Dairy science and health in the tropics: challenges and opportunities for the next decades

EditorialIn the next two decades, the world population will increase significantly; the majority in the developing countries located in the tropics of Africa, Asia, Latin America, and the Caribbean. To feed such a population, it is necessary to increase the availability of food, particularly high-value animal protein foods produced locally, namely meat and dairy products. Dairy production in tropical regions has a lot of growth potential, but also poses a series of problems, particularly as dairy production systems were developed in temperate countries and in most cases are difficult to implement in the tropics. Drawbacks include hot weather and heat stress, the lack of availability of adequate feeds, poor infrastructure, and cold chain and the competition with cheap imports from temperate countries. This position paper reviews the major drawbacks in dairy production for the five major dairy species: cattle, water buffalo, sheep, goat, and camel, as well as the future trends in research and development. It also concerns the major trends in reproduction and production systems and health issues as well as environmental concerns, particularly those related to greenhouse gas emissions. Tropical Animal Health and Production now launches a topical collection on Tropical Dairy Science. We aim to publish interesting and significant papers in tropical dairy science. On behalf of the editorial board of the Tropical Animal Health and Production, we would like to invite all authors working in this field to submit their works on this topic to this topical collection in our journalinfo:eu-repo/semantics/publishedVersio

Short communication: Supply of methionine during late pregnancy enhances whole-blood innate immune response of Holstein calves partly through changes in mRNA abundance in polymorphonuclear leukocytes

The supply of methionine (Met) in late pregnancy can alter mRNA abundance of genes associated with metabolism and immune response in liver and polymorphonuclear leukocytes (PMN) of the neonatal calf. Whether prenatal supply of Met elicits postnatal effects on systemic inflammation and innate immune response of the calf is not well known. We investigated whether enhancing the maternal supply of Met via feeding ethyl-cellulose rumen-protected Met (RPM) was associated with differences in calf innate immune response mRNA abundance in PMN and systemic indicators of inflammation during the first 50 d of life. Calves (n = 14 per maternal diet) born to cows fed RPM at 0.09% of diet dry matter per day (MET) for the last 28 ± 2 d before calving or fed a control diet with no added Met (CON) were used. Blood for biomarker analysis and isolation of PMN for innate immune function assays and mRNA abundance was harvested at birth (before colostrum feeding) and at 7, 21 and 50 d of age. Whole blood was challenged with enteropathogenic bacteria (Escherichia coli 0118:H8) and phagocytosis and oxidative burst of neutrophils and monocytes were quantified via flow cytometry. Although concentration of haptoglobin and activity of myeloperoxidase among calves from both maternal groups increased markedly between 0 and 7 d of age followed by a decrease to baseline at d 21 the responses were lower in MET compared with CON calves. Nitric oxide concentration decreased markedly between 0 and 7 d regardless of maternal group but MET calves tended to have lower overall concentrations during the study. In vitro phagocytosis in stimulated neutrophils increased markedly over time in both CON and MET calves but responses were overall greater in MET calves. Oxidative burst in both neutrophils and monocytes increased over time regardless of maternal treatment. The mRNA abundance of lactate dehydrogenase (LDHA) signal transducer and activator of transcription 3 (STAT3) and S100 calcium binding protein A8 (S100A8) in PMN was overall greater in MET calves. Overall data suggest that increasing the maternal supply of Met during late pregnancy could affect the neonatal calf inflammatory status and innate immune response. Although changes in mRNA abundance could play a role in coordinating the immune response the exact mechanisms merit further study

Effect of inclusion of zinc-glycine chelate and zinc sulphate on live performance, immunity and lipid peroxidation in broilers

ABSTRACTZinc (Zn) is a biologically significant trace mineral, serving as a cofactor in various metabolic functions. This study aimed to assess the relative effectiveness of organic and inorganic Zn on the growth performance, lipid peroxidation and humoral immune response in broiler chickens (Ross 308). A total of 450 d-old broilers were divided into five groups: the control group, a group receiving a basal diet with 50 mg/kg organic Zn (T1), another with 60 mg/kg organic Zn (T2), and two groups with basal diets supplemented with inorganic Zn at rates of 50 and 60 mg/kg zinc sulfate for the fourth (T3) and fifth (T4) groups, respectively. The experiment spanned 35 days. Results indicated that zootechnical characteristics such as weekly weight gain, feed intake, feed conversion ratio and dressing percentage were significantly higher (P < 0.05) in T1 compared to both the control and the inorganic Zn supplementation groups. Additionally, the antibody titre against Newcastle disease was significantly (P < 0.05) elevated, while malondialdehyde (MDA) levels were significantly (P < 0.05) lower in T1 and T2 compared to the control and the inorganic Zn supplementation groups. In conclusion, broilers supplemented with 50 mg/kg organic Zn exhibited significantly improved growth performance, reduced MDA levels, and enhanced humoral immune response

