NO) (r = 0.768), methyguanididne (MG) (r = 0.995), CK (r = 0.768), urine glucose (r = 0.778), urine protein (r = 0.767), renal failure index (RFI) (r = 0.814) and urine sodium (r = 0.799) and negatively correlated (p < 0.01) with total antioxidant capacity (TAC) (r = −0.795), superoxide dismutase (SOD) (r = −0.815), glutathione peroxidase (GSH-Px) (r = −0.675), Vitamin C (r = −0.830), urine creatinine (r = −0.800), urine/plasma creatinine ratio (r = −0.827) and urine/plasma urea ratio (r = −0.807). The correlation between these biochemical variables might suggest a possible role of oxidative stress in renal injury associated with severe rhabdomyolysis in horses. It is suggested that exaggeration of oxidative stress associated with increased muscle membrane leakage plays a key role in acute kidney injury in Baladi horses with severe rhabdomyolysis.     

Erythrocyte Lipid Peroxides and Blood Zinc and Copper Concentrations in Acute Undifferentiated Diarrhoea in Calves

Undifferentiated acute calf diarrhoea is a major concern for the dairy industry and its aetiopathogenesis remains diverse. The present study aimed to examine the role of oxidative stress through estimation of erythrocyte lipid peroxide levels and blood zinc and copper concentrations using natural cases of diarrhoea in calves aged 15–30 days old. The calves were kept under identical managemental conditions and were provided with pooled whole colostrum during the first three days and thereafter with only whole milk until they were 1 month old. Diarrhoeic (n = 11) and normal calves (n = 11) of the same age group (15–30 days old) were randomly selected from an organized dairy farm for the study. The mean blood zinc concentration (50.01±2.45 μmol/L vs 66.06±3.06 μmol/L) was significantly (p < 0.05) lower and copper concentration was significantly (p < 0.05) higher in diarrhoeic calves (12.90±0.31 μmol/L vs. 9.44±0.16 μmol/L) than in the healthy calves. The erythrocyte lipid peroxides level was higher (p < 0.05) in diarrhoeic calves (6.88±0.23 nmol malondialdehyde (MDA) per mg of haemoglobin (Hb)) than healthy calves (6.27±0.07 nmol MDA per mg Hb). From the results of the study it is concluded that oxidative stress and antioxidant minerals (zinc and copper) might play important roles in the aetiopathogenesis of bovine calf diarrhoea.     

Sweet potato and Green panic as sole fodder for stall-fed lactating White Fulani cows and growing calves

Three sweet potato varieties (TIS-87/0087; TIS-8164; TIS-2532.OP.1.13) and Green panic (Panicum maximum) were evaluated for forage quality in a completely randomized design (CRD) using 12 sole-fed lactating White Fulani cows for 21 days, and 12 growing White Fulani and White Fulani x Brown Swiss calves for 77 days. Dry matter intake of cows ranged (p < 0.05) between 131 g/W_kg ^0.734 in TIS-87/0087 and 152 g/W_kg ^0.734 in TIS-8164. Daily milk yields increased (p < 0.05) in TIS-87/0087 (2%) and TIS-8164 (5%), but decreased in TIS-2532.OP.1.13 (5%) and Green panic (19%). Mean (±SEM) milk total solids (13.16 ± 0.05 g/100 g), ash (0.78 ± 0.01 g/100 g), protein (3.79 ± 0.07 g/100 g), fat (3.98 ± 0.06 g/100 g), and lactose (4.62 ± 0.14 g/100 g) were significantly different (p < 0.05) among treatments. The White Fulani x Brown Swiss calves recorded about 10, 25 and 29% higher birthweight, milk intake and bodyweight gains respectively, but about 3% lower dry matter intake than the purebred White Fulani calves. The rumen degradation rates were similar (p > 0.05), while the rest rumen dry matter degradation characteristics were lowest (p < 0.05) for Green panic. Sweet potato forage could be used as sole feed or supplement for dry-season Green panic.     

