Effect of access to outdoor grazing and stocking density on space and pasture use,behaviour, reactivity,and growth traits of weaned rabbits

In a context of evolving concern over housing conditions of farmed rabbits, we developed a housing system that allows access to an outdoor area. The aim was to study the health status, growth and behaviour of rabbits raised at two stocking densities with access to a paddock, or not. We distributed 299 weaned rabbits in four groups (YH: 100, NH: 99, YL: 50 and NL: 50) using a 2 × 2 factorial design including access (Y: yes) or not (N: not) to a 23 m² paddock and the indoor stocking density (H, high: 17 or L, low: 9 rabbits/m²). We measured the growth and health status of each animal weekly for 42 days (from 31 to 73 days of age) and performed reactivity tests to a new environment, a human and new object. We also assessed the rabbits’ behaviour at days 26 and 40 by doing a visual scan of each animal at regular time intervals. Our results showed that stocking density had no effect on mortality, but mortality tended to increase with outdoor access from 3.0% to 7.0% (P < 0.10). Although the stocking density had no effect on average daily gain, it was higher in rabbits in the N group than in the Y group (+3.6 g/day; P < 0.05). Rabbits entered the paddocks for the first time in less time at the beginning of the trial (50 s at day 3 vs 10 min at day 31; P < 0.001). The proportion of rabbits outside after 20 min of the new environment test was higher among rabbits in the L group than in the H group (+24% points at day 3 and +11% points at day 20; P < 0.001). Regardless of the stocking density, more rabbits in the N group touched the experimenter’s hand (16% vs 27%; P < 0.05) and the new object (34% vs 20%; P < 0.05) than rabbits in the Y group. Inactivity was more frequent in rabbits inside the pens than in the paddocks (70.0% vs 34.2% at days 26 and 40; P < 0.05). Locomotion was more frequent in the paddocks than in the indoor pens (20.0% vs 7.2% at days 26 and 40; P < 0.05). The stocking density did not affect the behavioural traits measured. In conclusion, providing rabbits access to a paddock could allow them to fulfil some natural behaviours but slightly reduced their growth.     

Effects of time-based feed restriction on morbidity,mortality, performance and meat quality of growing rabbits housed in collective systems

In rabbit farms, quantitative feed restriction in the post-weaning period is widely used with the aim of reducing the impact of digestive diseases, whereas less information is available about feed restriction strategies based on the reduction of access time to feeders in different housing systems. This study compared morbidity, mortality, growth performance, carcass characteristics and meat quality of 368 crossbred rabbits fed ad libitum (L) or subjected to a time-based feed restriction programme (R) and housed from 31 to 73 days of age in cages or pens with different dimensions and group sizes, that is, eight conventional cages (0.33 m², six rabbits/cage), eight small open-top pens (0.50 m², eight rabbits/pen), eight medium open-top pens (1.00 m², 16 rabbits/pen) and four large open-top pens (2.00 m², 32 rabbits/pen). Feed restriction was attained by progressively reducing the access time to feeders in the 1st week from 14 to 8 h/day, maintaining 8 h in the 2nd week and then by increasing access time by 1 h/day during the 3rd and 4th week up to 24 h/day. In the first 2 weeks, R rabbits showed a lower (P ≤ 0.001) daily weight gain, feed intake and feed conversion as compared with L rabbits. During the 3rd and 4th weeks, R rabbits exhibited a greater daily weight gain and better feed conversion (P ≤ 0.001). In the last 2 weeks of trial, daily weight gain tended (P = 0.06) to be greater in the R than L rabbits. In the whole trial, R rabbits manifested a lower daily weight gain, feed intake and feed conversion, as well as lower final live weight and the carcass dressing percentage at slaughter (0.05 ≤ P ≤ 0.01). During feed restriction, R rabbits did not show digestive problems, which, however, appeared in the following 2 weeks of refeeding. Thus, R rabbits had a higher health risk index in the whole trial as compared with L rabbits (P ≤ 0.05). The housing system did not affect growth performance, characteristics at slaughter, and carcass and meat quality. Mortality tended to increase with group size (P = 0.06). In conclusion, the time-based feed restriction significantly improved feed efficiency of growing rabbits housed collectively but had somewhat negative effects on characteristics at slaughter and on morbidity and mortality rate.     