Effects of Different Levels of Yucca Supplementation on Growth Rates, Metabolic Profiles, Fecal Odor Emissions, and Carcass Traits of Growing Lambs

Sixty male Awassi lambs were used to investigate the effects of dietary Yucca schidgera extract (YS) on the production, fecal and urinary odor emissions, and carcass traits of growing lambs fed complete pellets. Lambs were fed either a complete pelleted diet without yucca (control) or supplemented with 300 or 600 mg YS/kg dry matter (DM) during the 84-day experiment. The weights and feed consumption of the lambs were measured weekly. Blood samples were taken on days 1, 28, 58, and 84, and ruminal fluid samples were collected on day 70. On day 90, the odor emissions from feces and urine were measured. On day 84, 12 lambs were slaughtered for the evaluation of carcass and meat quality. The final values for bodyweight, bodyweight gain, and feed efficiency of lambs fed the YS300 diet were 3.40%, 6.64%, and 6.17%, respectively, higher (p 600 diet. Additionally, the percentage of dressing, myofibril fragmentation index, and ruminal isovalerate percentage of lambs treated with YS600 were higher than those treated with YS300. Compared with the control, the addition of yucca reduced odor emissions from feces and urine. In conclusion, dietary YS300 had no additional benefits on growth rate, feed efficiency, and carcass traits, while dietary YS600 improved fecal and urinary odors

Bacterial or fungal origin phytase enzyme affects the performance and mineralization of calcium and phosphorus differently in broiler chickens fed deficient calcium and phosphorous diets

ABSTRACTThree Ca-P deficient diets viz., Diet-1 (0.85%, 0.35%), Diet-2 (0.75%, 0.30%) and Diet-3 (0.65%, 0.25%) were prepared and supplemented with either bacterial or fungal origin phytase enzymes and were compared with a control diet (1.0% and 0.45%). A total of 280 broiler (Ross 308) chicks were randomly allocated into 7 treatments having 4 replicates of 10 chicks using a completely randomized design. The effect of bacterial phytase on the growth, FCR and carcass weight was significantly (P < 0.05) higher in chicks on Diet-1 compared to diet-3 (28 days). Bacterial phytase increased serum minerals (Ca and P) and tibia ash in diet-1 compared to Diet-3. Tibia Ca was significantly (P < 0.05) higher in the control and the three diets under bacterial phytase compared to other treatments. On Diet-3, more Ca and P were reflected in tibial by bacterial phytase but did not support the optimum growth performance of broiler chicks. In conclusion, the same phytase but of different origins might have specific individual effects on the growth performance, serum and tibia Ca and P in broilers

Antioxidant status and immune responses of growing camels supplemented a long-acting multi-trace minerals rumen bolus

The study was conducted to evaluate the effects of a long-acting trance mineral rumen bolus supplementation on enzymatic and haematological profiles, antioxidant status and immune responses of growing camels under natural grazing conditions. Fifteen 6-month-old growing male camels were used in a 150-day trial. Animals were individually housed in a shaded pen and randomly assigned to receive 0 (CON), one (TMB1) or two (TMB2) long-acting trance mineral rumen bolus. Blood samples were collected from all camels on days 1, 30, 60, 90, 120 and 150 to measure enzymatic concentrations in serum, total antioxidant capacity (TAC) in plasma and haematological variables in whole blood. Camels were injected intradermally with 0.25 mg phytohaemagglutinin (PHA) on days 90 and 140, and then the cell-mediated immune response to this antigen was measured at 0 and 24 h after injection. Animals were immunised intravenously on days 90 and 105 with 2 ml suspension of sheep red blood cells to measure total antibody titres in serum. Using TMB supplement (1 or 2 boluses) resulted in an increase in the plasma concentration of TAC (p < 0.04) and improvement in immune responses in terms of increased skinfold thickness after 24 h of PHA injection (p < 0.01) and total primary serum antibody titres (p < 0.04). Different levels, sources, and synergistic combinations of trace minerals can be used in further studies to elucidate the most advantageous regarding productive variables, availability and cost for camel industry

