Estimates of direct and maternal (co)variance components as well as genetic parameters of growth traits in Nellore sheep

In the present study, (co)variance components and genetic parameters in Nellore sheep were obtained by restricted maximum likelihood (REML) method using six different animal models with various combinations of direct and maternal genetic effects for birth weight (BW), weaning weight (WW), 6-month weight (6MW), 9-month weight (9MW) and 12-month weight (YW). Evaluated records of 2075 lambs descended from 69 sires and 478 dams over a period of 8 years (2007–2014) were collected from the Livestock Research Station, Palamaner, India. Lambing year, sex of lamb, season of lambing and parity of dam were the fixed effects in the model, and ewe weight was used as a covariate. Best model for each trait was determined by log-likelihood ratio test. Direct heritability for BW, WW, 6MW, 9MW and YW were 0.08, 0.03, 0.12, 0.16 and 0.10, respectively, and their corresponding maternal heritabilities were 0.07, 0.10, 0.09, 0.08 and 0.11. The proportions of maternal permanent environment variance to phenotypic variance (Pe²) were 0.07, 0.10, 0.07, 0.06 and 0.10 for BW, WW, 6MW, 9MW and YW, respectively. The estimates of direct genetic correlations among the growth traits were positive and ranged from 0.44(BW-WW) to 0.96(YW-9MW), and the estimates of phenotypic and environmental correlations were found to be lower than those of genetic correlations. Exclusion of maternal effects in the model resulted in biased estimates of genetic parameters in Nellore sheep. Hence, to implement optimum breeding strategies for improvement of traits in Nellore sheep, maternal effects should be considered.     

Characterization of Doayo and Kapsiki taurine cattle breeds of Cameroon in their natural environment

Data were collected on live weight (LW), heart girth (HG), height-at-withers (HW), trunk length (TL), age, sex, and coat color of 207 taurines cattle—122 of the Doayo (Namchi) breed and 85 of the Kapsiki (Kirdi) breed. The animals, aged 1 to 20 years, were selected from 60 herds randomly selected from villages of Poli of Faro and Mokolo of Tsanga, divisions of the North and Far North Regions of Cameroon. The data were analyzed using the SAS program with a linear model, applying standard tests. Results indicated no breed effect (P > 0.05) in the growth trends of LW, HG, HW, and TL. HG and TL were highly significantly (P < 0.0001) related to LW. The growth pattern for the two breeds was the same since the linear contrast of least square means for the traits at various age groups did not differ (P > 0.05) significantly. The breeds attained maturity as from 4 years. In the absence of breed effect (P > 0.05), a single regression equation was established for the estimation of live weight as thus LW = - 244.42 ( ±22.57 ) kg + 2.49 ( ±0.23 ) HG + 1.04 ( ±0.25 ) TL {\hbox{LW}} = - {244}.{42 }\left( {\pm {22}.{57}} \right){\hbox{ kg}} + {2}.{49 }\left( {\pm 0.{23}} \right){\hbox{ HG}} + {1}.0{4 }\left( {\pm 0.{25}} \right){\hbox{ TL}} , with HG contributing up to 70% of total variation and TL, 2%. This equation could be used to develop a measuring band useful in the rural environment for commercial and clinical veterinary purposes.     

Effect of supplementation of mustard oil cake on intake,digestibility and microbial protein synthesis of cattle in a straw-based diet in Bangladesh