Restricting dairy cow access time to pasture in autumn: The effects on milk production,grazing behaviour and DM intake of late lactation dairy cows

Extending the grazing season in pasture based systems of dairy production can increase farm profitability; poor weather and soil conditions can reduce the number of grazing days. The study objectives were to (i) examine the effect of restricted access to pasture in the autumn on the milk production, grazing behaviour and DM intake (DMI) of late lactation spring-calving dairy cows and (ii) establish the effect of alternating restricted and continuous access to pasture on dairy cow production, DMI and grazing behaviour. Cows were randomly assigned to one of four grazing treatments: (i) 22 h (full-time) access to pasture (22H; control); (ii) Two 5-h periods of access to pasture (2×5H); (iii) Two 3-h periods of access to pasture (2×3H); and (iv) alternating between full-time and 3-h access to pasture with no more than three continuous days on any one regime, e.g. Monday – full-time access, Tuesday − 2x3H access, Wednesday − 2x3H access; Thursday – full-time access, etc. (2×3HV). Restricted access to pasture was offered after a.m. and p.m. milking. Swards of similar quality and pregrazing herbage mass were offered. Treatment had no effect on milk yield (13.2 kg/day), milk fat (48.2 g/kg), protein (39.0 g/kg) or lactose content (42.6 g/kg) and milk solid yield (1.15 kg/day). Similarly, there was no effect of treatment on final BW (483 kg) or final BCS (2.66). There was no significant difference in DMI (15.1 kg DM/cow/day) between treatments. There was an effect on daily grazing time, 22H cows (565 min/cow/day) grazed for longest time, however, when the 2x3HV treatment had full-time access to pasture, they had a similar grazing time (543 min/cow/day) to the 22H cows and were similar to the 2x3H treatment on days with restricted access to pasture (357 min/cow/day). The 22H and 2x5H animals had similar grass DMI/min (29.2 g/min), the 2x3HV were higher (33.9 g/min) but were similar to the comparable treatment when offered 2x3H access time (41.6 g/min) and when offered 22H access time (27.7 g/min). The results from this study show how when offered a grass only diet of autumn pasture grazing behaviour can be modified by restricting pasture access time without reducing dairy cow production in late lactation at low production levels. There was also no effect of alternating access time between 22H and 2x3H on milk production and DMI in the 2x3HV treatment. Restricted access time to pasture in autumn may be a strategy which farmers can use to extend the grazing season.     

Effect of ambient temperature on the productive and carcass traits of growing rabbits divergently selected for body fat content

Rabbits are particularly sensitive to heat stress which can affect productive performance, with rabbit breed/line possibly playing a role on the response to this condition. The study aimed at evaluating the effect of different ambient temperatures on the live performance and carcass traits of growing rabbits divergently selected for total body fat content. The two genetic lines (Lean and Fat) were selected based on the total body fat content estimated by computer tomography during five generations. From birth to slaughter (13 weeks of age), the rabbits were housed in two rooms where the temperature was controlled with air conditioners: in the control room the average ambient temperature was 20 °C and in the high temperature room it was 28 °C. After weaning (35 d), 60 Lean and 60 Fat rabbits/room were housed by two in wire-mesh cages and fed ad libitum with commercial pellets. The BW and feed intake (FI) were measured at 5, 7, 9, 11 and 13 weeks of age to calculate the daily weight gain (DWG) and feed conversion ratio (FCR). Mortality was recorded daily. At the end of the experiment, rabbits were slaughtered and carcass traits were measured. Mortality was independent of temperature and line. The temperature significantly influenced the FI, DWG, BW and the fat deposits: they were lower at higher ambient temperature. The effect of temperature differed according to the rabbits' total body fat content. At control temperature, the FI (165 vs 155 g/day; P < 0.05) and FCR (4.67 vs 4.31; P < 0.05) were higher in Fat rabbits, which also had more perirenal (36.2 vs 23.1 g; P < 0.05) and scapular fat (10.8 vs 7.1 g; P < 0.05). At high temperature, no differences in fat depots (14.5 vs 9.8 g; 5.3 vs 3.5 g) were found between the two lines. It can be concluded that temperature × genetic line interaction had an important role in productive and carcass traits, as the effect of temperature differs between Lean and Fat rabbits.     