Oxidative stress indices in the erythrocytes from lactating cows after treatment for subclinical ketosis with antioxidant incorporated in the therapeutic regime

The present investigation was carried out to assess the erythrocytic oxidative stress indices such as lipid peroxides level and activities of antioxidant enzymes such as superoxide dismutase and catalase, and some hematological parameters after treatment of subclinically ketotic lactating cows with antioxidants, vitamin E and selenium, incorporated in conventional treatment regimen. The study was carried out using lactating cows reared in small dairy herds in and around Bhubaneswar. Out of 250 urine samples examined, 42 cows were diagnosed positive for subclinical ketosis with an overall incidence of 16.8%. Blood samples were collected on day 0 (before treatment) and treatment was initiated on day 1 and the second sampling was carried out on day 7. The hematological parameters improved significantly following treatment as compared to pre-treatment level (day 0). A significant (P < 0.05) improvement was observed on day 7 with respect to hemoglobin level (8.66 ± 0.23 vs. 9.12 ± 0.14 gm/dl) and packed cell volume (29.7 ± 0.56 vs. 31.1 ± 0.50%) in the group given routine treatment along with antioxidants. The comparison of mean lipid peroxides level before (day 0) and after treatment (day 7) revealed a significant difference in group I (routine treatment, P < 0.05) and group II (routine treatment plus antioxidants, P < 0.01). The maximum reduction in SOD activity was recorded in group II animals after treatment with conventional regimes along with supplemented antioxidants (1.29 ± 0.08 against 1.89 ± 0.15 units/ mg of Hb, P < 0.01). The mean value of SOD activity recorded in group III animals kept as non-treated positive control (PC) on day 7 (2.59 ± 0.14 units/mg of Hb) was significantly (P < 0.05) higher than the mean level recorded on day 0 (1.91 ± 0.31 units/mg of Hb). An almost similar trend was observed in erythrocytic catalase activity where there was a significant (P < 0.05) reduction in catalase activity in the group II (RT+A) but there was no significant increase in catalase activity in non-treated positive control (PC) animals.     

Milk yield estimation of Ogaden cattle breed based on methods of weigh–suckle–weigh and calves’ growth

Daily milk yield of Ogaden cattle was estimated from milk suckled by 269 calves born and maintained between 1994 and 2004 at Haramaya University Beef Farm, Ethiopia. The weigh–suckle–weigh method and the growth of calves were used to estimate the yield. Mean predicted daily milk yield of the breed based on the weigh–suckle–weigh method was 4.39 ± 0.03 kg day⁻¹. Daily milk yield estimated from the growth of calves up to 3 months of age was 4.59 ± 1.43 kg day⁻¹. The milk yield was significantly affected by seasons of calving (p < 0.001), parities of the dams (p < 0.05), weeks of lactation (p < 0.001) and birth weights of calves (p < 0.05). A relatively higher milk yield was observed from cows calved during the long rain season. A higher milk yield was produced by cows in fifth parity. Heavier calves at birth suckled more milk than lighter calves. Daily milk yield was significantly higher in 3–6 weeks of lactation. The result of this study indicated that the milk yield produced by Ogaden breed was relatively higher than the yield of some Zebu breed measured by partial suckling system in Ethiopia and was comparable to the yield from Zebu cattle in the tropics estimated by the same method.     

Growth performances of F1 angus plus calves grazing on pasture in Hawaii’s tropical climate

Angus Plus cattle offer advantages for heat tolerance and forage utilization by introduction of Brangus and Brahman to Angus. To evaluate its adaptability in Hawaii Islands, we reported the growth performances of 213 F1 Angus Plus calve grazing on pasture. Least-square means of pre-weaning ADG ranged from 1,087 to 1,167 g in bull calves and from 1,030 to 1,048 g in heifer calves. The 205 d-adjusted weaning weight were 226 to 285 kg in bulls and 214 to 252 kg in heifers. The birth weight and hip height at birth were significantly correlated with weaning weight, 205 d-adjusted weaning weight, hip height at weaning and pre-weaning ADG (P < 0.01). Sire group significantly influenced pre-weaning growth performances through interaction with sex of calf. Bull calves from sire group of high growth were 1.0–3.8 kg heavier in birth weight than the bull calves from other sires (P < 0.001). Sire group x sex interaction was significant (P < 0.05) for calf birth weight, 205-d adjusted weaning weight and pre-weaning ADG. Sire group also played a significant role in hip height at birth (P < 0.05). Selections of the sires preferable for growth significantly improved calf pre-weaning growth performances.     

