Effect of oat decortication on chemical composition,in vitro digestibility and in situ degradability

The effect of decortication on chemical composition and degradability characteristics of four Danish oat varieties was investigated. Effective degradability (ED) and post-ruminal disappearance (PRD) were measured by in situ and mobile bag techniques respectively. Decorticated oat showed higher (p = .01) concentrations of crude protein (CP; 134 vs. 108 g/kg DM) and crude fat (71.6 vs. 53.1 g/kg DM) and a higher (p = .001) organic matter digestibility (OMD; 888 vs. 703 g/kg OM) than oat. The content of total fatty acids (FA) in DM was higher in decorticated oat. The proportion of linoleic acid (C18:2 n6) increased (p < .05) due to decortication, while the linolenic acid (C18:3 n3) proportion of total FA decreased in decorticated oat. Decortication increased (p = .01) the concentration of amino acids (AA), but the proportion of lysine in total AA decreased (p < .002). Effective degradability (ED) of both DM and CP was (p < .001) higher in decorticated oat. Decortication increased the total tract disappearance (TTD) and PRD of CP (p < .001). In conclusion, decortication can be used as a practical approach to increase the nutritional value of oat.     

In sacco evaluation of ruminal degradability of isoflavones from full-fat soybean and extracted soybean meal—A pilot study

The aim of the study was to determine the ruminal degradability of dry matter (DM), daidzein, genistein, glycitein and total isoflavones in ground full-fat soybean (GFFS) and solvent-extracted soybean meal (SSBM) using the in sacco method. The experiment was carried out in three replications on ruminally cannulated sheep that were fed twice a day with a diet consisted of hay and supplemental mixture (6:4, DM basis). The nylon bags with 2 g feed samples ground to 2 mm were incubated in the rumen for 0, 2, 4, 8, 16 and 24 h. The effective degradability (ED) of DM, daidzein, genistein, glycitein and total isoflavones was calculated at outflow rate of 0.06 h. The ED of DM in GFFS was 77.8% and was higher than in SSBM being 71.8% (p < 0.001). The ED of daidzein (96.8%) and genistein (93.6%) was higher for SSBM compared with GFFS (93.9% and 92.8%, p < 0.001 and p = 0.003, respectively) while ED of glycitein was lower for SSBM than for GFFS (75.5 and 81.7%, respectively, p < 0.001). All isoflavones in the incubations were extensively degraded in the rumen, and regardless of dietary source, they were almost completely degraded after 16 h of incubation. Further, the disappearance patterns, that is the functions describing the time courses of the analyte disappearance, were assessed. The disappearance patterns of daidzein, genistein, glycitein and total isoflavones were similar and showed greater disappearance of mentioned isoflavones from SSBM compared to GFFS (p < 0.001 for daidzein, genistein and total isoflavones and p = 0.002 for glycitein). The study provides knowledge on the effect of processing on degradability of isoflavones in rumen that can be used to clarify the interrelationship between isoflavones and rumen microbiota.     

Influence of harvesting site on chemical composition and potential protein value of Acacia erioloba,A. nilotica and Ziziphus mucronata leaves for ruminants

This study was designed to evaluate the chemical composition, buffer N solubility, in vitro ruminal N degradation and in vitro ruminal biological activity of condensed tannins in Acacia erioloba, Acacia nilotica and Ziziphus mucronata leaves harvested from two sites (Masuthle communal grazing land and Molelwane private farm). Leaves were harvested, dried at 60 °C and milled. The highest crude protein (CP) content was found in leaves of Z. mucronata (177.7 g/kg DM). Leaves harvested from Masuthle had higher (p < 0.05) soluble phenolics (SPh) (44.6 g TAE/kg DM) compared to those harvested from Molelwane (29.8 g TAE/kg DM). In both Molelwane and Masuthle, leaves of A. nilotica had higher levels of condensed tannins (CT) (0.76 AU_550/200 mg and 0.52 AU_550/200 mg respectively) followed by A. erioloba and Z. mucronata, which did not differ (p > 0.05). Nitrogen degradability at 24 h was the same (p > 0.05) for all tree species but not at 12 and 36 h. No linear association (p > 0.05) was found between buffer‐soluble N and in vitro ruminal N degradability in leaves with high SPh content. The largest polyethylene glycol (PEG) effect was in leaves of A. nilotica (448%) harvested from Masuthle after 36 h of incubation. Ziziphus mucronata leaves harvested from Molelwane had the least PEG effect at 48 h. There was no linear association (p > 0.05) between PEG effect and SPh for all incubation periods, but a positive relationship was observed between PEG effect and condensed tannins content. There was no linear association between solubility index (SI) and in vitro ruminal N degradability for tannin‐rich leaves. It was concluded that higher browsing pressure in Masuthle communal rangeland resulted in leaves with higher levels of condensed tannins, which had higher in vitro ruminal biological activity, compared to those harvested from Molelwane.     