Impact of feed restriction and fragmented feed distribution on performance,intake behaviour and digestion of the growing rabbit

Postweaning feed restriction preserves rabbit digestive health after weaning, but the underlying physiological mechanisms are not yet understood. To elucidate whether the feeding intake pattern modification related to feed restriction might be involved, we studied the effects of both feed intake quantity and intake frequency. Animals were allotted at weaning (28 d old) in a 2 × 2 factorial design: feed intake quantity (AL = ad libitum vs R = 75% of AL) and fragmented feed distribution (FFD) (1 vs 13 distributions), thus forming four groups (AL1, AL13, R1 and R13). New Zealand White growing rabbits were used from weaning to slaughter (70 d old), to analyse mortality, morbidity, performance, intake behaviour, digestion and microbial activity. Seven days after starting feed restriction (35 d old, group R1), rabbits consumed 44% of the feed within 2 h, 65% in 4 h and in 7 h over 95%. Over the 28–70 d period, mortality was low (5.3%) while morbidity averaged 18.5% and neither was affected by treatment. However, FFD tended to decrease the morbidity rate during the first 14 days after weaning (P = 0.06). Feed conversion (28–70 d) was improved by restriction (+15%, P < 0.001) and by FFD (+5%, P < 0.001). Nutrient digestibility was improved by restriction (+10% for energy, P < 0.01), but not by FFD. Fragmented feed distribution led to a lower stomachal pH, in the antrum (1.48 vs 2.13, P < 0.001) and in the fundus (1.52 vs 2.63, P < 0.001), while a higher pH was found in the caecum (6.07 vs 5.86, P < 0.001). Butyrate proportion in the caecum was reduced by four units for restricted groups. Fragmented feed distribution reduced the caecal VFA concentration by 23% within restricted rabbit groups only. A similar interaction between intake level and FFD was observed for fibrolytic activity (cellulase and xylanase). The diversity of caecal bacterial community was not modified by either of the two factors studied. Globally, fragmented meals have no major impacts on the caecal microbial activity, diversity, and thus would not be implicated in the better resistance of restricted rabbit to digestive troubles.     

Part-time grouping of rabbit does in enriched housing: effects on performances,injury occurrence and enrichment use

Collective housing is perceived as a possible way to improve rabbit welfare, especially among adult females, which are normally individually housed. Part-time group housing seems to allow a better balance between welfare and health than continuous group housing, but practical implementation and consequences for reproductive performance have not been extensively studied. The aim of this work was to compare weight, feed intake, litter size, injury occurrence, body integrity, and spatial location of female rabbits housed part-time in group housing (PGH group, n = 32) or housed individually (IH group, n = 8). Females were grouped by opening connecting hatches between four individual enriched cages (platform, wood stick and gnawing block). Collective housing started 12 days after artificial insemination and was interrupted at the 10th day (instead of the 15th day later as originally planned) due to high injury rates and severe injuries caused by fighting. The proportion of injured females increased from 25% on the first day of grouping to 63% on the 10th day. Female weight gain during the experiment was similar in the two groups. Litter size at weaning was 9% lower in the PGH group than in the IH group (9.2 vs 10.0, P < 0.01). Platform use was recorded in 32% of the observations and was the highest during the 2 weeks before weaning (46% and 47% of total observations, P < 0.05). During the grouping period, there were at least two females in the same housing unit in 59.4% of the cases, at least two females were located on the same level in 31.3% of the cases. In conclusion, connecting individual cages is an ergonomic solution for part-time group housing, but does not prevent fights for the establishment of a social hierarchy. This is detrimental to the health and body integrity of female rabbits.     

Intake,milk yield and grazing behaviour of strip-grazing Alpine dairy goats in response to daily pasture allowance

Grazing management has an important impact on dairy ruminants’ performance. References on the intake and milk yield of dairy goats under strip-grazing systems in temperate regions are scarce. In order to study the effect of pasture allowance on pasture intake (PI), milk yield and grazing behaviour, a trial was carried out in spring with 36 Alpine goats in mid-lactation. Three daily pasture allowances (PA=1.7, 2.6 and 3.5 kg dry matter (DM)/day, namely Low, Medium and High, respectively) were compared in a 3 × 3 Latin square design replicated six times during three successive 14-day periods. Goats individually received 268 g DM of concentrate twice daily at each milking and had access 11 h/day to pasture (from 0830 to 1600 h and from 1730 to 2100 h). Pasture intake increased with PA, and more so between Low and Medium than between Medium and High (+216 v. +101 g DM/kg DM of PA). Milk yield was lower on Low than on Medium and High (2.79 v. 3.13 kg/day), as were milk fat and protein yields. Grazing time averaged 476 min/day and was lowest on Low and greatest on Medium. Pasture intake rate was 30 g DM/h lower on Low and Medium than on High. It is concluded that under temperate conditions, when goats are supplemented with 536 g DM of concentrate and have enough access time to pasture (11 h/day), a medium pasture allowance close to 2.6 kg DM/day may be sufficient to maximise milk yield.     

