Ndazo Salka Minka

Influence of cold–dry (harmattan) season on colonic temperature and the development of pulmonary hypertension in broiler chickens, and the modulating effect of ascorbic acid

License. The full terms of the License are available at http://creativecommons.org/licenses/by-nc/3.0/. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. Permissions beyond the scope of the License are administered by Dove Medical Press Limited. Information on how to request permission may be found at: http://www.dovepress.com/permissions.php Open Access Animal Physiology 2014:6 1–11 Open Access Animal Physiology Dovepress

Effects of Cold-Dry (Harmattan) and Hot-Dry Seasons on Daily Rhythms of Rectal and Body Surface Temperatures in Sheep and Goats in a Natural Tropical Environment

Studies on daily rhythmicity in livestock under natural conditions are limited, and there is mounting evidence that rhythm patterns differ between chronobiological studies conducted in the laboratory and studies conducted under pronounced natural seasonality. Here, we investigated the influence of cold-dry (harmattan) and hot-dry seasons on daily rhythmicity of rectal (RT) and body surface temperatures (BST) in indigenous sheep and goats under natural light-dark cycles. The RT and BST of the animals, and the ambient temperature (AT) and relative humidity (RH) inside the pen, were measured every three hours for a period of two days, twice on separate days during the hot-dry and the harmattan seasons, respectively. The AT and RH had minimum values of 16°C and 15% recorded during the harmattan and maximum values of 32°C and 46% recorded during the hot-dry season, respectively. A trigonometric statistical model was applied to characterize the main rhythmic parameters according to the single cosinor procedure. The result showed that RT and BST exhibited different degrees of daily rhythmicity, and their oscillatory patterns differed with the seasons (larger amplitude during the harmattan season than during the hot-dry season). The goats displayed greater (p < 0.05) amplitude of BST than the sheep in all seasons. The acrophases were restricted to the light phase of the light-dark cycle. The mesor of RT in goats was not affected by the season, but mesors of BST in both species were significantly higher (p < 0.05) during the hot-dry than the harmattan season. The goats had a more robust RT rhythm (70%) as compared to the sheep (56%). Overall, the results demonstrated that seasonal changes influenced considerably the daily rhythmicity of RT and BST in sheep and goats under natural light-dark cycle. Awareness of these changes may be useful in the improvement of diagnosis, treatment and prevention of diseases, and welfare and productivity of sheep and goats under cold-dry and hot-dry conditions.

Effects of Antioxidants Vitamin E and C on ErythrocyteFragility, HaemoglobinIndex and Colonic Temperature of Transported Japanese Quails ( Coturnixcoturnix japonica )

The present study investigated the effects of antioxidants Vitamin E (VE) and C (ascorbic acid, AA) on erythrocytes osmotic fragility (EOF), haemoglobin index (HI), colonic temperature (CT) and recovery times of transported Japanese quails during the hot-dry conditions. Two hundred male Japanese quails were used. The birds were randomly and equally divided into four groups: VE and AA groups, administered with 0.5 mg/kg and 200 mg/ kg body weight of VE and AA, respectively, control transported group (control group), administered with 0.5 ml of sterile water, and sedentary non-transported group (S). One hour after the administration of the antioxidants, the birds were transported by road for 2 h. The EOF, HI and CT were recorded before transportation, immediately after transportation (0) and on 3rd and 7th day of post-transportation period. The results showed that transportation induced hyperthermia, increased EOF and hypochromic erythrocytes in the quails, the effects of which were mitigated by antioxidants VE and AA. Base-line values for EOF were returned to normal in the control, AA and VE quails on days 7, 3 and 0, respectively post-transportation. The findings showed that recovery time after transportation in quails should be 7 days; but the duration may be reduced to 3 days if treated with AA or eliminated completely if the quails are treated with VE before transportation. The ameliorating effect was more pronounced in quails administered with antioxidant VE. The EOF may be employed as a biomarker and additional diagnostic tool for the assessment of transport-induce oxidative stress in quails.