Effect of adding crude glycerine to diets with feed additives on the feed intake,ruminal degradability,volatile fatty acid concentrations and in vitro gas production of feedlot Nellore cattle

The effects of adding crude glycerine with sodium monensin or essential oils to beef cattle diets on the intake, degradability of DM and nutrients, rumen concentration of volatile fatty acids (VFA) and in vitro gas production were evaluated. Five ruminally cannulated Nellore steers were randomly assigned to a 5 × 5 Latin square design. The treatments were as follows: CONT, without crude glycerine and additives; EO, with essential oils and without crude glycerine; MON, with sodium monensin and without crude glycerine; EOG, with essential oils and crude glycerine; MONG, with sodium monensin and crude glycerine. Treatments with essential oil and sodium monensin increased the NDF and STC intake and the DM degradability. When crude glycerine was combined with either sodium monensin or essential oil, there was a reduction in DM, NDF and STC intake and an increase in DM and CP degradability of the diets. The adding crude glycerine to essential oil diets reduced the CH₄ production. Sodium monensin treatments reduced DM and NDF intake and the production of total gas, CH₄, total VFA and acetic acid concentration. In conclusion, the adding crude glycerine (200 g/kg DM) with either sodium monensin (0.03 g/kg DM) or essential oil (0.5 g/kg DM) can be utilized in diets for Nellore cattle without causing detrimental effects on feed intake and improving the DM degradability.     

Fattening performance,slaughter, carcass and meat quality traits of Karayaka lambs

In order to verify the fattening performance, slaughter and carcass characteristics and to investigate the changes in some meat quality traits of Karayaka lambs weaned at 3 months of age, 39 lambs (23 males and 16 females) were used as experimental animals. The lambs were fed a concentrate mixture and alfalfa hay (120 and 168 g crude protein and 2,700 and 1,951 ME/kg, respectively) for a period of 60 days of fattening period. Male lambs were superior (p < 0.05) to female lambs in terms of daily weight gain (270.4 vs. 205.4 g; SEM = 9.46), hot and cold carcass weights (16.7 and 16.0 vs. 14.1 and 13.4 kg, respectively; SEM = 0.35), intra-muscular fat ratios (1.9% vs. 2.5%; SEM = 0.12) and dripping loss of semitendinosus muscle 3 days postmortem (8.1% vs. 10.2%; SEM = 0.36). The relative weights of some organs, the meat quality traits (pH, cooking loss, shear force, CIELab colour characteristics) and proximate analyses (dry matter, protein and ash) of longissimus dorsi and semitendinosus muscle samples from lambs were not affected by sex (p > 0.05). Dripping loss, pH and colour characteristics were affected by storage time (p < 0.05). These results provide a basic understanding of performance and meat quality of Karayaka sheep which may have potentials in improving sheep production using an indigenous sheep breed in Turkey.     

Effect of semen extenders and storage time on quality of Muscovy duck (Cairina moschata) drake semen during the entire reproductive season

Avian semen dilution with appropriate extender allows to prolong the fertilizing ability of sperm stored in vitro. In the present study, the impact of extenders and time of storage on morphology of Muscovy duck (Cairina moschata) drake semen were examined. Semen was collected twice a week, using male stimulation by a female method, from 12 adults (29 weeks old) drakes kept individually in cages, under controlled environmental conditions. Freshly collected, pooled ejaculates were divided into three part: neat undiluted sample, and diluted 1:1 with Schramm (SCH) or Watanabe (W) extender and stored at 4°C. Morphological examination of all samples was conducted after dilution and then, after 3 and 6 hr of storage. The storage of undiluted semen caused decrease (p ≤ .01) in live morphologically normal sperm, from 79.73% in the freshly collected ejaculates to 55.75% and to 12.12% after 3 and 6 hr of storage, respectively (average calculated for the entire reproductive season). In the semen diluted with Schramm's extender the adequate values attained 86.84, 79.65 and 61.66%, and using Watanabe extender 84.77, 83.58 and 75.25%, respectively. The period of semen storage and the type of extender caused significant (p ≤ 0,05; p ≤ 0,01) changes in sperm morphology. The longer period of storage contributed to the decrease in number of morphologically normal sperm, whereas their content in Watanabe extender after 3 and 6 hr of storage was higher (p ≤ .01) than in semen diluted in Schramm extender.     