Effects of supplemental fat sources and forage feeding levels on growth performance,nutrient digestibility,ruminal fermentation,and nitrogen utilization in dairy calves

Knowledge regarding the potential interactions between supplemental fat source and fiber level in starter diet of dairy calves is lacking. The aim of the present study was to investigate the effects of supplemental saturated fat [palm fat (PLF) containing 86% palmitic acid (C16:0)] vs. unsaturated fat [soybean oil (SBO) containing 51% linoleic acid (C18:2)] and forage level on feed intake, growth performance, ruminal fermentation, nutrient digestibility, and metabolic traits in dairy calves. Forty newborn Holstein female calves (BW = 39.7 ± 1.8 kg) were assigned to 1 of 4 treatment groups (each consisting of 10 animals) in a 2 × 2 factorial arrangement of fat source [soybean oil vs. palm fat; 3% of starter based on DM basis] and alfalfa hay level (0 vs. 15%, on DM basis): SBO or PLF with (AH) or without (NAH) alfalfa hay. Calves had ad libitum access to water and starters throughout the study and a constant amount of milk was offered among experimental calves during the pre-weaning period. All calves were weaned on day 63 of age and remained in the study until day 73 of age. The results showed that the lowest and the highest starter intake and average daily gain during pre-weaning period was observed when calves received SBO-AH and PLF-AH, respectively. Accordingly, the lowest wither and hip heights at weaning time (day 63) and final wither height (day 73) were observed in SBO-AH group across treatments. Calves received PLF-AH had the highest weaning and final BW compared to other groups. Feed efficiency tended to be higher in PLF groups compared with SBO calves. Calves fed SBO-AH had the lowest digestibility of organic matter and neutral detergent fiber and also total short chain fatty acid concentrations in rumen compared with other groups. The SBO calves had lower urinary allantoin, urinary purine derivatives, and microbial protein synthesis than PLF calves; however, urinary nitrogen increased with SBO supplementation. In summary, the supplementation of SBO rich in C18:2 and AH during the pre-weaning period resulted in negative responses on growth performance, digestibility, and ruminal fermentation profile. Therefore, the inclusion SBO rich in C18:2 along with forage in the starter is not recommendable for young dairy calves.     

Effects of forage quantity and access-time restriction on feeding behaviour,feed efficiency,nutritional status,and dairy performance of dairy cows fed indoors

Optimising feed is a key challenge for dairy livestock systems, as forage stock shortages are increasingly frequent and feed is the biggest operating cost. The aim of this experiment was to evaluate the effects of reducing forage quantity and access time on dairy performance and animal nutritional status during indoor feeding. Twenty-seven Montbéliarde and Holstein cows were randomly allocated to three groups of nine cows balanced by breed, parity, days in milk, and milk yield. The three groups were given 3.9 kg DM/day of second-cut hay and 4.5 kg/day of concentrate and either i) ad libitum access to first-cut hay (Ad Libitum group; AL), ii) 10.5 kg/day of first-cut hay (Quantity-restricted group; QR), or iii) 10.5 kg/day of first-cut hay but with access time restricted to only 2 h in the morning and 2 h in the afternoon (Quantity-and-Time-restricted group; QTR). Milk yield, composition and coagulation properties, cow nutritional status (weight, body condition score, blood metabolites) and cow activities were recorded. The AL group ingested 10 % more feed than the QR group and 16 % more feed than the QTR group. Organic matter digestibility was lower in the AL group than in the QR and QTR groups whereas feed efficiency did not differ. Milk yield was not significantly different among the three groups. Compared to the QR and QTR groups, the AL group had significantly higher milk fat (35.9 vs 32.9 and 32.8 g/kg of milk) and milk protein content (29.5 vs 27.7 and 28.5 g/kg of milk). QR and QTR cows mobilised their body fat, resulting in a lower final body condition score, and tended to have a lower blood non-esterified fatty acid concentration than the AL group. QTR cows showed greater body fat mobilisation, but their final corrected BW was not different from AL cows. Access-time restriction did not impact fat and protein content but led to decreased casein, lactose contents and casein-to-whey protein ratio. The forage savings achieved through this feed management practice could prove economically substantial when forage prices increase. This practice can be of interest in grassland systems to overcome certain climatic hazards without having to resort to purchases or to increase the farm's forage autonomy.     

Health Behaviours and Potentially Preventable Hospitalisation: A Prospective Study of Older Australian Adults

Objective

Several studies have demonstrated the effects of health behaviours on risk of chronic diseases and mortality, but none have investigated their contribution to potentially preventable hospitalisation (PPH). We aimed to quantify the effects on risk of PPH of six health behaviours: smoking; alcohol consumption; physical activity; fruit and vegetables consumption; sitting time; and sleeping time.