Effects of feeding different dietary protein and energy levels on the performance of 12–15-month-old buffalo calves

The study investigated the performance response of different dietary protein and energy levels of Nili-Ravi buffalo calves. Sixty buffalo calves of 12–15 months of age and similar body weight (140 ± 14 kg) were divided in to 12 groups, five animals in each group, according to 4 × 3 factorial arrangements. Twelve rations were formulated containing four levels of crude protein (CP; 10.5%, 12.20%, 13.80%, and 15.55%) each with three levels (1.72, 2.11, and 2.5 Mcal/Kg) of metabolizable energy (ME). Experiment lasted for 100 days; first 10 days were given for dietary adaptation. Daily feed consumption in calves fed all experimental diets were statistically significant (p < 0.05) across all treatments. Higher feed intake was observed in buffalo calves fed diets containing 12.20% and 13.85% CP with 2.11 Mcal/kg ME. Results of dry matter (DM) digestion were significantly different (p < 0.05) across all treatments. There was a quadratic (p < 0.05) response of DM digestibility for levels of dietary protein while, curvilinear (p < 0.05) trend with respect to dietary energy levels. Daily weight gain of buffalo calves did not show any treatment effect. The outcome of the present study indicate that 12–15-month-old buffalo calves perform adequately well when fed on diets containing 12.2% CP and 2.10 ME Mcal/Kg.     

Studies on correlations among parasitaemia and some hemolytic indices in two tropical diseases (theileriosis and anaplasmosis) in Fars province of Iran

This study was carried out in two observational clinical studies. Study 1 comprised 50 adult crossbred cattle naturally infected by Theileria annulata. Infected animals were divided into 4 subgroups with different parasitaemia (<1%, 1–3%, 3–5% and >5%). Study 2 comprised 20 adult crossbred cattle naturally infected by Anaplasma marginale. Infected animals were divided into 3 subgroups with different parasitaemia (<10%, 10–20% and 20–30%). In study 1, a significant negative correlation (P < 0.001) was observed between parasitaemia and superoxide dismutase (SOD). Positive correlations (P < 0.001) were observed between parasitaemia and lactate dehydrogenase (LDH) and mean corpuscular fragility (MCF). In study 2 positive correlations (P < 0.05) were observed among parasitaemia and MCF and LDH activity. SOD activity had a negative correlation with parasitaemia in cattle with parasitaemia lower than 10% but no significant correlation (P > 0.05) was observed between SOD activity and parasitaemia in cattle with 10–20 and 20–30% parasitaemia. In comparison of both studies we came to the conclusion that in theileriosis as the severity of disease increased the anaemia, MCF and LDH activity increased and SOD activity decreased at any parasitaemia, but in anaplasmosis the anaemia, MCF and LDH activity increased at any parasitaemia but SOD activity decreased only in early but not in advanced stages of disease.     

Effect of restricted suckling on milk yield,milk composition and udder health in cows and behaviour and weight gain in calves,in dual-purpose cattle in the tropics

The study was conducted to evaluate the effects of restricted suckling (RS) in dual-purpose cows and calves compared to artificial rearing (AR). Twelve Holstein-Zebu cows with calves were assigned to each treatment. Cows were milked once daily in the morning with calves present to stimulate milk let-down. RS calves suckled 30 min after milking and 30 min in the afternoon, whereas AR calves were milk-fed from nipple bottles. The daily saleable milk yield was higher in RS than in AR cows (p < 0.01; 7.44 vs 6.50 kg/day), whereas RS cows had lower milk-fat content (p < 0.001). AR cows had higher California Mastitis Test scores (p < 0.001) and lower lactose content (p < 0.001) compared to RS cows, which indicates an improved udder health in RS cows. AR calves displayed more ‘cross-suck’ during suckling/milk feeding (p < 0.001) and during observations of general behaviour (p < 0.05), and more ‘lick and sniff interior’ during milking (p < 0.05) and suckling/milk feeding (p < 0.01), compared to RS calves. During observations of general behaviour the RS calves were more often observed to ‘walk’ (p < 0.01) and ‘lick self’ (p < 0.05) and less frequently to ‘eat concentrate’ (p < 0.05) than AR calves. Results support the hypothesis that RS increases milk yield, influences milk composition and improves udder health in cows, and decreases abnormal sucking in calves.     