Dose response of rumen‐protected conjugated linoleic acid supplementation to fattening bulls and heifers on growth,and carcass and meat quality

We investigated the influence of rumen‐protected conjugated linoleic acid (rpCLA) on growth performances, and carcass and meat quality traits in beef. Twenty‐four young bulls and 30 heifers obtained from double‐muscled beef sires and dairy cows were fed a low‐protein ration (110 g/kg DM of crude protein) supplemented with 0, 8 or 80 g/d of a commercial rpCLA product. The animals were monthly weighed and scored for body muscularity and fatness. Blood samples were collected after 140 days on feed. Animals were slaughtered when they reached average in vivo fatness scores of around 2.5 (heifers) and 2.0 (bulls) points respectively. At slaughter, carcasses, various organs and parts of the gastrointestinal tract were weighed; the 5th rib was dissected and its tissue and muscle chemical composition was determined. The rpCLA had little influence on growth performance but decreased the blood urea content by 28% (p < 0.01). The rpCLA × sex interactions for daily gain (p < 0.05), conformation scores (p < 0.01), and blood creatinine content (p < 0.05) suggest that males were more responsive to rpCLA than females when fed a low‐protein ration, probably because of the metabolic protein‐sparing effect of CLA. Only slight differences were observed in carcass weight and quality at slaughter. The results indicate that the response of beef cattle to rpCLA is dependent on sex or on their propensity for lean and fat accretion. It is also possible that counteracting feedback mechanisms compensate for the influence of rpCLA administration over the course of growth.     

Dry Matter and Crude Protein Degradability of Four Parasitic Plants (Mistletoes) Associated with Browse Trees in Botswana

Four parasitic plants (Tapinanthus lugardii, Erianthenum ngamicum, Viscum rotundifolium and Viscum verrucosum) associated with browse trees in Botswana were evaluated for the degradability of their dry matter (DM) and crude protein (CP). All these plants have high levels of crude protein, ranging from 144.5 to 163.4 g/kg DM, with a significant (p<0.001) difference in crude protein content between the plants. The rate of degradation of DM was highest for V. rotundifolium (0.197 h⁻¹) and lowest for E. ngamicum (0.031 h⁻¹). The two Viscum species had the highest effective DM degradability at an outflow rate of 0.05%. The rate of degradation of crude protein was highest for V. rotundifolium (0.144 h⁻¹) and lowest for T. lugardii (0.0346 h⁻¹). The effective degradability (ED) of crude protein was highest for V. rotundifolium at 0.03 and 0.05 h⁻¹ outflow rates. T. lugardii and E. ngamicum had an apparently low effective degradability, but this may result from an association of their protein with tannins, which would be able to supply amino acids in the small intestine after dissociation due to the abomasal pH. This revised version was published online in July 2006 with corrections to the Cover Date.     

Selenium supplementation improves nutrient intake and digestibility,and mitigates CH4 emissions from sheep grazed on the mixed pasture of alfalfa and tall fescue

Low selenium (Se) in soil and forage can adversely affect on the quality of animal-derived foods, and hence on human health. Lambs grazed on mixed pastures of alfalfa (Medicago sativa) and tall fescue (Festuca arundinacea) were supplemented with five levels of Se [0, 3, 6, 9 and 12 µg/kg body weight (BW)]. The intake of dry matter (DM) and organic matter (OM) varied with the level of Se supplementation, with a peak at 6 µg Se per kg BW (p ≤ 0.05). Gross energy (GE) intake, digestive energy (DE) intake and metabolic energy (ME) intake were higher at 6 µg Se per kg BW than at other Se levels (p < 0.01); in addition, methane energy (CH₄-E) output was lower at 6 µg Se per kg BW. Supplementation with Se significantly increased nitrogen (N) intake, faecal N and urine N, for which the peak values were 20.2 g N/, 5.62 g N/day and 7.92 g N/day, respectively, at 6 µg Se per kg BW. Se intake, blood Se, faecal Se, urine Se and retained Se were negatively correlated with forage crude protein (CP) content (p < 0.001) but were positively correlated with the content of neutral detergent fibre (NDF) (p < 0.001) and acid detergent fibre (ADF) (p < 0.001). Thus, we recommend the addition of 6 µg Se per kg BW to sheep grazed on pastures in regions with low soil Se.     