Design/Setting

Prospective observational study in New South Wales, Australia.

Subjects

267,006 men and women aged 45 years and over.

Outcome Measures

PPH admissions and mortality during follow-up according to individual positive health behaviours (non-smoking, <14 alcoholic drinks per week, ≥2.5 hours of physical activity per week, ≥2 servings of fruit and 5 servings of vegetables per day, <8 hours sitting and ≥7 hours sleeping per day) and the total number of these behaviours.

Results

During an average of 3 years follow-up, 20971 (8%) participants had at least one PPH admission. After adjusting for potential confounders, participants who reported all six positive health behaviours at baseline had 46% lower risk of PPH admission (95% CI 0.48–0.61), compared to those who reported having only one of these behaviours. Based on these risk estimates, approximately 29% of PPH admissions in Australians aged 45 years and over were attributable to not adhering to the six health behaviours. Estimates were similar for acute, chronic and vaccine-preventable categories of PPH admissions.

Conclusions

Individual and combined positive health behaviours were associated with lower risk of PPH admission. These findings suggest that there is a significant opportunity to reduce PPH by promoting healthy behaviours.     

Design,synthesis and evaluation of 2-(indolylmethylidene)-2,3-dihydro-1-benzofuran-3-one and 2-(indolyl)-4H-chromen-4-one derivatives as novel monoamine oxidases inhibitors

A series of 2-(indolylmethylidene)-2,3-dihydro-1-benzofuran-3-ones (aurone-indole hybrids) and 2-(indolyl)-4H-chromen-4-ones (flavone-indole hybrids) were designed, synthesized, and their monoamine oxidase (MAO) A and B inhibitory activities were evaluated. Compounds 5b and 11b showed potent inhibitory activities against MAO-A, comparable to that of pargyline used as a positive control, and most of the compounds, except for 2a and 10b, showed potent inhibitory activities against MAO-B. Compound 9a was the most potent and highly selective inhibitor of MAO-B (IC₅₀ value for MAO-B: 0.0026 μM, and MAO-A: >100 μM). Comparison of the inhibitory activities of 1a vs. 9a vs. 13a and 1b vs. 7b vs. 11b suggested that methoxy substitution at R¹ on the A-rings of flavonoids increases MAO-A inhibition whereas methoxy substitution at R² increased MAO-B inhibition. Comparison of 4a vs. 10a, 6a vs. 11a, 3b vs. 8b and 4b vs. 9b showed incremental increases in MAO-B inhibitory activity by R² substitution on the A ring. Comparison of the MAO-B inhibitory effects of the flavone-indole hybrids and aurone-indole hybrids showed that most of the aurone-indole hybrids were stronger inhibitors than the corresponding flavone-indole hybrids. Molecular docking analysis of compounds 1a and 9a with MAO-B further supported the above structural effects of these compounds on MAO-B inhibitory activity.This is the first report identifying aurone-indole hybrids as potent MAO-B inhibitors. The results reported here suggest that 2-(1H-indol-1-ylmethylene)-6-methoxy-3(2H)-benzofuranone (9a) might be a useful lead for the design and development of novel MAO-B inhibitors     

A 3-week feed restriction after weaning as an alternative to a medicated diet: effects on growth,health, carcass and meat traits of rabbits of two genotypes

