Effect of season on estrous cycle of Yankasa sheep

An investigation was conducted to establish the effects of harmattan and hot-dry season on estrous cycle length, onset, and duration of estrus in Yankasa sheep indigenous to the Nigerian guinea savanna zone. Mean cycle lengths were 16.8 +/- 0.58 and 16.4 +/- 0.53 days during harmattan and hot-dry seasons, respectively; short cycles, 5-13 days, and long cycles, 21 to 30 days, were observed during both seasons. During the harmattan season, 57.1% of estrus began at night while 70% started at night during the hot-dry season. The duration of normal estrus observed during the harmattan, 33.6 +/- 5.87h, significantly decreased (P0.05) during the hot-dry season (24.0 +/- 5.45h). It is suggested that twice daily observation at 12-hour intervals will suffice to detect estrus in this breed of sheep.     

Ascorbic acid-induced modulation of rectal temperature fluctuations in pigs during the harmattan season

The experiment was carried out with the aim of investigating the effect of ascorbic acid (AA) on fluctuations in rectal temperature (RT) of pigs during the harmattan season. Sixteen pigs administered with AA at the dose of 250 mg/kg orally and individually served as experimental animals, and 13 others administered orally with sterile water were used as control animals. The RT was measured from all the pigs at 06:00, 13:00 and 18:00 h twice in a week for three consecutive weeks. The lowest overall mean RT value of 37.52±0.90 °C was obtained at 06:00 h in the experimental pigs, while the corresponding value in control pigs was 37.63±0.90 °C (P>0.05). The maximum RT values of 38.75±0.18 °C and 39.27±0.11 °C were recorded at 13:00 h in experimental and control pigs, respectively (P<0.05). The results indicate that AA modulates the body temperature by decreasing the maximum RT value in pigs exposed to harmattan stress, and may alleviate the risk of adverse effects of the stress on health and productivity of pigs during the cold-dry season.     

Diurnal, seasonal and sex variations in rectal temperature of African giant rats (Cricetomys gambianus, Waterhouse)

(1)

Rectal temperature (T_r) was measured in captive African giant rats (Cricetomys gambianus, Waterhouse), live-trapped in the Savannah during the harmattan, hot-dry and rainy seasons with the aim of determining diurnal, seasonal and sex patterns.

(2)

Mean (±SEM) T_r in the morning (37.16±0.04 °C) was lower (P<0.001) than the afternoon (37.49±0.03 °C) and evening (37.66±0.03 °C). There was no significant difference (P>0.05) between afternoon and evening T_r during the harmattan and rainy seasons, but the difference was significant (P<0.001) during the hot-dry season. Overall T_r was higher (P<0.001) during the hot-dry (38.03±0.03 °C) than harmattan (37.17±0.03 °C) and rainy (37.21±0.03 °C) seasons. T_r of bucks was lower than that of does (P<0.0001) during the harmattan and rainy seasons, but sex difference during the hot-dry season was not significant (P>0.05).

(3)

Base-line T_r values for the African giant rats are shown for the first time. Season, time of day and sex influence fluctuations in T_rs of African giant rats, and should be considered during diagnostic and clinical evaluations.

     

Body temperature responses of Savanna Brown goat to the harmattan and hot-dry season

Rectal and vaginal temperature responses of the Savanna Brown goat indigenous to the Nigerian guinea savanna were determined during the harmattan and the hot-dry season. Measurements were made at 06:00h and at 14:00h after 8h exposure to field conditions. At the 06:00h measurements during the harmattan, all animals were observed to shiver. A significant (P<0.01) positive correlation was found between rectal (T_re) and vaginal temperatures. During the harmattan, mean T_re was 38.2C at 06:00h and 39.7C at 14:00h; the mean difference, T_re was 1.5C. During the hot-dry season, T_re at 06:00h was 38.1C, and at 14:00h, 38.7; T_re was 0.6C. It is concluded that the harmattan is thermally more stressful than the hot-dry season and that passive thermolability may not be an important mechanism in the Savanna Brown goat in adaptation to thermal stress.     