Effect of particle size and partial replacement of alfalfa hay by soya bean hulls on nutrient intake,total tract digestibility and rumen degradability of diets by Holstein steers

This study examined the effect of alfalfa hay (AH) particle size and the replacement of soya bean hull (SH) for AH within the diet of restricted fed Holstein steers on dry matter intake (DMI), total tract digestion, ruminal digestion, ruminal pH and ammonia nitrogen content, and faecal pH. Four rumen‐cannulated Holstein steers averaging 353 ± 9.6 kg of BW were assigned to a 4 × 4 Latin square experiment with four periods and a 2 × 2 factorial arrangement of treatments. Factor A was AH particle size (fine vs. coarse) and factor B was diet SH content (0% vs. 10%; substituted for AH). Steers were fed at 1% of body weight of TMR containing 400 g/kg forage and 600 g/kg concentrate. Chopping of AH to fine particles decreased (p = 0.01) amount of dietary materials retained on the medium sieve (8 mm). The inclusion of SH significantly increased (p = 0.01) materials retained on the 1.18‐mm sieve and tended to decrease (p = 0.07) materials on 19‐mm sieves. The inclusion of SH increased (p = 0.01) ether extract (EE) intake and increased (p = 0.07) DMI. Inclusion of SH increased (p = 0.01) EE digestion and decreased (p < 0.01) faecal pH. Neither AH particle size nor SH inclusion in diets affected (p > 0.10) the in situ ruminal degradability coefficients of DM (‘a’, ‘b’, ‘c’ or ‘a+b’). No interaction of AH×SH was seen on nutrient intake, digestibility and in situ ruminal degradability of Holstein steers.     

Comparative nutrient utilization,growth, and rumen enzyme profile of mithun (Bos frontalis) and Tho-tho cattle (Bos indicus) fed on tree-leaves-based ration

A study was conducted to compare the nutrient utilization, growth, and rumen enzyme profile of mithun (Bos frontalis) and Tho-tho cattle (Bos indicus) reared in the same feeding and managemental conditions. For the purpose, male mithun (n = 8) and male Tho-tho cattle (n = 8) of 1.5 years age, selected from the farm of National Research Centre on Mithun, Nagaland, India, were fed on mixed-tree-leaves-based ration as per the requirement of NRC (2001) for cattle for 12 months. Average daily gain (ADG), average dry matter intake (DMI), and feed conversion ratio (FCR) for all animals were recorded. A metabolic trial was conducted at 6 months of the experiment to assess the digestibility coefficient of different nutrients and nutritive value of ration. At 12 months of the experiment, rumen liquor was collected from all animals and analyzed for rumen enzyme profiles, viz., carboxymethylcellulase, xylanase, α-amylase, β-glucosidase, α-glucosidase, urease, and protease. It was found that ADG (507.8 g vs 392.8 g), DM intake (6.59 vs 5.85 kg/day) and DMI/W^0.75 (98.75 g vs 91.00 g/day), crude protein intake (780 vs 700 g/day), and total digestible nutrient intake (3.65 vs 3.32 kg/day) were higher (p < 0.05) in mithun than cattle. The nitrogen balance was higher and FCR was better (p < 0.05) in mithun compared with cattle. The digestibility coefficient of different nutrients was similar (p > 0.05) between the species. The microbial enzyme profiles of mithun and cattle were not different (p > 0.05). The better growth performance of mithun than cattle as found in the present study clearly indicates that the mithun has higher genetic potential for growth than Tho-tho cattle of north-eastern hilly region of India.     