Feed restriction after weaning is widely used in meat rabbit farms to promote health and reduce mortality, but this practice impacts negatively on rabbit growth and slaughter performance. This study compared a 3-week post-weaning feed restriction with ad libitum medicated feeding, evaluating effects on feed intake, growth, health, carcass and meat quality of rabbits of two genotypes: Italian White pure breed and Hycole hybrid×Italian White crossbred. A total of 512 rabbits at 36 days of age, of both sexes and two genotypes, were divided into four homogeneous groups assigned, from 36 to 57 days of age, to different feeding programmes (FP): restricted non-medicated (R-N), ad libitum non-medicated (L-N), restricted medicated (R-M) and ad libitum medicated (L-M). The diets were medicated with oxytetracycline (1540 mg/kg) and colistin sulphate (240 mg/kg). The restriction, performed by giving 70, 80 and 90 g/day of feed for the 1st, 2nd and 3rd week, was followed by ad libitum feeding in the successive 5 weeks, up to slaughter at 92 days of age. Restricted feeds were ingested at a level of 64% of the feed intake recorded in the ad libitum fed rabbits; it was significantly associated, regardless of medication and rabbit genotype, with a lower feed intake (−22 to −24 g dry matter/day) during the entire experiment, compensatory growth and a lower feed conversion ratio in the ad libitum period, and a lower final live weight (−150 g) than ad libitum feeding (P<0.001). During restriction, mortality was lower in the restricted rabbits (6.25%, 5.47% v. 12.5%, 14.8% for R-N, R-M, L-N and L-M; P<0.05), whereas in the ad libitum period mortality did not differ among the groups (9.23%, 9.90%, 11.0% and 4.59% for R-N, R-M, L-N and L-M). Dressing out percentage was not affected by FP or genotype; heavier carcasses were produced by rabbits fed ad libitum (+100 g; P<0.001) and crossbred rabbits (+122 g; P<0.001). Restriction did not alter meat quality, except for a tendency towards a higher cooking loss and less fat; crossbred meat was higher in L* (+1.3; P<0.01) and b* (+0.51; P<0.05) colour indexes and tenderness (−0.14 kg/cm²; P<0.05) than pure breed meat. Under the conditions of this study, a 3-week restricted feeding after weaning resulted to be a suitable alternative, also for high growth potential genotypes, to the antibiotics to preserve rabbit health. The production of lighter carcasses could be compensated partly by the lower feed conversion ratio showed by restricted rabbits.     

Design,synthesis and biological evaluation of novel 1,2,3-triazole linked coumarinopyrazole conjugates as potent anticholinesterase,anti-5-lipoxygenase,anti-tyrosinase and anti-cancer agents

A series of new 1,2,3-triazole linked coumarinopyrazole conjugates 4a-e and 5a-e have been synthesized via the Copper(I)-catalysed Alkyne-Azide Cycloaddition (CuAAC). Going through the reaction of compound 2 with the 3-propargyl bromide gave a mixture of propargylated regioisomers 3 + 3′ used as a dipolarophile to access to triazoles 4a-e and 5a-e. The structures of the prepared cycloadducts were determined by ¹H, ¹³C and 2D-NMR techniques and by HRMS analysis. All the synthesized derivatives have been evaluated for their anticholinesterase, anti-5-lipoxygenase, anti-tyrosinase, and cytotoxic activities.     

Sterols,aromatic compounds,and cerebrosides from the Hericium erinaceus fruiting body

Chemical investigation of the methanolic extract from the fruiting bodies of Hericium erinaceus, led to the isolation of fifty-one compounds including thirty-five ergostane-type sterols (1–35), fourteen aromatic compounds (36–49), and two cerebrosides (50 and 51). Their structures were identified based on spectroscopic analyses and by comparison of their spectral data with those reported in literature. This is the first comprehensive low-polarity chemical investigation of H. erinaceus. Thirty-one of the compounds (6–8, 11–35, 39, 41, and 49) were isolated for the first time from the genus Hericium and the family Hericiaceae. The chemotaxonomic relationship between H. erinaceus and other Hericium species was also discussed.     

Nitric oxide-donating carbonic anhydrase inhibitors for the treatment of open-angle glaucoma

Novel bi-functional compounds with a nitric oxide (NO)-releasing moiety bound to a dorzolamide scaffold were investigated. Several compounds were synthesized and their activity as selective carbonic anhydrase inhibitors (CAI) evaluated in vitro on recombinant hCA type I, II and IV enzyme isoforms where they showed different degrees of potency and selectivity to hCA II. A high resolution X-ray crystal structure for the CA II adduct with 8 confirmed the high affinity of this class of compounds for the enzyme. Compounds 4, 6, and 8 showed highly potent and efficacious NO-mediated properties as assessed by their vascular relaxant effect on methoxamine-precontracted rabbit aortic rings. Finally, compounds 4 and 6 exerted potent intraocular pressure (IOP) lowering effects in vivo in normotensive rabbits thereby anticipating their potential for the treatment of hypertensive glaucoma.     