Daily rhythms of cloacal temperature in broiler chickens of different age groups administered with zinc gluconate and probiotic during the hot‐dry season

The aim of the experiment was to evaluate effects of zinc gluconate (ZnGlu) and probiotic administration on the daily rhythm of cloacal temperature (tcloacal) in broiler chickens of different age groups during the hot‐dry season. One‐day‐old broiler chicks (n = 60) were divided into groups I–IV of 15 chicks per group, and treated for 35 days: Group I (control) was given deionized water; Group II, ZnGlu (50 mg/kg); Group III, probiotic (4.125 × 106 cfu/100 mL), and Group IV, ZnGlu (50 mg/kg) + probiotic (4.125 × 106 cfu/100 mL). Air dry‐bulb temperature (tdb), relative humidity (RH), and temperature‐humidity index (THI) inside the pen, and tcloacal of each broiler chick were obtained bihourly over a 24‐h period; on days 21, 28, and 35 of the study. Values of tdb (32.10 ± 0.49°C), RH (49.94 ± 1.91%), and THI (38.85 ± 0.42) obtained were outside the thermoneutral zone for broiler chickens, and suggested that the birds were subjected to heat stress. Application of the periodic model showed disruption of daily rhythm of tcloacal in broilers on day 21, which was synchronized by probiotic administration. The administration of probiotics or ZnGlu + probiotics to a greater extent decreased the mesor and amplitude, delayed the acrophases of tcloacal in broilers, especially at day 35, as compared to the controls. Overall, the tcloacal values in broiler chickens administered with probiotic alone (41.25 ± 0.05°C) and ZnGlu + probiotic (41.52 ± 0.05°C) were lower (P < 0.001) than that of the controls (41.94 ± 0.06°C). In conclusion, probiotic alone synchronized tcloacal of the birds at day 21, and, in addition, decreased tcloacal response most, followed by its coadministration with ZnGlu, the antioxidants may be beneficial in modulating daily rhythmicity of tcloacal and alleviating adverse effects of heat stress on broiler chickens during the hot‐dry season.

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

Abstract 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.

Modulating Effect of Ascorbic Acid on Transport-Induced Immunosuppression in Goats

The effect of 12 h road transportation on some basic blood cells and the modulating role of ascorbic acid were investigated in 40 adult Red Sokoto goats during the hot dry season. The animals were divided into two groups, GI (experimental; n = 20) and GII (control; n = 20). Group 1 was administered with ascorbic acid (AA) per os at a dosage rate of 100 mg/kg body weight, while GII was given 10 mL of sterile water per goat. Forty minutes after the administration and loading, the goats were transported for 12 h. The result obtained in GII goats showed that loading, transportation, high ambient temperature (AT), and relative humidity (RH) encountered during transportation induced lymphopenia, neutrophilia, and eosinopenia, which can cause immunosuppression. In GI goats, the administration of AA prior to loading and transportation ameliorated the adverse effects of loading and transportation stress on neutrophil/lymphocyte ratio and eosinopenia of the goats.

Daily Rhythms of Blood Parameters in Broiler Chickens Reared under Tropical Climate Conditions

Several studies carried out on humans and other mammals show that the temporal organisation of haematological parameters in the blood exhibit daily rhythms; however, such studies have been rare in poultry reared under a natural photoperiod. The present study investigated the occurrence of daily rhythms in blood parameters of broiler chickens kept under tropical climatic conditions. Ten 6–7-week-old broiler chickens served as subjects of the study. They were kept in standard individual cages under natural light-dark cycle and given access to feed and water ad libitum. Two milliliters of blood was collected from each bird via intravenous cannulae inserted into the wing vein. The blood samples were collected every 4 h over a 24-h period, starting from 09:00 h on the first day and completed at 09:00 h on the second day. The blood samples were analysed for erythrocyte, total and differential leucocyte counts. A trigonometric statistical model according to the single cosinor procedure was used to describe the periodic parameters and their acrophases, and ANOVA was used to determine significant differences. The results demonstrated the existence of daily rhythms in packed cell volume, haemoglobin, white blood cell, red blood cell, heterophil, lymphocyte, eosinophil and monocyte counts, while total protein displayed no rhythm. The characteristics of the haematological parameters showed that the acrophases were restricted to the light phase of the light/dark cycle, precisely at 09:00 h, except for eosinophil and heterophil counts, which had acrophases at 21:00 h. The amplitudes of the blood parameters varied, with packed cell volume having the greatest amplitude of 4.2 ± 0.5, closely followed by lymphocyte (3.4 ± 0.5) and heterophil (2.3 ± 0.2) counts. In conclusion, the results of the study demonstrated the existence of daily rhythms with diurnal acrophases in blood parameters of broiler chickens kept under natural photoperiods and tropical conditions.