In vitro ruminal fermentation and in situ ruminal degradation of tamarind kernel powder extract residue in wethers

We examined the in vitro fermentation characteristics and in situ dry matter (DM) and crude protein (CP) degradability of tamarind kernel powder extract residue (TKPER), a by‐product of polysaccharides thickener processing. Two types of TKPER (I and II), of which the CP and neutral detergent fiber organic matter basis contents (%) were 41.4 and 42.0 and 1.4 and 0.5, respectively, were compared with dry heat soybean (SB), soybean meal (SBM) and dry soybean curd residue (SBCR). The TKPERs had significantly lower in vitro gas production compared to the other products at each observation time (P < 0.05). The in vitro DM and CP digestibility (%) of TKPER I and II were 67.7 and 64.9, and 64.5 and 58.0, respectively, significantly lower than those of SB and SBM (P < 0.05). We used four wethers (55.6 ± 4.6 kg) with ruminal cannulas to investigate the in situ degradability of TKPER I, SB, SBM and SBCR. At the ruminal outflow rate of 0.05/h, the effective degradability (%) values of the DM and CP of TKPER I were 64.1 and 49.7, respectively, which were similar to those of SBM. In conclusion, TKPER had high CP and exhibited in situ degradability similar to that of SBM, suggesting that TKPER could be used as a protein source feed.     

Estimating purine derivatives and nitrogen compound excretion using total urine collection or spot urine samples in grazing heifers

The study aimed to evaluate the excretion of purine derivatives (PDs) and nitrogen compounds (NCs) and their ratios with creatinine in supplemented Zebu heifers kept on pastures by comparing total urine collection and spot sampling. Five Nelore heifers (400 ± 15 kg) were used in a 5 × 5 Latin square design. The treatments were the amount of concentrate (220 g of crude protein/kg dry matter) offered (0, 3, 6, 9 and 12 g/kg BW). In each period, the total urine collection was performed continuously for 3 days (subsampled at intervals of 4 h, 00:00–04:00 h, 04:00–08:00 h, 08:00–12:00 h, 12:00–16:00 h, 16:00–20:00 h and 20:00–24:00 h). The spot urine samplings were performed (in each period) for 24 h (0, 4, 8, 12, 16 and 20 h). Creatinine, total urinary nitrogen (UN), urea nitrogen (UreaN), allantoin and uric acid were analysed. Creatinine excretion was 23.01 ± 0.19 mg/kg BW and was not affected by collection day, treatment or their interactions (p > 0.05). Treatments affected (p < 0.05) PD excretions, however did not affect the ratio PD:creatinine (p > 0.05). Treatments and collection time affected (p < 0.05) NC excretion, whereas the UN:creatinine and UreaN:creatinine ratios were not affected (p > 0.05). Creatinine excretion and the PD:creatinine ratios in the urine samples estimated by the total or spot sampling were not different (p > 0.05). However, sampling method affected (p < 0.05) the UN:creatinine and UreaN:creatinine (p < 0.05) ratios. Creatinine can adequately estimate urinary excretion in grazing heifers, and a single spot urine sample at any time of the day can be used to estimate PD excretion in grazing heifers. But two spot urine samples are needed for proper NC excretion estimations in grazing heifers’ urine.     

Evaluation of microbial contamination and effects of storage in raw meat-based dog foods purchased online

Feeding raw-meat-based diets to companion animals has become a widespread practice, and many owners are now accustomed to buying frozen ingredients online. The goals of this study were to assess the microbiological quality of raw-meat dog foods obtained from specialized websites and to evaluate the effects of storage at different temperatures for a few days. Twenty-nine raw dog food products were processed for quantitative bacteriology (i.e. total viable count, TVC; Escherichia coli; faecal coliforms, FC) and sulphite-reducing clostridia, and analysed for the presence of Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica and Clostridium difficile. Every sample was examined right after the delivery (T0), after 24 to 48 hr and after 72 hr, both at 2°C and 7°C. At T0, the mean score for the TVC was 5.9 × 10⁶ cfu/g (SD = 4.8 × 10⁷ cfu/g), while those for E. coli and FC were 1.1 × 10⁴ cfu/g (SD = 2.5 × 10⁵ cfu/g) and 3.3 × 10³ cfu/g (SD = 6.5 × 10⁴ cfu/g) respectively. The samples stored at 2°C had a significant increase of all parameters (TVC: p < .01; E. coli: p = .03; FC: p = .04) through time. Noteworthy differences between the analyses performed at 2°C and 7°C were found for TVC (p < .01), being the samples considerably more contaminated at higher temperatures. No sample tested positive for Salmonella spp., while L. monocytogenes was isolated from 19 products, Y. enterocolitica from three products and Clostridium perfringens and C. difficile from four and six products respectively. The microbiological quality of raw-meat dog foods sold online appears to be poor, carrying considerable amounts of potentially zoonotic bacteria and reaching greater levels of bacterial contaminations if not kept at proper refrigeration temperatures and fed soon after defrosting.     

