Volatile fatty acids production in ruminants and the role of monocarboxylate transporters: A review

Monocarboxylates commonly referred to as short-chain fatty acids (SCFAs) are metabolized to different extents by the epithelium of the gastrointestinal tract. They are absorbed along different segments of the gastrointestinal tract and constitute a significant amount of energy in ruminants. Monocarboxylates play a central role in cellular metabolism and metabolic communication between tissues. Essential to these roles is their rapid transport across the plasma membrane, which is catalyzed by a recently identified family of proton-linked monocarboxylate transporters (MCTs). Monocarboxylate transporter-1 and 4 have been shown to interact specifically with OX-47 (CD147), a member of the immunoglobulin superfamily with a single transmembrane helix. This interaction appears to assist MCT expression at the cell surface. Despite the importance of short-chain fatty acids in being the main energy source in ruminant animals, the mechanism of SCFAs transport and absorption is still not fully studied. The aim of this review is to critically discuss short-chain fatty acids production and the functional role of monocarboxylate transporters in relation to the transport and absorption of these nutrients along the gastrointestinal tract of ruminants. Two major functions of monocarboxylate transporter proteins, namely the facilitation of the absorption of SCFAs in the gastrointestinal tract and the regulation of cell pH in skeletal muscles, are clearly very important for physiological homeostasis, animal welfare and productivity.Key words: Ruminants, monocarboxylates, monocarboxylate transporters, CD147

Livestock-environment interactions: Methane emissions from ruminants

Livestock producers face a number of challenges including pressure from the public to be good environmental stewards and adopt welfare-friendly practices. However, environmental stewardship and animal welfare may have excitingly conflicting objectives. Examples include pasture-based dairy and beef cattle production where high-fiber diets increase methane emissions compared with grain feeding practices in confinement. Livestock account for 35-40% of global anthropogenic emissions of methane, via enteric fermentation and manure, which together account for about 80% of the agricultural emissions. Recent estimates indicate that the methane emissions from African cattle, goats, and sheep are likely to increase from their current level of about 7.8 million tons of methane per year in 2000 to 11.1 million tons per year by 2003, largely driven by increase in livestock numbers. This paper therefore reviews certain areas of CH4 emissions from ruminants, highlights on how some novel feed additives can decrease CH4 emissions from ruminants; and how some plants secondary metabolites might act as a selective inhibitor of methanogens. An enteric methane emission (which is one of the greenhouse gases) represents an economic loss to the farmer where feed is converted to CH4 rather than to product output. As developing countries are now responsible for almost three-quarters of such emissions, this has important implications in terms of mitigation strategies, because these countries are presently outside the remit of the Kyoto Protocol.Key words: Environment, CH4 emissions, feed additives, mitigation, ruminants

Pycnogenol improves kinematic parameters of donkeys (Equus asinus) subjected to packing during the dry season

The administration of pycnogenol (PYC) prior to physical exertion had earlier shown to improve gait variables after work. The aim of this study was to determine the effect of PYC on kinematic parameters of donkeys subjected to packing during the dry season. Ten male donkeys served as experimental subjects. Five donkeys were administered with PYC (10 mg/kg) in feed (test group) while another five donkeys were given feed only (control group) for one week pre-packing. Thermal environmental parameters of ambient temperature (AT), relative humidity (RH) and temperature humidity index (THI) were recorded. Kinematic parameters of speed (SP), stride length (SL), stride frequency (SF) and stride duration (SD) using videographic recordings 5 minutes post-packing with each animal walking at a self-selected speed were recorded. The THI values obtained pre- (95.4 ± 3.9) and during (85.3 ± 1.6) packing in the cold-dry season were significantly lower than the values of 148.8 ± 1.8 and 134.8 ± 1.1, respectively obtained during the hot-dry season. The speed recorded in test group (2.0 ± 0.3 m/s) was significantly (P < 0.05) higher when compared to the value (1.3 ± 0.2 m/s) obtained in control group during the hot-dry season while, during the cold-dry season, the test group recorded a significantly (P < 0.05) higher speed (1.3 ± 0.3 m/s) when compared with 1.0 ± 0.2 m/s recorded in control group.The increased speed recorded in the test group indicated that the group performed better as they were less fatigued when compared with the control group. Thus, PYC could be used as a potential agent in the management of fatigue in donkeys used for packing purposes in the region

Melatonin and garlic cytoprotective-ameliorative effects on dibutyl phthalate intoxication on sperm DNA and testicular biomakers of rabbits

The study investigated the cytoprotective and ameliorative effects of melatonin and Allium sativum (garlic) on dibutyl phthalate (DBP)-induced oxidative stress, its impact on sperm DNA integrity and testicular oxidative stress biomarkers. Forty two rabbit bucks were randomly divided into 7 groups of 6 bucks each labeled as A, B, C, D, E, F and G: The treatment were as follows: A (served as negative control, received olive oil for 16 weeks); B (served as positive control, exposed to DBP for 16 weeks, no treatment); C (given melatonin for 8 weeks, thereafter DBP for 8 weeks); D (administered garlic for 8 weeks, thereafter DBP for 8 weeks); E (exposed to DBP for 8 weeks, thereafter melatonin for 8 week); F (exposed to DBP for 8 weeks, thereafter garlic for 8 weeks); and G (exposed to DBP for 8 weeks, thereafter melatonin + garlic for 8 weeks). Ejaculated semen was collected on the last day (112th) using artificialv vagina for rabbit and pooled for each group was used for sperm DNA fragmentation index (SDFI) determination, rabbits were sacrificed and the testes harvested for determination of superoxide dismutase activity, reduced glutathione and malondialdehyde concentration. Results showed a significant increase (P = 0.0018) in the mean SDFI in group B (78.20 ± 4.72), compared to other groups. A significant increase (P ≤ 0.0001) in superoxide dismutase activity, increase reduced glutathione concentration and decrease malondialdehyde concentrations in the treatment groups compared to the DBP exposed group without treatment (group B) were observed. Melatonin and garlic demonstrated cytoprotective and ameliorative effects against DBP-induced oxidative stress in rabbit bucks. Keywords: Dibutyl phthalate, Garlic, Melatonin, Sperm DNA, Testicular biomarker