Effects of Feeding Different Levels of Sprouted Barley on Fermentation Characteristics, Bacterial Quantification, and Rumen Morphology of Growing Lambs

The objective of the present study was to investigate the effects of sprouted barley inclusion level on the growth performance, digestibility, volatile fatty acids, bacterial quantification, and rumen morphology of growing lambs. Five dietary treatments with sprouted barley (0, 25, 50, 75 and 100%) and nine replicates per dietary treatment were performed on forty-five Awassi lambs (90 days old). The average weight gain, intake, and digestibility of dry and organic matter were recorded. The pH, color, volatile fatty acids, bacterial quantification, and rumen histomorphometry were also determined. The results showed that the average dry and organic matter intake in T2 to T4 and the average weight gain in T4 decreased linearly. In contrast, the digestibility of dry and organic matter by sprouted barley (T2 to T4) was higher. The pH values and rumen color were not affected. Concentrations of formic acid, acetic acid, butyric acid, and the ratio of acetic acid to propionic acid were increased, while lactic acid and total volatile fatty acids were lower in all levels of sprouted barley. In addition, lambs fed T4 had a higher quantification of Anaerovibrio Lipolytica, Butyrivibrio Fibrisolvens, and Streptococcus Bovis quantification. Selenomonas Ruminantium was higher in T1, T2, and T4, whereas Megashpaera Elsdenii was lower in T1 to T3. The rumen histomorphometric was improved by sprouted barley (T2 and T3). Sprouted barley improved digestibility and rumen histomorphometry and increased the concentration of some volatile fatty acids and rumen bacteria but resulted in a decrease in average dry and organic matter intake, which negatively affected weight gain in lambs fed 100 % sprouted barley. Further studies are required to determine the potential effects on growing lambs fed sprouted barley

Haematological alterations under the anti-helminthic application in Pavo cristatus

ABSTRACTAnti-helminthic drugs (Albendazole and Levamisole) trials were conducted on Indian Peafowls (n = 20) kept at Jallo Wildlife Park, Lahore, Pakistan for 15. Sampling was conducted on days 7 and 15 of treatments. The results showed that the WBC count was significantly (P < 0.05) higher in both samples in response to Levamisole treatment. Haemoglobin (HGB) and Mean Corpuscular Haemoglobin Concentration (MCHC) concentration increased significantly (P < 0.05) in response to both treatments; however, Mean Corpuscular Haemoglobin (MCH) decreased significantly (P < 0.05) in Albendazole-treated birds on both the sampling days compared to the control. Red Blood Cell Distribution Width-Standard Deviation (RDW-SD) decreased significantly (P < 0.05) in all treatment groups. On the other hand, the prevalence of eggs per gram (EPG) was reduced by 20% after the application of Levamisole on days 7 and 15. It was concluded that both drugs had significant effects on WBCs, HGB, MCH, MCHC and RDW-SD

Effects of dietary inclusion of Moringa oleifera methanolic extract on productive performance, humoral immunity and nutrient digestibility in Japanese quails

ABSTRACTA total of 180 unsexed, 1-day-old quail chicks were divided into four treatments (three replicates). The treatment groups were designated as MOLE-0, MOLE-1, MOLE-2 and MOLE-3. In the MOLE-0 group, quails received a basal diet without supplementation. For MOLE-1, quails were provided with 100 mg/L of MOLE in their water, while MOLE-2 received 200 mg/L of water with MOLE supplementation. The fourth treatment, MOLE-3, received a concentration of 300 mg/L of MOLE in their drinking water. The findings revealed that MOLE-3 exhibited significantly higher weight gain and dressing percentage, along with a lower feed conversion ratio (P < 0.05), while the control group (MOLE-0) exhibited the least growth performance. MOLE-3 showed statistically higher antibody titres and immune organ weights, followed by MOLE-2 and MOLE-1. Conversely, the control group (MOLE-0) had a lower antibody titre against ND. Additionally, nutrient digestibility analysis indicated that MOLE-3 had higher digestibility of dry matter and crude protein (P < 0.05), while group MOLE-0 exhibited lower digestibility (P < 0.05). We concluded that supplementing Moringa oleifera leaf extract at a rate of 300 mg/L resulted in improved growth performance, immunity and nutrient digestibility in Japanese quails