The effect of dietary corn oil and fish oil supplementation in dogs with naturally occurring gingivitis

The aim of this randomized, double‐blinded, placebo‐controlled study was to evaluate if downregulation of the inflammatory response due to ingestion of high levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can slow down gingivitis development, and thus delay the progression of periodontal disease (PD) in dogs. To this aim, 44 client‐owned adult dogs (>1 and <8 years old) with naturally occurring PD (stages 1 and 2) were submitted to a plaque, gingivitis and calculus scoring followed by a dental cleaning procedure and collection of blood samples. The animals were then fed a canine adult maintenance diet, supplemented with either corn oil (0.00 g EPA and 0.00 g DHA) or fish oil (1.53 g EPA and 0.86 g DHA, both per 1,000 kcal ME) over the following 5 months. At the end of this period, the PD scoring and the blood sampling were repeated. The animals consuming fish oil had higher plasma levels of the longer chain (C ≥ 20) omega 3 fatty acids (p < 0.01) and similar plasma levels of alpha‐linolenic acid (p = 0.53), omega 6 fatty acids (p > 0.63) and C reactive protein (p = 0.28) then the ones consuming corn oil. There were no differences between fish oil and corn oil diet supplementation on plaque (18.2 vs. 17.8, p = 0.78), calculus (10.1 vs. 11.5, p = 0.18) or gingivitis (19.3 vs. 19.0, p = 0.77) indexes. The authors conclude that supplementation with EPA + DHA does not slow down progression of PD in dogs.     

Chemical composition,nitrogen degradability and in vitro ruminal biological activity of tannins in vines harvested from four tropical sweet potato (Ipomoea batatas L.) varieties

This study investigated the potential of vines from four sweet potato varieties (Tia Nong 57, Tia Nong 66, Ligwalagwala and Kenya) as alternative feed resources for ruminant livestock. The chemical composition [neutral detergent fibre (NDF), acid detergent fibre (ADF), crude protein (CP) and acid detergent insoluble nitrogen (ADIN)], in vitro ruminal nitrogen (N) degradability and in vitro ruminal biological activity of tannins in the vines, harvested at 70 and 110 days after planting (DAP), were determined. Variety and harvesting stage did not (p > 0.05) influence CP and NDF content of the vines. Concentration of CP ranged from 104.9 to 212.2 g/kg DM, while NDF ranged from 439.4 to 529.2 g/kg DM across harvesting stages and varieties. Nitrogen degradability (ND) at 70 and 110 DAP was highest (p < 0.05) in Ligwalagwala (743.1 and 985.0 g/kg DM, respectively). Treatment of vines with tannin‐binding polyethylene glycol (PEG) increased (p < 0.05) in vitro ruminal cumulative gas production parameters (a, b and c). The in vitro ruminal biological activity of tannins, as measured by increment in gas production parameters upon PEG inclusion, had a maximum value of 18.2%, suggesting low to moderate antinutritional tannin activity. Ligwalagwala vines, with highly degradable N, would be the best protein supplement to use during the dry season when ruminant animals consume low N basal diets and maintenance is an acceptable production objective. Tia Nong 66 and Kenya varieties, with less degradable N, may be more suitable for use as supplements for high‐producing animals such as dairy goats.     

Variation among stallions in sperm quality after single layer centrifugation

Although single layer centrifugation (SLC) selects robust spermatozoa from stallion semen, the effect of individual variation has not been studied in detail. The objective of this study was to determine the variation among stallions in the effects of SLC on sperm quality during cooled storage for up to 48 hr. Semen samples from seven stallions (18 ejaculates) were split, with one portion being used for SLC and the other serving as a control (CON). Sperm quality (kinematics, reactive oxygen species (ROS) production, membrane integrity (MI) and chromatin integrity) were analysed at 0, 24 and 48 hr using computer-assisted sperm analysis and flow cytometry. Sperm quality was better in SLC than in CON at all timepoints, especially chromatin integrity and MI (p < .0001 for both), and some categories of ROS production (e.g. proportion of live hydrogen peroxide negative spermatozoa, p < .0001), but the degree of improvement varied among stallions and type of ROS (p < .05–p < .0001). Total and progressive motility were also better in SLC samples than in CON at 24 and 48 hr (p < .0001), although the effect on sperm kinematics varied. The interaction of treatment, time and stallion was not significant. In conclusion, sperm quality was better in SLC samples than in CON, although there was considerable individual variation among stallions. The improvement in sperm quality, particularly in chromatin integrity, was clearly beneficial, and therefore the use of this technique would be warranted for all stallion semen samples.     