Daily rhythms of colonic temperature and circulating blood enzymes,urea and calcium in Japanese quail (Coturnix coturnix japonica) under natural cold-dry (harmattan) and hot-dry conditions

The influence of cold-dry (harmattan) and hot-dry seasons on daily rhythmicity of colonic temperature (CT) and blood biochemical variables were investigated in 340 male Japanese quails under natural light–dark circle. Rhythm characteristics analysed using cosinor and the application of the periodic model showed a daily rhythm of CT, creatinine phosphate kinase (CPK), aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase (ALP) and urea in both seasons, while calcium did not exhibit any rhythmicity. The rhythmic parameters of mesor, amplitude and acrophase analysis showed significant (p < 0.05) effects of season. The amplitudes, except for ALP, were greater during the harmattan. The acrophase, except for CPK and urea, were all restricted to the light phase of the light-dark cycle. The results, demonstrated strong seasonal changes on the daily rhythmicity of CT and blood biochemical parameters of quails under natural light-dark circle, which could be useful for researchers, clinicians and agriculturists under different climatic conditions.     

Ameliorative effects of L-glutamine on haematological parameters in heat-stressed Red Sokoto goats

The aim of the study was to evaluate haematological responses in Red Sokoto goats (RSGs) administered with L-glutamine during the hot-dry season. Experimental animals included 28 clinically healthy RSGs divided into treated group (n = 14); each administered L-glutamine at 0.2 g/kg body weight, dissolved in 10 mL distilled water, and control group (n = 14); each administered 10 mL distilled water, per os once daily for 21 days. The ambient temperature and relative humidity recorded daily for 4 weeks were used to calculate the temperature-humidity index. Three millilitres of blood sample was collected from each goat by jugular venipuncture for haematology, while rectal temperature (RT), heart rate (HR) and respiratory rate (RR) were also measured once weekly at weeks 0 (before), 1, 2, 3 (during) and 4 (after L-glutamine administration). The haematological, RT, HR and RR data obtained weekly were analysed using repeated-measures one-way ANOVA, followed by Tukey's post-hoc test to evaluate differences between periods, and between treated and control groups. The PCV, haemoglobin concentration and RBC count were higher (P < 0.05) in the treated group compared to the control group during the period of L-glutamine administration. These differences were sustained till week 4. Beginning from week 1 of the study, the total leucocyte count in treated group (10.10 ± 0.25 × 10³/μL) was higher (P < 0.05) than the count in control group (7.23 ± 0.41 × 10³/μL), this trend was also maintained throughout the study. The neutrophil:lymphocyte ratio during weeks 3 and 4 of the experiment was lower (P < 0.05) in the treated compared to the control group. RT was lower (P < 0.05) in treated group than the control group. In conclusion, L-glutamine administration ameliorated the adverse effects of heat stress on the haematological parameters in RSGs during the hot-dry season.     

Impact of season on haematological and biochemical parameters of crossbred female calves in hot and humid tropics

The objective of the present study was to assess the impact of season on haematological and biochemical parameters of crossbred female calves. Seven crossbred female calves of 6–12 months of age were selected. The study was conducted in three different spells of 30 days each in pre-monsoon, monsoon and post-monsoon seasons. Ambient temperature (AT), relative humidity (RH) and temperature humidity index (THI) was recorded in all the three seasons. Whole blood was collected for estimation of haematological and plasma was used estimation of biochemical parameters. Highest AT and THI was recorded in pre-monsoon while highest RH was recorded in monsoon. The study revealed that season had no effect on haematological parameters such as total leucocyte, haemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, while total erythrocyte count was significantly lower in monsoon compared to pre and post-monsoon seasons. Glucose and cholesterol were significantly lower in pre-monsoon and monsoon compared to post-monsoon. Glutathione peroxidase activity was significantly higher in pre-monsoon compared to monsoon and post-monsoon. No significant difference between seasons in the concentration of total protein, albumin, globulin and albumin globulin ratio was noticed. The results indicate that hot conditions have profound effect on haematological and biochemical parameters of crossbred calves.     

Environmental profile and milk production of Friesian-Zebu crosses in Nigerian Guinea Savanna

A 10-year meteorologic data have been collated to enable delienation of the environmental profile of the Nigerian Guinea Savanna zone. Three distinct seasons are defined: a hot-dry season which lasts from March to April; a hot-humid season (May to October); and the harmattan season (November to February). The effects of these seasons on milk production by half and three-quarter Friesian-Zebu crosses were evaluated during the first 100 days of lactation over a 2-year period. There were no significant differences in milk yield between the genotypes, but at heat intensities above 27C, the half cross gave more milk than the three-quarter cross. It is thus recommended that the half Friesian-Zebu cross be selected for milk production in the Nigerian Guinea Savanna and that suitable husbandry and managerial adjustments such as provision of adequate clean water, shelter, good quality and silage and night grazing should be evolved to ameliorate the adverse effects of thermal stress and nutritional deficiency during the drier and hotter months of the year.     