Milk yield and reproductive performance of dairy cattle under smallholder management system in North-eastern Amhara Region,Ethiopia

This study was conducted in South Wollo Zone of Amhara Regional State, Ethiopia, to assess the milk yield and reproductive performance of indigenous and crossbred cattle under smallholder management conditions. Questionnaire survey was used to collect retrospective data on the performance of dairy cattle in 186 households. Thirty two postpartum cows (16 indigenous and 16 crossbred) were selected purposively and monitored for five months and milk samples were collected twice per week from each cow to determine postpartum ovarian activity using ELISA techniques. Daily milk yields at all stages of lactation were significantly (P < 0.01) higher in crossbred than indigenous cows. Crossbred cows had significantly (P < 0.01) longer lactation length and shorter age at first calving, while calving interval was significantly shorter in cows that gave previous calves during the wet season than the dry season. Only six cows (18.8%) showed heat signs on an average of 136 days postpartum of which one was a crossbred and five were indigenous. While, 11 cows (34.3%) resumed ovarian activity until 150^th day postpartum among which three were crossbred and eight were indigenous.     

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.     

Ameliorative effects of boron on serum profile in buffalo (Bubalus bubalis) fed high fluoride ration

An experiment was undertaken to evaluate the protective role of boron on the serum profile of buffalo calves fed a high fluoride ration. Twelve male Murrah buffalo (Bubalus bubalis) calves of 6–8 months age, divided into three groups of four calves in each, were fed basal diets and supplemented with sodium fluoride (NaF, 60 ppm) alone or in combination with borax (Na₂B₄O₇.10H₂O, 140 ppm) for 90 days. Boron (B) was added in the ration as borax to make @140 ppm boron (elemental B) on DM basis in treatment II. Dietary F caused a significant (p < 0.05) depressing effect on serum Ca and Zn on day 90 which was improved with B supplementation. However, serum Fe and Cu did not show any significant change on F or F+B supplementation. The serum ALP and phosphorus level were increased significantly (p < 0.05) on F feeding but declined significantly (p < 0.05) when B was fed. The findings suggested beneficial effect of boron on serum minerals and ALP in buffalo calves fed high fluoride ration.     

Fertility in Holstein × Gyr cows in a subtropical environment after insemination with Gyr sex-sorted semen

Breeding records, including 649 inseminations during fall and winter at a dairy farm in a subtropical area of Western Mexico (24o N; 24°C, mean annual temperature 24°C) were analyzed to document effects of sex-sorted semen from commercial Gyr bullls, estrus synchronization protocol, inseminator, sire and environmental conditions on fertility of crossbred cows (Holstein × Gyr). Percentage of services resulting in pregnancies decreased sharply when sex-sorted semen was used (22.7 vs. 37.7%; P < 0.01). Although statistically not significant (P = 0.31), cows whose first insemination was in November experienced a numerically greater reduction (21 percentage points) in pregnancy rate compared to cows whose first insemination occurred in December. Substantial increases in services per pregnancy (4.71 ± 1.35 vs. 2.13–2.43; P < 0.01) were associated with the warmer month of the study period, November, compared to other winter months. Pregnancy rates of cows regardless of semen category (33%) were not affected by sire, temperature–humidity index and estrus synchronization protocol. Cows inseminated by one inseminator had higher pregnancy rates (P < 0.01) than cows inseminated by other two technicians. The sorted sperm produced 91% (142/156) female offspring. It was concluded that, under the field conditions of the present study, pregnancy rate with sexed semen was 15 percentage points lower than pregnancy rates using conventional semen, with 91% of female calves derived from sexed sperm.     

The effect of dietary garlic supplementation on body weight gain,feed intake,feed conversion efficiency,faecal score,faecal coliform count and feeding cost in crossbred dairy calves

Thirty-six crossbred calves (Holstein cross) of 5 days of age were used to study the effect of garlic extract feeding on their performance up to the age of 2 months (pre-ruminant stage). They were randomly allotted into treatment and control groups (18 numbers in each group). Performance was evaluated by measuring average body weight (BW) gain, feed intake (dry matter (DM), total digestible nutrient (TDN) and crude protein (CP)), feed conversion efficiency (FCE; DM, TDN and CP), faecal score, faecal coliform count and feeding cost. Diets were the same for the both groups. In addition, treatment group received garlic extract supplementation at 250 mg/kg BW per day per calf. Body weight measured weekly, feed intake measured twice daily, proximate analysis of feeds and fodders analysed weekly, faecal scores monitored daily and faecal coliform count done weekly. There was significant increase in average body weight gain, feed intake and FCE and significant decrease in severity of scours as measured by faecal score and faecal coliform count in the treatment group compared to the control group (P < 0.01). Feed cost per kilogramme BW gain was significantly lower in the treatment group compared to control group (P < 0.01). The results suggest that garlic extract can be supplemented to the calves for better performance.     