Melatonin and Allium Sativum (Garlic) Protect Dibutyl Phthalate Influence on Spermiogram of Rabbit Bucks

This study was designed to evaluate the effects of melatonin and Allium sativum (garlic) on  dibutyl phthalate (DBP) influence on  spermiogram of rabbit bucks. Forty two (42) rabbit bucks were used for this study, bucks were randomly divided into 7 groups of 6 bucks each. Group A was administered olive oil for 16 weeks, group B (olive oil + DBP for 16 weeks), group C (melatonin for 8 weeks, then olive oil + DBP for another 8 weeks), group D (garlic for 8 weeks, then olive oil + DBP for another 8 weeks), group E (olive oil + DBP for 8 weeks, then melatonin for another 8 week), group F (olive oil + DBP for 8 weeks, then garlic for another 8 weeks) and group G (olive oil + DBP for 8 weeks, then melatonin and garlic for another 8 weeks). The observation period lasted for 120 days, during which semen samples were collected weekly between the hours of 8.00 am to 10.00 am using artificial vagina (AV).There were significant differences (P<0.05) in mean reaction time, semen volume, sperm motility, sperm concentration, percentage live spermatozoa and percentage abnormal morphology between DBP exposed groups and treatment groups. Conclusion, DBP has adverse effects on spermiogram but administration of melatonin and garlic has promising protective effects than therapeutic effect on rabbit bucks. Key words: Melatonin; Allium sativum; Dibutyl phthalate; Spermiogram; Rabbit Buck

Influences of breed, sex and age on seasonal changes in haematological variables of tropical goat kids

The influences of breed, sex and age on seasonal changes in haematological variables of kids (1–4 months old) belonging to Red Sokoto (n  =  60) and Sahel (n  =  60) goats were studied at the peaks of the cold-dry, hot-dry and rainy seasons in a West Africa Guinea savanna climate. The results showed that, during the hot-dry season, Sahel goat kids had significantly higher (P  <  0.05) packed cell volume (PCV) and red blood cell (RBC) count but lower (P  <  0.05) mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC) and total leucocyte count than Red Sokoto kids. Similarly, younger kids of both breed had significantly higher (P  <  0.05) PCV and RBC but lower MCV, MCH and MCHC compared with the older kids during the hot-dry season. Younger kids (1–2 months) of both breeds exhibited significantly (P  <  0.05) high PCV and RBC but low MCH and MCHC during the hot-dry season as compared with the cold-dry and rainy seasons, with the magnitude of the change being greater in Sahel kids. More remarkable seasonal fluctuations in haematological parameters were observed in buck kids than doe kids of both breeds. Multivariate analysis revealed a clear distinction between the change in haematological parameters during the cold-dry as compared with the hot-dry and rainy seasons, with MCV having the strongest discriminating power (0.91*). In conclusion, breed, age and sex variations in haematological variables of goats were more pronounced in the hot-dry season, during which the seasonal changes were more dramatic in kids of Sahel goats, as well as in younger and male kids of both breeds. These findings may be useful in the management of tropical goat kids in different seasons

Growth Performance of Broilers fed Moringa oleifera Supplemented Feed and Challenged with a very virulent Infectious Bursal Disease Virus

A study was conducted to assess the growth performance of broiler chickens fed Moringa oleifera leaf (MOL) feed supplementand challenged with a very virulent infectious bursal disease virus (vvIBDV). Two hundred and forty day-old Ross 308 hybridbroiler chicks were randomly assigned into groups A, B, C and D of 60 chicks each and were raised in deep litter housing.Broiler starter (BS) and broiler finisher (BF) mash were formulated each with 5% MOL included as part of the feed ingredientfor broilers in groups A and B while BS and BF for broilers in groups C and D were formulated without MOL. Broiler chickensin groups A, B and C were challenged at 35 days of age with 0.05 ml of a live vvIBDV, while those in group D served ascontrol. Daily feed intake (DFI), feed conversion ratio (FCR) and average body weight gain (ABWG) was used to assess thegrowth performance. At 42 and 49 days of age, significant difference was observed in the feed intake of broilers in groups A,B and C when compared with group D (p = 0.0001). At 49 days of age, broilers in group A and D significantly (p = 0.0001)added more weight than those in groups B and C respectively. Broilers in group B had a significantly (p = 0.0006) lower FCRthan those in group A, C and D at 28, 35 and 42 days of age. Despite the challenge with vvIBDV, MOL inclusion in the diet ofbroiler chickens resulted in reduced DFI, good FCR, increased ABWG and final body weight and carcass weight. Keywords: Average Body Weight Gain; Broilers; Feed Conversion Ratio; Moringa oleifera lea

Pseudo-Mobitz Type II atrioventricular block in a Nigerian indigenous dog

No AbstractKeywords: heart block, antioxidants, Nigerian indigenous do