Diurnal rhythms of heart and respiratory rates in donkeys of different age groups during the cold‐dry and hot‐dry seasons in a tropical savannah

The aim of this study was to determine the effect of season on diurnal rhythms of heart (HR) and respiratory rates (RespR) in the adult, yearling, and foal donkeys during the cold‐dry and hot‐dry seasons under natural light/dark cycle. The resting HR and RespR were recorded bihourly for 24 consecutive hours from 06:00 to 06:00 h (GMT +1) in 30, clinically healthy donkeys (10 adults,10 yearlings, and 10 foals). Dry‐bulb temperature (DBT), relative humidity (RH), temperature‐humidity index (THI) and wet‐bulb globe temperature index (WBGT) inside the pen were recorded bihourly from 06:00 to 06:00 h. Values of DBT, THI, and WBGT obtained during the hot‐dry season were significantly (P < 0.05) higher than corresponding values recorded during the cold‐dry season. Application of single‐cosinor procedure showed that HR and RespR exhibited daily rhythmicity in both seasons. The mesors of the HR in adult (41.51 ± 0.34 beats/min [bpm]), yearling (40.80 ± 0.43 bpm), and foal (47.55 ± 0.40 bpm) donkeys during the cold‐dry season were significantly (P < 0.01) lower, compared to the corresponding values of 48.4 ± 0.40 bpm, 50.42 ± 0.52 bpm and 58.10 ± 0.50 bpm, respectively during the hot‐dry season. The mesors of RespR in adult, yearling, and foal donkeys during the hot‐dry season were higher (P < 0.05), when compared to the corresponding values recorded in the cold‐dry season. The HR and RespR of foals were significantly (P < 0.05) higher than those of the adult and yearling donkeys. Amplitudes of HR and RespR were higher during the hot‐dry season than the cold‐dry season. In conclusion, seasonal changes affect diurnal rhythmicity of HR and RespR of adult, yearling, and foal donkeys during the cold‐dry and hot‐dry seasons. The HR and RespR of donkeys vary with age, with higher values in the foals than the adult and yearling donkeys in both seasons.

Daily rhythmicity of behavioral responses in donkeys of different age groups during the cold-dry (harmattan) and hot-dry seasons in a tropical savannah

ABSTRACT The aim of the study was to evaluate the daily rhythms of behavioral activities of adult, yearling, and foal donkeys during the cold‐dry (harmattan) and hot‐dry seasons in a tropical savannah. Thirty, clinically healthy free‐ranging donkeys, divided into 3 groups of 10 donkeys each according to their age, served as experimental subjects. Behavioral activities of donkeys were monitored bihourly from 06:00 to 06:00 h (GMT +1) during the cold‐dry and hot‐dry seasons. Application of single cosinor procedure showed that behavioral activities exhibited varying levels of daily rhythmicity in both seasons. Behavioral activities of adult, yearling, and foal donkeys peaked during the afternoon period (13:11–14:45 h) of the photophase of the light–dark cycle during the cold‐dry and hot‐dry seasons. The diurnal index of activity rhythm showed that donkeys are mostly diurnal animals. During the study period, the percentage time spent on feeding during the harmattan season was higher (P < 0.05) than during the hot‐dry season in adults (37.38 ± 1.57% vs 30.72 ± 1.29%), yearlings (33.20 ± 1.43% vs 27.00 ± 1.25%), and foals (16.79 ± 0.82% vs 14.38 ± 0.65%). The percentage time spent dozing during the hot‐dry season by adults (28.21 ± 1.59%), yearlings (29.31 ± 1.60%), and foals (37.64 ± 1.48%) was higher (P < 0.05), when compared with the corresponding values (23.75 ± 1.55%, 26.43 ± 1.59% and 42.42 ± 1.40%, respectively) obtained during the harmattan season. In conclusion, daily rhythmicity of behavioral activities in donkeys, kept under natural light–dark cycle, was similar in both seasons, although the intensity of activity was higher in the cold‐dry than the hot‐dry season. This finding may be useful in the management, improvement of productivity, and welfare of working donkeys under different thermal environmental conditions.

Circadian rhythms of biomarkers of oxidative stress and their characteristics in broiler chickens reared under natural light/dark cycle

Abstract For the purpose of studying circadian rhythms of biomarkers of oxidative stress in broiler chickens maintained under natural photoperiod, we collected blood from the wing veins of 10 matured broiler chickens every three hours for a period of 24 h. The blood samples were analyzed for superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA). The fitting in of single cosinor procedure showed that CAT and MDA exhibited clear circadian rhythms, while SOD did not. The amplitude of daily rhythms for the parameters was small, while the acrophases were all restricted to the light phase of the light:dark cycle. In conclusion, to our knowledge, this is the first time investigation of the circadian rhythms of antioxidants in broilers chickens, reared under natural photoperiod in the tropics. The result may be exploited for a more precise targeting of reactive oxygen species, thereby offering better protection for the cells to combat oxidative stress.