Performance,health, and physiological responses of newly received feedlot cattle supplemented with pre- and probiotic ingredients

Nutritional strategies that optimize immunity of feedlot cattle are warranted due to increasing regulations with the use of feed-grade antimicrobials. This study evaluated physiological, health, and performance responses of cattle receiving a synbiotic supplement (yeast-derived prebiotic + Bacillus subtilis probiotic), which replaced feed-grade antimicrobials or were fed in conjunction with monensin during the initial 45 days in the feedlot. Angus-influenced steers (n = 256) were acquired from an auction facility on day −2, and transported (800 km) to the feedlot. Shrunk BW was recorded upon arrival (day −1). Steers were allocated to 1 of 18 pens (day 0), and pens were assigned to receive (n = 6/treatment) a free-choice diet containing: (1) monensin and tylosin (RT; 360 mg/steer daily from Rumensin and 90 mg/steer daily from Tylan; Elanco Animal Health, Greenfield, IN, USA), (2) yeast-derived ingredient and B. subtilis probiotic (CC; 18 g/steer daily of Celmanax and 28 g/steer daily of Certillus; Church and Dwight Co., Inc., Princeton, NJ, USA), or (3) monensin in addition to yeast-derived and B. subtilis ingredients (RCC) as in RT and CC. Steers were assessed for bovine respiratory disease (BRD) and DMI daily. Steer BW was recorded on days 45 and 46, and averaged for final BW. Blood samples were collected on days 0, 7, 17, 31, and 45. Feed intake was greater (P ≤ 0.05) in CC vs. RCC and RT during the initial 3 weeks upon feedlot arrival. No treatment differences were noted (P ≥ 0.41) for average daily gain, BW, and feed efficiency. Incidence of BRD did not differ (P = 0.77) between treatments (average 80.1%). A greater proportion (P ≤ 0.03) of RT steers diagnosed with BRD required a second antimicrobial treatment compared with CC and RCC (57.3, 37.3, and 38.6%, respectively). Removal of steers from the trial due to severe morbidity + mortality was greater (P = 0.02) in RT vs. CC (22.4 and 7.0%), and did not differ (P ≥ 0.16) among RCC (12.9%) vs. RT and CC. Plasma glucose concentrations were greater (P ≤ 0.02) in CC vs. RCC and RT on day 7. Plasma concentrations of nonesterified fatty acids were greater (P ≤ 0.02) in RT and RCC vs. CC on day 7, and in RT vs. CC on day 17. Steers receiving the synbiotic supplement had improved response to BRD treatment, suggesting heightened immunocompetence from partially enhanced metabolism and the nutraceutical effects of B. subtilis and yeast compounds.     

The effects of farrowing nest size and width on sow and piglet behaviour and piglet survival

The ‘Werribee farrowing pen' (WFP) was developed as a loose housing alternative to the farrowing crate. The WFP occupies about twice the space of a crate and comprises two compartments, a ‘nest' and a ‘non-nest' area. In this experiment, we investigated the effects of reducing total pen space by modifying the dimensions of the ‘nest'. The hypothesis was that modifying ‘nest' size and width would not negatively affect piglet survival. A reduction in total floor space in the WFP may increase attractiveness for adoption of the system by pig producers. The experiment had a 2×2 factorial design with nine replicates and a total of 72 primiparous sows (Large White×Landrace) and their litters. All subjects were included to day 4 of lactation, but production data to weaning (day 23) was restricted to 36 litters. We examined the effects of ‘nest' size (large: L vs. small: S) and width (wide: W vs. narrow: N) on sow and piglet behaviours and piglet survival. The W, as compared to N treatment sows, had longer mean bouts of standing in the ‘nest' during 16–8 h pre-farrowing (3.7 vs. 2.0 min, P<0.01), suggesting that pre-farrowing (‘nesting') behaviour may have been adversely affected by narrow nest width. On the first 2 days of lactation, sow suckling grunts occurred more in the W than N treatment (14.1 and 8.0% of observations, P<0.01). However, this was due to an approximately 50% lower incidence in the SN treatment, as compared to the other treatments combined (5.9 and 12.7%). Piglets spent more (P<0.01) time at the udder in L vs. S (41 and 30%) and W vs. N nests (40 and 31%) and performed more (P<0.05) sucking behaviour (i.e., drinking milk from a teat) in L vs. S nests (2.5 and 1.2%). These differences were due to SN treatment litters sucking less than other treatments combined (0.9 vs. 2.2%). Of the 680 piglets born (n=72 litters), 3.8% were stillborn and 6.8% died between birth and day 4 of lactation. From day 5 to weaning (n=36 litters), 3.5% of piglets died, all due to Escherichia coli infection. While there were no effects of treatment on piglet survival, liveborn piglets were less likely (P<0.05) to die from E. coli in the L vs. S treatments (9/24 vs. 23/33 piglets). In conclusion, our results provide evidence that the size and width of the farrowing ‘nest' in a loose farrowing system may effect sow and piglet behaviours that may be relevant to piglet survival.     

