Parameters Influencing Haematological, Serum and Bio-Chemical References in Livestock Animals under Different Management Systems

Serum bio-chemical and haematological indices constitute important panels in the diagnosis, prognosis and treatment of livestock diseases via the investigations of myriads of parameters influencing these blood and serum bio-chemical indices. Serum bio-chemical indices, haematological indices and blood electrolytes are critical physiological indices which have health implications on the diagnosis, prognosis and treatment of livestock diseases especially in animals bred under different management systems. It is important to stress that cascades of parameters of both genetic and non-genetic origin greatly have direct and in-direct health implications on serum bio-chemical indices and blood electrolytes in livestock animals and subsequently on their health/ production performances. Laboratory blood tests would be a vital tool to help detect any deviation from normal state of wellbeing in animals. Therefore, this review intends to provide base line information to establish certain haematological and serum bio-chemical indices as standard references which can be employed as alternative therapy for diagnosis, prognosis and treatment of cascades of diseases plaguing livestock animals bred under different management systems especially under the harsh condition of the tropics. Hence, it is important to establish standard values for the various blood and serum bio-chemical indices base on parameters of non-genetic origin;age, sex, physiological state, stress level, management systems, medication, health status, nutrition, hormone, climate, etc. and genetic parameters which include the breed and genotype of the animal among others obviously affect the blood and serum profile of healthy animal which subsequently influence their production performance and efficiency.

Molecular Diagnosis of Subclinical African Trypanosoma vivax Infection and Association with Physiological Indices and Serum Metabolites in Extensively Managed Goats in the Tropics

Trypanosomosis remains a major challenge to livestock production in much of tropical Sub-Saharan Africa, while diagnosis and treatment still depend on inefficient parasitological techniques. Endemic infections depend on animal reservoirs with subclinical parasitemia. We report molecular diagnosis of subclinical Trypanosoma vivax (T. vivax) infection using polymerase chain reaction (PCR) for the first time in Nigerian goats and associate parasite presence with gross physiological traits and serum metabolites in extensively managed Nigerian goats. PCR was used to amplify a 400 bp DNA fragment of the parasite genome in 205 goats across three geographical zones of the country. Results showed a high subclinical infection rate (SCIR) of 71.7% in the total goats examined. Overall SCIRs of 71%, 75.9% and 55.6% were recorded in West African Dwarf, Red Sokoto and Sahel goats respectively, while geographical SCIRs were 71.2% (Southwest), 75% (Northwest) and 70% (Northeast). T. vivax presence had significant (P 0.05) effect on respiratory rate and is associated with higher creatinine levels in sera. Logistic regression analyses with Hosmer-Lemeshow goodness-of-fit showed that respiratory rate is the most important predictive trait for the presence of T. vivax infection (P 0.05). Goats appear to be a viable reservoir for T. vivax infection of other livestock. Molecular diagnosis of subclinical trypanosomosis using PCR could be useful for large scale epidemiological studies, early diagnosis of subclinical infection and treatment of the disease in extensively managed tropical goats.

Effects of coat colour genes on body measurements, heat tolerance traits and haematological parameters in West African Dwarf sheep

With 178 West African Dwarf sheep aged 1 to 3 years, a study was conducted to investigate the effects of coat colour genes on body measurements, heat tolerance traits and haematological parameters. Body measurements considered included body length, hair length, ear length, hip width, tail length, height at withers, rump height, fore cannon bone length, chest depth, heart girth and body weight. Heat tolerance traits considered were skin temperature, rectal temperature, pulse rate and respiratory rate. Blood samples were collected for the evaluation of white blood cell (WBC), red blood cell (RBC), haemoglobin (HGB), haematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin cell (MCHC), red cell distribution width (RDW), platelets (PLT), mean platelets volume (MPV), platelets distribution width (PDW) and plateletcrits (PCT). Results showed that coat colour gene (CCG) had significant (P < 0.01) effect on rump height and tail length. Animals with black (BB) coat colour had the highest mean value for rump height (57.80 ± 1.29 cm) and tail length (22.10 ± 0.89 cm), while brown (Bb) coat colour had the least value of 53.00 ± 6.00 cm for rump height and 17.50 ± 0.50 cm for tail length. The CCG had significant (P < 0.01) effect on body temperature and pulse rate, with the grey/mouflon (Ag) colour possessing the highest body temperature (38.90°C ± 0.22°C), and Bb having the least value of 37.20°C ± 0.35°C. White/tan (Awt) had the highest pulse rate of 28.90 ± 0.66 beats/min and Bb had the least value of 20.00 ± 2.00 beats/min. The CCG had significant (P < 0.01) effect on RBC and MPV with brown (Bb) colour having the highest RBC counts (18.20 ± 0.00 L) and badgerface (Ab) having the least value (11.50 ± 0.62 L). The Bb had the highest value (5.60 ± 0.00 fL) for MPV and Ab had the least value (4.70 ± 0.15 fL). Sheep with Bb and Ab were found to withstand heat stress better than others.