Relationship between saliva and blood cortisol in handled cows.

OBJECTIVE: The objective of the study was to determine the relationship between plasma and salivary cortisol concentrations in beef cattle that were subjected to handling prior to sampling. METHODS: Twenty-one Nguni cows of three age categories; 5 to 7 yr (n = 7), 8 to 10 yr (n = 6), and 11 to 13 yr (n = 8) were handled for five consecutive weeks. In the pen, a human avoidance test was performed and cattle responses to restraint in the chute and crush were observed. In addition, rectal temperature readings were taken and, faecal samples were collected and analysed for glucocorticoid metabolites. Through the handling and restraint process, excretory and vocalisation behaviour, as a sign of stress were observed and recorded. Thereafter, six cows were randomly selected and subjected to an adrenocorticotropic hormone (ACTH) challenge. Blood and saliva samples were extracted to determine cortisol concentrations. RESULTS: Repeated handling affected (p<0.05) faecal glucocorticoid metabolites, rectal temperatures, avoidance distance, crush scores as well as urination and defaecation behaviour. Acclimation to handling was variable based on each respective parameter. Saliva cortisol concentrations increased and decreased significantly (p<0.001). A peak value of 136.78± 15.869 nmol/L was observed 30min after administration of ACTH, from a baseline value of 8.75± 15.869 nmol/L. Plasma cortisol concentrations did not differ (p>0.05) across the time of sampling. A low and insignificant correlation (r = 0.0131, p>0.05) between plasma and saliva cortisol was therefore observed. CONCLUSION: We conclude that if beef cows are subjected to handling prior to sampling, a weak relationship exists between plasma and salivary cortisol levels.

Changes in biochemical proxy indicators for nutritional stress resilience from Boran and Nguni cows reared in dry arid rangeland.

The objective of this study was to determine the changes in biochemical indicators for nutritional stress from a herd of Boran and Nguni cows. A total of 40 cows (20 from each herd) were randomly selected for the study. The animals were identified according to their parities as follows: parity 1 (n = 8), parity 2 (n = 16), parity 3 (n = 8) and parity 4 (n = 8). Serum chemistry levels of glucose, total cholesterol, urea, creatinine, albumin, globulin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutylaminotransferase (GGT), leukocytes, erythrocytes, haemoglobin, packed cell volume (PCV) and platelet counts were determined for 12 consecutive months spanning across the wet and dry seasons. The Boran cows had different creatinine concentration levels at different parities. The Boran cows in parity 1 had the highest (P < 0.05) concentration of creatinine 87.2 ± 5.17 µmol/L than other cows in different parities within the herd. There were significant differences in enzymes such as AST, ALP and ALT among the herd and parities. Boran cows in parity 3 had the lowest (P < 0.05) AST concentration levels of 52.6 ± 3.48 U/L, Nguni cows in parity 4 had the highest concentration of ALP of 161.3 ± 8.10 U/L while Nguni cows in parity 1 had the highest concentration level of ALT 55.1 ± 1.56 U/L than all the cows within the same herd. The Nguni herd had significantly higher (P < 0.05) levels of creatinine in both the wet (97.8 ± 3.27 µmol/L) and dry seasons (108.7 ± 3.29 µmol/L) compared with the Boran herd. Cows from the Nguni herd maintained significantly higher amount of urea, creatinine, albumin and total protein in both the wet and dry seasons as compared with cows from the Boran herd. Cows from the Nguni herd maintained significantly higher amount of urea, creatinine, albumin and total protein in both the wet and dry seasons as compared with those from the Boran herd.

Farmers' perceptions of goat kid mortality under communal farming in Eastern Cape, South Africa.

Rearing of goats under communal farming conditions is characterised by high kid mortality and low weaning percentages. A survey was conducted to determine farmers' perceptions on the causes of kid mortality during summer under the communal farming system in Nkonkobe Local Municipality in the Eastern Cape, South Africa. This was done by administering questionnaires to a total of 162 respondents in 14 villages around Nkonkobe Local Municipality. The study showed that majority of farmers (75 %) keep flock sizes of less than 10 goats and kids, and this indicates that goat production in Nkonkobe Local Municipality is suppressed. According to the farmers, diseases (89 %), endo-parasites (72 %) and ecto-parasites (68 %) were perceived as the major causes of kid mortality. Other causes reported include starvation (15 %), extreme weather conditions (28 %), abortion (7 %), theft (35 %), diarrhoea (43 %), accidents (10 %) and wounds (9 %). The low number of goats could be attributed to high mortalities. It was also found that all causes reported by farmers played a role in high kid mortality in Nkonkobe Local Municipality. However, the causes which require more emphasis to formulate extension support were tick-borne diseases and parasites. This study provided baseline information on possible causes of kid mortalities in Nkonkobe Local Municipality. There is, however, a need to conduct further studies to determine actual causes of high kid mortalities so as to develop preventive strategies that would minimize kid mortality for good economic returns.