An unusual lanostane-type triterpenoid,spiroinonotsuoxodiol, and other triterpenoids from Inonotus obliquus

An unusual lanostane-type triterpenoid, spiroinonotsuoxodiol (1), and two lanostane-type triterpenoids, inonotsudiol A (2) and inonotsuoxodiol A (3), were isolated from the sclerotia of Inonotus obliquus. Their structures were determined to be (3S,7S,9R)-3,7-dihydroxy-7(8 → 9)abeo-lanost-24-en-8-one (1), lanosta-8,24-dien-3β,11β-diol (2), and (22R)-3β,22-dihydroxylanosta-8,24-dien-11-one (3) on the basis of NMR spectroscopy, including 1D and 2D (¹H–¹H COSY, NOESY, HMQC, HMBC) NMR, and FABMS. Compounds 1–3 showed moderate activity against cultured P388, L1210, HL-60 and KB cells.     

Anti-inflammatory,antimicrobial and acetylcholinesterase inhibitory activities of friedelanes from Maytenus robusta branches and isolation of further triterpenoids

The new pentacyclic triterpenoids friedel-1-en-3,16-dione (1), 1α,29-dihydroxyfriedelan-3-one (2) and 16β,28,29-trihydroxyfriedelan-3-one (3) were isolated from Maytenus robusta branches in addition to the known, but new for this species, triterpenoid 12α,29-dihydroxyfriedelan-3-one (4). The structures and stereochemistry of the novel triterpenoids were established by IR, 1D/2D NMR and HR-APCIMS spectral data. In addition, the biological activity of compound 2 and the previously isolated friedelanes 5–8 (friedelan-3,16-dione, 29-hydroxyfriedelan-3-one, 29-hydroxyfriedelan-3,16-dione and 16β,29-dihydroxyfriedelan-3-one) was investigated. Compounds 2 and 8 were tested for their acetylcholinesterase properties and antimicrobial activity against the bacteria Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes, Citrobacter freundii, and the fungus Candida albicans. Compound 2 was the most active compound for both assays, with values of 32.3% acetylcholinesterase inhibition, 42% activity against the fungus Candida albicans and 34% against the bacterium Pseudomonas aeruginosa. Compounds 5–8 were assayed for their antiedematogenic activity using the carrageenan-induced paw edema assay. At maximum inflammation after three hours, compounds 6 and 8 showed 42% and 57% activity, respectively. After four hours, compounds 5 and 7 showed activity of 71% and 75% compared to 79% of the control indomethacin.     

PASTRAB: a model for simulating intake regulation and growth of rabbits raised on pastures

Given the very recent investment in research on organic rabbit production, many knowledge gaps remain. Simulation models based on data from experiments and farms may help generate general principles for organic rabbit production. Our goals were to (i) develop a model to simulate intake regulation and growth of rabbits raised on pastures, (ii) validate this model under a diversity of conditions and (iii) conduct a simulation experiment to predict the potential to decrease the supply of complete feed by increasing the grazing area per rabbit. The model developed (PASTRAB) simulates organic rabbit fattening on pastures in four main submodels that represent dynamics of (i) herbage standing biomass, fill and feed values; (ii) intake of herbage, complementary feed (i.e. complete pellets, cereal–legume grain mixtures) and hay as regulated by herbage allowance, fill and feed values of feedstuffs and rabbit physiological parameters; (iii) conversion of rabbit intake into live weight gain; and (iv) rabbit mortality. The model also calculates gross margin per rabbit sold. Model accuracy was assessed by considering the fit between observed and predicted herbage intake, which was low, with a relative root mean square error (rRMSE) of 51% and 66% on grass-based and legume-based pastures, respectively. However, the standard deviations of observed herbage intake were similar to the root mean square error of predicted herbage intake, indicating that it would have been difficult to improve model calibration. The fit between observed and predicted rabbit live weight was acceptable, with an rRMSE of 11% and 10% for grass-based and legume-based pastures, respectively. Simulated scenarios showed that a decrease in complementary feed combined with an increase in the grazing area per rabbit had little impact on average daily growth and gross margin per rabbit but increased herbage use efficiency. With 90 g of complementary feed per day and grazing of 0.4 m²/rabbit per day, herbage use efficiency was 22%, with average daily growth of 21.6 g/day and gross margin of 18.80 €/rabbit. With no complementary feed and grazing of 1.2 m²/rabbit per day, average daily growth decreased (19.2 g/day), but herbage use efficiency reached 100% and gross margin reached 19.20 €/rabbit. We used PASTRAB in participatory workshops with farmers so that the latter could explore adaptations to their current practices. Overall, farmers considered the model predictions realistic, and some of them decided to adapt some of their management practices immediately after the workshops.