Modulatory Role of Ascorbic Acid on Behavioural Responses of Pigs Transported By Road during the Harmattan Season

Experiments were performed on adult local pigs with the aim of investigating the modulatory role of ascorbic acid (AA) on their behavioural responses to 4-h, road transportation during the harmattan season. Sixteen adult pigs administered with AA at the dose of 250 mg/kg dissolve in sterile water served as experimental animals, and 13 others administered with sterile water were used as control animals. All the pigs were transported for 4-h at speed of 40-50 km/h covering a distance of 140 km. The behavioural activities were determined before and after road transportation. The behavioural activities were higher (P.     

Effects of vitamin E on diurnal variation in rectal temperature of Black Harco pullets during the hot-dry season

Experiments were performed with the aims of determining rectal temperature (RT) fluctuations in pullets, and the effect of vitamin E administration on the fluctuations during the hot-dry season. The RT values in experimental pullets administered vitamin E orally at a daily dose of 30 mg/kg, were significantly (P<0.05) lower than that of control pullets administered only water (41.21±0.02 and 41.43±0.04 °C, respectively). The dry-bulb temperature was significantly (P<0.001) and positively correlated with RT in both experimental (r=0.800) and control (r=0.936) pullets. Vitamin E administration ameliorated the heat stress of the hot-dry season, and may enhance productivity of pullets during the season.     

Behavioral and hematological responses of broiler chickens administered with betaine and ascorbic acid during hot-dry season

Heat stress is a major problem in poultry production in tropical regions. Assessing the impact of thermally stressful environmental conditions on the welfare of broiler chickens is of great importance. Behavioral responses in a novel environment and hematology of broiler chickens administered with betaine and/or ascorbic acid (AA) during the hot-dry season were evaluated. Broiler chickens were randomly divided into four groups: Group I (control) was given sterile water, Group II was given betaine, Group III was given AA, and Group IV received betaine + AA orally and daily for 42 days. An open-field test was used to assess behavior. Hematological parameters were obtained using a hematology auto-analyzer. The natural environmental conditions were predominantly outside the thermoneutral zone for broiler chickens. Results demonstrated that treated groups exhibited improved ability to adjust faster to a new environment and better hematological responses than controls, evidenced by enhanced behavioral responses, oxygen-carrying capacity, and immune responses of broiler chickens under unfavorable environmental conditions. Betaine and/or AA administration to broiler chickens improved some behavioral responses, hemoglobin concentrations, packed cell volume, and total leukocyte count during the hot-dry season.     

Haematological studies in relation to environmental temperature and different periods of breeding cycle in an air breathing fish, Heteropneustes fossilis.

Investigations were made on different haematological parameters in H. fossilis at two environmental temperature (18 degrees C and 32.5 degrees C) and different periods of breeding cycles. The RBC counts 302.0-10(4)/mm3), WBC counts (10.6-10(4)/mm3), Hb concentration (19.0g%), haematocrit (36.0%), M.C.H.C. (57.7%), total blood volumes (0.966 ml) and per cent blood volumes (1.542%) gave significantly high values but M.C.V. (119.2 micrometer3) and erythrocyte surfaces (52.96 micrometer2) gave low values at higher temperature (32.5 +/- 1 degrees C) and during breeding period (G.S.I. = 10.4 +/- 0.52 g). The higher values obtained for different haematological parameters during breeding period at high temperature may be probably related to greater physical activity and higher metabolic activity at the time of reproduction.     

The effects of air dried poultry manure on performance,organ weights and haematological measurements of weaner pigs reared in the tropics

Sixty-three Large White and Large White × Landrace pigs, initially weighing approximately 10 kg, were allocated to 9 groups of 7 pigs each with equal constant sex and breed ratios. These were fed on one of 9 diets containing 0, 5 and 10% dried poultry manure (DPM) at three levels of protein (17, 19 and 21%) for 16 weeks. Growth rate, feed intake and nutrient digestibility were measured. At the end, all animals were slaughtered, blood samples collected for haematological studies, fresh organ weights recorded and tissue and organs examined for evidence of pathological conditions. Growth rate was not significantly influenced by DPM levels but was significantly (P < 0.05) influenced by protein levels. Apparent digestibility of nutrients was not significantly influenced by protein or DPM levels. Increasing DPM levels significantly increased feed consumption and worsened feed/gain ratio. Organ weights were not significantly influenced by treatments but total white blood cells, percentage banded neutrophils, segmented neutrophils and eosinophils differed significantly (P < 0.05) among groups. The banded and segmented neutrophils were higher, while the lymphocytes were lower, than the normal values; this suggests the presence of pathogenic organisms in pigs fed on these DPM diets.     