The objective of this study was to analyse the effects of different levels of rumen-degradable protein (RDP) on intake, digestibility and microbial protein synthesis by supplementing mustard oil cake (MOC) on rice straw-based diet of cattle (Bos indicus) in Bangladesh. A 4 × 4 Latin square design was applied. Four diets having constant energy (7.0 MJ/kg of dry matter (DM)) with varying levels of RDP (M ₀ = 4.1 g/MJ (control), M ₁ = 6.3 g/MJ, M ₂ = 8.3 g/MJ and M ₃ = 12.4 g/MJ of metabolizable energy (ME)) were received by each animal for a period of 28 days. A metabolism trial was conducted for 7 days. Results indicate that with increasing levels of RDP, crude protein (CP) and RDP intake increased significantly (P < 0.01). The significant (P < 0.01) increase in digestibility values are obtained for DM, organic matter, CP and digestible organic matter in the rumen. The digestibility of neutral detergent fibre and acid detergent fibre was also increased significantly (P < 0.05). The total nitrogen (N), ammonia-N and total volatile fatty acids increase significantly (P < 0.01) while the rumen pH increased from M ₀ to M ₂ and decreased thereafter. The efficiency microbial N intake increased significantly (P < 0.01) but showed a curvilinear response with higher RDP level (12.40 g/RDP/MJ ME). This study concludes that supplementation of RDP from MOC enhances the intake, digestibility and microbial protein synthesis which ultimately increases utilization of low-quality feed resources that can be used for developing cost-effective feeding systems on a straw-based diet in tropical regions.     

Characterization of indigenous chicken production systems in Kenya

Indigenous chicken (IC) and their production systems were characterized to understand how the whole system operates for purposes of identifying threats and opportunities for holistic improvement. A survey involving 594 households was conducted in six counties with the highest population of IC in Kenya using structured questionnaires. Data on IC farmers’ management practices were collected and analysed and inbreeding levels calculated based on the effective population size. Indigenous chicken were ranked highest as a source of livestock income by households in medium- to high-potential agricultural areas, but trailed goats in arid and semi-arid areas. The production system practised was mainly low-input and small-scale free range, with mean flock size of 22.40 chickens per household. The mean effective population size was 16.02, translating to high levels of inbreeding (3.12%). Provision for food and cash income were the main reasons for raising IC, whilst high mortality due to diseases, poor nutrition, housing and marketing channels were the major constraints faced by farmers. Management strategies targeting improved healthcare, nutrition and housing require urgent mitigation measures, whilst rural access road network needs to be developed for ease of market accessibility. Sustainable genetic improvement programmes that account for farmers’ multiple objectives, market requirements and the production circumstances should be developed for a full realization of IC productivity.     

Prevalence and antimicrobial resistance profiles of <Emphasis Type="Italic">Salmonella enterica</Emphasis> serovars isolated from slaughtered cattle in Bahir Dar,Ethiopia

A study was undertaken from October 2006 to March 2007 to determine the prevalence and antimicrobial resistance patterns of Salmonella serovars. Liver, mesenteric lymph nodes, intestinal content, and carcass swab samples (each n?=?186) were collected from 186 apparently healthy slaughtered cattle at Bahir Dar abattoir. Bacteriological analysis was done according to the International Organization for Standardization (ISO 6579 2002). Isolates were serotyped at Agence Française de Securite Sanitaire des Aliments, Cedex, France. Twenty-eight isolates consisting of Salmonella Typhimurium, Salmonella Newport, Salmonella Haifa, Salmonella Heidelberg, Salmonella Infantis, and Salmonella Mishmarhaemek were identified. Salmonella Typhimurium and Salmonella Newport were most frequently isolated while Salmonella Heidelberg and Salmonella Mishmarhaemek were isolated least. Eleven of the 28 (39.3%) were resistant to one or more of the antimicrobials tested. Resistance was shown to ampicillin, chloramphenicol, gentamycin, norfloxacin, polymyxin-B, streptomycin, tetracycline, and trimethoprim. Four of 11 (36.4%) were multiple antimicrobial resistant. All the isolates tested were susceptible to the antimicrobial effects of gentamycin, norfloxacin, and trimethoprim. Eleven, four, and two isolates of the 28 were resistant to streptomycin, tetracycline, and ampicillin, respectively. All isolates of Salmonella Infantis, Salmonella Typhimurium (except one), and Salmonella Mishmarhaemek were susceptible to the tested antimicrobials. One Typhimurium isolate was resistant to chloramphenicol, streptomycin, and tetracycline. Salmonella Haifa was multiply antimicrobial resistant to ampicillin, tetracycline, and streptomycin. All isolates of Salmonella Heidelberg were resistant to streptomycin. Results of this study indicated high level of carcass contamination with antimicrobial-resistant Salmonella serovars which could pose public health risk; suggests need for hygienic slaughtering operations and proper cooking of meat before consumption. Further detailed studies involving different abattoirs, animal products, food items, and animals on different settings were recommended in the study area.     