Response of Nkedi Zebu and Ankole cattle to tick infestation and natural tick-borne,helminth and trypanosome infections in Uganda

A cross-sectional study was conducted in Soroti district of Uganda to establish important traits of Nkedi Zebu and Ankole cattle regarding their production performance responses to natural infections of trypanosomes, gastrointestinal nematodes, Theileria parva, Babesia bigemina, Anaplasma marginale and tick infestations. Over four visits between October 2006 to August 2007, tick counts were performed and blood, faecal samples and sera were collected from the Nkedi Zebu (295) and Ankole (165) cattle from 86 herds in six locations per visit. Low parasitological prevalence of trypanosome infection (<6%) and high prevalence of gastrointestinal nematode infections (>30%) with low faecal egg counts (110–300 eggs per gramme (EPG)) were observed in the Nkedi Zebu and Ankole cattle. Both breeds had high, moderate and low mean counts of Rhipicephalus appendiculatus (18.0–24.0), Rhipecephalus (Boophilus) decoloratus (3.6–10.3) and Amblyomma variegatum ticks (1.7–4.3), respectively. In addition, both breeds had similar mean packed cell volumes (26.4–31.2) and a similar percentage of animals were anaemic (14.5–36.6%). The Nkedi Zebu cattle further had higher mean optical density (OD) values for antibodies against T. parva (1.093–1.445) and A. marginale infections (0.573–0.583), and significantly (P < 0.001) higher mean OD values of antibodies against B. bigemina infections (1.07–2.175) than the Ankole cattle: T. parva (1.030–1.302); A. marginale (0.442–0.603) and B. bigemina infections (0.863–2.154). The Ankole cows produced significantly more (P < 0.001) milk per day (2.68 L) than the Nkedi Zebu cows (1.98 L), and the Ankole oxen had significantly higher (P < 0.05) draught power output (2.57 days/acre) than the Nkedi Zebu oxen (2.93 days/acre). Liveweights of calves aged 0–12 months of both breeds were comparable, suggesting that the Nkedi Zebu and Ankole cattle under similar disease challenge exhibited similar growth rates. In conclusion, the Nkedi Zebu cattle seem to possess a higher degree of disease resistance against endemic parasitic diseases, while the Ankole cattle seem to possess a moderate degree of disease resistance coupled with a moderate production potential.     

Growth performance and carcass characteristics of indigenous Mukota pigs of Zimbabwe

Carcass quality characteristics are essential in affecting grading and revenue that pig producers realize. No information is available on the grading of carcasses in indigenous Mukota pigs of Zimbabwe. The objective of this study was to determine the influence of genotype (Mukota and Large White × Mukota) and sex on post-weaning growth performance and carcass traits of pigs fed maize cob-based diets. All pigs were weighed at 2-week intervals to estimate average daily gain, dressing percentage (DP), and carcass lengths. Backfat thickness was also measured. Males had higher body weight gains than females (P < 0.05). Growth rates for Mukota (0.31 ± 0.010) and crossbred (0.41 ± 0.030) pigs were lower in the cool season than the other seasons (P < 0.05). Body weights were consistently higher in the crossbred than in the Mukota pigs (P < 0.05). Mukota pigs showed a peak growth between 12 and 14 weeks post-weaning (P < 0.05). The DPs were 0.70 and 0.73 for the Mukota and crossbred pigs, respectively (P < 0.05). Crossbred pigs had longer (P < 0.05) carcasses than Mukota (655.5 ± 1.68 versus 507.2 ± 0.92 mm). Although there were no differences in the backfat thickness between males and females of the crossbred pigs, Mukota males had thicker backfat than the females (P < 0.05). Crossbreeding is, therefore, significant in improving carcass grades of Mukota pigs.