Ventilatory threshold and mechanical efficiency in endurance runners

In order to evaluate changes in parameters at the ventilatory threshold (VT) and in mechanical efficiency (ME) during training in the years 1982 and 1983 we tested seven top-class endurance runners on a treadmill. The VT and ME were assessed during their training period (January 1982 and 1983) and during their competitive period (March and July 1982). The maximal functional variables were almost constant during the training year, the maximal change in VO2max being about 5%. Similarly, VO2 at the VT was almost constant; the maximal change in VO2 at VT was also about 5%. Substantially greater changes, about 10%, were recorded in the velocity of running at the VT, at which the maximum was attained in July (18.9 +/- 0.8 km.h-1 or 5.25 +/- 0.22 m.s-1); this value was significantly higher than values assessed during the remaining tests. The greatest change, about 23%, during the training year was found in ME, for which the maximum was attained in July (35.7% +/- 2.1%). This was not significantly different from the value recorded in March (34.5% +/- 3.3%), but both values were significantly higher than those recorded during the training period. We can therefore conclude that in highly trained endurance runners the times needed to attain the optimal conditions for sports performance differ from the point of view of special speed training and from the point of view of mechanical-metabolic readiness.     

The effect of seasons on behaviour during milking in buffaloes (Bos bubalis)

An investigation on behaviour during milking involving 200 buffaloes was carried out to study the effect of climate on milking behaviour for a period of four years. The results obtained were: (1) In extremely docile animals (temperament score I) the mean distribution was least (33.5) in hot-dry summer as compared to winter (39.2) and hot-humid summer. (2) The number of buffaloes milked after oxytocin injections was maximum (11.1%) during the hot-dry summer against other seasons for the temperament score I over temperament scores III and IV, where all buffaloes were milked with oxytocin injections. (3) The mean flow rate was least in hot-dry summer in each temperament score. (4) Milking time was higher in all the temperament scored buffaloes during the hot-dry summer than during the other seasons. It is concluded that as environmental temperature increases, there occurs an increase in thermal stress, the milking behaviour changes and animals become more hostile and excited which leads to a decrease in milk production.     

The effect of season on oocyte quality and developmental competence in Italian Mediterranean buffaloes (Bubalus bubalis)

At Italian latitudes, buffalo (Bubalus bubalis) is a seasonally polyestrous species, showing an improved reproductive efficiency when daylight decreases (autumn). The aim of the present study was to evaluate the influence of the season on buffalo oocyte recovery rate, on oocyte quality, assessed on morphological basis, and developmental competence after in vitro fertilization. For this purpose, buffalo ovaries were collected from a local abattoir and the oocytes obtained by aspirating the follicles were evaluated, classified and, if considered of good quality, devolved to the different procedures of IVEP. In general, no differences were found in terms of oocyte recovery per ovary among seasons, but interestingly, the percentage of small oocytes was higher (P<0.05) during spring and summer (0.9±0.1 and 0.9±0.2) compared to autumn and winter (0.3±0.1 and 0.2±0.1). Both cleavage and embryo rate increased during the period from October to December (71.7±3.1 and 26.5±2.1, respectively) compared to the period from April to June (58.0±2.4 and 18.8±1.6, respectively), thus reflecting the in vivo reproductive behavior. Nevertheless, it is worth emphasizing that transferrable embryos were produced in vitro, even during the unfavorable season, but with decreased efficiency. In conclusion, these results suggest to avoid the oocyte collection during spring when planning OPU trials in order to save resources and improve the benefits/costs ratio.     

Dietary analysis of young professional soccer players for 1 week during the competitive season

Limited data exist concerning the dietary practices of young professional soccer players that compete within the United Kingdom. Therefore, the purpose of this study was to investigate the nutritional and activity habits of professional male soccer players (n = 10; age: 17 ± 1 years, height: 1.72 ± 0.01 m, mass: 67.5 ± 1.8 kg, estimated maximal aerobic capacity: 57.8 ± 0.9 ml·kg·min) who played for the youth team of a UK-based Championship club. All players recorded their 7-day dietary intake and activity habits during a competitive week that included a match day, 4- training days, and 2 rest days in the first half of the 2009/2010 playing season. The intake of carbohydrates (5.9 ± 0.4 g·kg·d), proteins (1.7 ± 0.1 g·kg·d), and fats (1.5 ± 0.1 g·kg·d) represented 56 ± 1, 16 ± 1, and 31 ± 1% of the mean daily energy intake respectively. The intake of fiber was found to be significantly lower than Recommended Nutrient Intake (RNI) values (67% of RNI, p < 0.001), whereas all other analyzed micronutrients met or exceeded recommended values. A mean daily energy deficit of 788 ± 174 kcal existed because daily energy expenditures exceeded that of intake (3,618 ± 61 vs. 2831 ± 164 kcal, p = 0.001). The mean daily fluid intake was 3.2 ± 0.3 L. Consequently, the nutritional practices of the sampled group of professional youth soccer players were inadequate to sustain optimized performance throughout training and match play. Youth soccer players should therefore seek to ensure that their diets contain adequate energy through increased total caloric intake, while also optimizing the proportion of energy derived from carbohydrates and ensuring that enough fiber-rich foods are consumed.     