Responses to graded replacement of urea by maize steep liquor in diets for intensively fed lambs for meat production

Urea is a common ingredient of the diets of intensively fed lambs, but is increasingly required for industrial processes. Maize steep liquor (MSL) is a by-product of maize grain degradation to produce starch that may be a suitable replacement. Fifty growing lambs were fed on equinitrogenous diets in which between 0% and 80% of the urea was replaced by MSL; their growth and metabolism were recorded over 70 days. Increasing replacement of urea by MSL increased feed intake and nutrient digestibilities, leading to increased growth rates, more efficient feed conversion, and increased nitrogen retention. Concentrations of triiodothyroxin, thyroxin, glucose, and methionine were increased by replacement of urea by liquor, and plasma urea was reduced. This study suggests that MSL is a suitable replacement for up to 80% of urea in the diet of rapidly growing lambs.     

Veterinary aspects of ecological monitoring: the natural history of emerging infectious diseases of humans,domestic animals and wildlife

Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent and its human, domestic and wild hosts is stressed.     

Growth,feed efficiency and blood profile of buffalo calves consuming high levels of fluoride

Twelve male buffalo calves of 10 to 12 months of age were divided into 3 groups of four each. They were fed wheat straw+concentrate mixture +3 Kg greens. The chemical composition of the diet was same in all the three groups except fluoride which was added (as NaF) in concentrate mixture of group B and C to make the final fluoride concentration 30 ppm and 60 ppm respectively. The animals were kept on scheduled diet for a period of 90 days. Body weights were recorded at the start of the experiment and at fortnightly interval thereafter. Analysis of data revealed that the dry matter intake decreased non significantly in group B and C as compared to control group. A significant decrease in serum calcium and a significant increase in phosphorus concentration were observed in group C animals. A significant increase was observed in alkaline phosphatase activity in group C animals. A non significant decrease was observed in T₄ values in group C animals. On the basis of these results it could be concluded that fluoride in the diet of buffalo calves @ 30 ppm is a safe level whereas 60 ppm has affected the blood metabolites.     

Proliferation and transmission patterns of <Emphasis Type="Italic">Pasteurella multocida</Emphasis> B:2 in goats

This report describes the proliferation and transmission patterns of Pasteurella multocida B:2 among stressful goats, created through dexamethasone injections. Thirty seven clinically healthy adult goats were divided into three groups consisted of 15 goats in group A, 11 goats in group B and the remaining 11 in group C. At the start of the study, all goats of group A were exposed intranasally to 1.97 × 10¹⁰ CFU/ml of live P. multocida B:2. Dexamethasone was immediately administered intramuscularly for 3 consecutive days at a dosage rate of 1 mg/kg. The exposed goats were observed for signs of HS for a period of 1 month. At the end of the 1-month period, 11 goats from group B were introduced into and commingled with the surviving goats of group A before all goats from both groups were immediately injected intramuscularly with dexamethasone for 3 consecutive days. The treatment with dexamethasone was then carried out at monthly interval throughout the 3-month study period. Goats of group C were kept separately as negative control. Three surviving goats from each group were killed at 2-week interval for a complete post-mortem examination. Two (13%) goats of group A were killed within 24 hours after intranasal exposure to P. multocida B:2 while another two (13%) goats from the same group were killed on day 40, approximately 10 days after the second dexamethasone injection. All four goats showed signs and lesions typical of haemorrhagic septicaemia. Bacteraemia was detected in 3 goats of group A that were having rectal temperature higher than 41°C. The P. multocida B:2 isolation pattern was closely associated with dexamethasone injections when significantly (p < 0.05) higher rate of isolations from both groups were observed after each dexamethasone injection. Transmission of P. multocida B:2 from goats of group A to group B was successful when P. multocida B:2 was isolated from goats of group B for a period of 28 days. There was a strong correlation between dexamethasone injections, rate of bacterial isolation and serum cortisol level. The IgG level showed an increasing trend 2 weeks after exposure to P. multocida B:2 and remained high throughout the study period.