A seasonal study of the haematology of wild freshwater fish

Various haematological values of wild yellowfish ( Barbus holubi ), carp ( Cyprinus carpio ) and two species of mudfish ( Labeo umbratus and Labeo capensis ) were examined on a seasonal basis from May 1975-April 1976, obtained from three different localities. Haematological values of fish of different length groups (from all four species) were studied at one locality during winter only. (June 1976-August 1976). Seasonal variations were observed in all of the parameters studied but no sexual differences were found and no significant changes in the haematology could be related to breeding season. Wide individual variations were evident in fish of different length groups and no correlation existed between fish length (and mass) and haematological values.     

Foraging behaviour and prey size of the painted stork

The foraging behaviour of painted stork Mycteria leucocephala was studied during 2004–2006 at 14 different sites in the Delhi region, India. Observations were recorded on 131 individuals, including 29 juvenile birds using a video camera. Recordings were also made at the nesting colony in Delhi zoo to study the prey sizes regurgitated to nestlings. The results confirm that the painted stork is a tactile forager and exclusively piscivorous. Foraging group size ranged from 1 to 18 individuals. Per 5 min foot stirring rates in the vegetated habitats were significantly higher than in non-vegetated habitats. The attempt rate and feeding rate in the breeding season were significantly higher than that in the non-breeding season. Prey sizes taken in the breeding season were significantly smaller than those taken in the non-breeding season. About 80% fish fed to the chicks were smaller than 10 cm. Young chicks were offered smaller prey compared with older chicks. The variations in foraging parameters are discussed in relation to habitats and their conservation in the Delhi region.     

Phenotypic and genetic relationships between growth and feed intake curves and feed efficiency and amino acid requirements in the growing pig

Improvement of feed efficiency in pigs has been achieved essentially by increasing lean growth rate, which resulted in lower feed intake (FI). The objective was to evaluate the impact of strategies for improving feed efficiency on the dynamics of FI and growth in growing pigs to revisit nutrient recommendations and strategies for feed efficiency improvement. In 2010, three BWs, at 35±2, 63±9 and 107±7 kg, and daily FI during this period were recorded in three French test stations on 379 Large White and 327 French Landrace from maternal pig populations and 215 Large White from a sire population. Individual growth and FI model parameters were obtained with the InraPorc^R software and individual nutrient requirements were computed. The model parameters were explored according to feed efficiency as measured by residual feed intake (RFI) or feed conversion ratio (FCR). Animals were separated in groups of better feed efficiency (RFI⁻ or FCR⁻), medium feed efficiency and poor feed efficiency. Second, genetic relationships between feed efficiency and model parameters were estimated. Despite similar average daily gains (ADG) during the test for all RFI groups, RFI⁻ pigs had a lower initial growth rate and a higher final growth rate compared with other pigs. The same initial growth rate was found for all FCR groups, but FCR⁻ pigs had significantly higher final growth rates than other pigs, resulting in significantly different ADG. Dynamic of FI also differed between RFI or FCR groups. The calculated digestible lysine requirements, expressed in g/MJ net energy (NE), showed the same trends for RFI or FCR groups: the average requirements for the 25% most efficient animals were 13% higher than that of the 25% least efficient animals during the whole test, reaching 0.90 to 0.95 g/MJ NE at the beginning of the test, which is slightly greater than usual feed recommendations for growing pigs. Model parameters were moderately heritable (0.30±0.13 to 0.56±0.13), except for the precocity of growth (0.06±0.08). The parameter representing the quantity of feed at 50 kg BW showed a relatively high genetic correlation with RFI (0.49±0.14), and average protein deposition between 35 and 110 kg had the highest correlation with FCR (−0.76±0.08). Thus, growth and FI dynamics may be envisaged as breeding tools to improve feed efficiency. Furthermore, improvement of feed efficiency should be envisaged jointly with new feeding strategies.