Effect of olive-derived antioxidants (3,4-dihydroxyphenylethanol and 3,4 dihydroxyphenylglycol) on sperm motility and fertility in liquid ram sperm stored at 15°C or 5°C

The aim of the present study was to evaluate the effect of the addition of two olive oil-derived antioxidants, hydroxytyrosol (3,4-dihydroxyphenylethanol, HT) and 3,4-dihydroxyphenylglycol (DHPG), on ovine semen during liquid storage at 5°C and 15°C. Semen was collected, pooled, diluted and then divided into aliquots supplemented with different concentrations (5 μg/ml, 10 μg/ml, 50 μg/ml and 100 μg/ml) of HT, DHPG and a mixture (MIX) of both antioxidants. Sperm motility characteristics were assessed in the different samples at 0, 6, 24, 48, 72 and 96 hr after cooling, and a fertility trial was also conducted. The results showed that the antioxidant addition did not significantly improve total and progressive motility in ovine cooled sperm maintained at 15° or 5°C. However, in samples stored at 5°C, LIN (48, 72, 96 hr), STR (0 hr) and WOB (0, 48, 72, 96 hr) values significantly decreased in comparison with control treatment when high antioxidant concentrations were added (MIX100 or HT100). When samples were maintained at 15°C, MIX50 showed significantly higher VCL values than the control treatment after 6 hr cooling, and MIX100 showed significantly lower VCL values at 96 hr after cooling. According to the artificial insemination trial, no significant differences were observed when antioxidants were added. In conclusion, the use of HT and DHPG showed small impact in sperm motility and fertility was not affected (nor detrimentally nor positively) when insemination was carried out using antioxidant-supplemented liquid sperm.     

Feeding hay rich in water‐soluble carbohydrates improves ruminal pH without affecting rumination and systemic health in early lactation dairy cows

Forages rich in water‐soluble carbohydrates (WSC) might be an ideal energy source during early lactation, as they provide both energy for milk production and structural fibre to promote chewing and rumen buffering. Thus, the aim was to investigate feeding strategies based on high‐quality hay rich in WSC with graded amounts of concentrate on ruminating behaviour, ruminal pH and systemic health variables. Twenty‐four Simmental cows were randomly allocated to four groups beginning 10 days before until 28 days after calving. Diets were 60LQH (60% fibre‐rich hay plus 40% concentrate), 60HQH, 75HQH and 100HQH (60%, 75% and 100% high‐quality hay, plus 40%, 25% and 0% concentrate, respectively). Hay qualities differed in contents of WSC (110 g vs. 198 g of dry matter [DM]), neutral detergent fibre (646 g vs. 423 g of DM) and crude protein (65 g vs. 223 g of DM). Rumination was recorded using the Rumiwatch system over 4 days during the last week. Weekly serum samples were analysed for the liver enzymes aspartate aminotransferase, glutamate dehydrogenase and γ‐glutamyltransferase and the acute phase proteins serum amyloid A and haptoglobin. Four cows per group received a wireless pH sensor orally placed into the rumen one week before the expected calving date. Daily time spent chewing did not differ between groups. Likewise differences in minimum, maximum and mean pH‐values were not significant, but daily time of reticular pH <6 was longer in cows fed 60LQH compared to cows fed 100HQH (p = 0.043) and in tendency to cows fed 75HQH or 60HQH (p = 0.072 or p = 0.086, respectively). Blood parameters were unaffected by diet. Accordingly the present results demonstrate that feeding hay rich in WSC helped stabilizing the reticuloruminal pH in early lactation dairy cows, even in combination with 40% concentrates in DM.     

Evaluation of pigeon pea leaves (Cajanus cajan) replacing alfalfa meal on growth performance,carcass trait,nutrient digestibility,antioxidant capacity and biochemical parameters of rabbits

A 30‐day experiment was performed to determine the effect of pigeon pea leaves (PPL) on growth performance, carcass trait, meat quality, nutrient digestibility, antioxidant capacity and biochemical parameters of growing rabbits. In a completely randomized design, PPL replaced alfalfa meal at the level of 0%, 10%, 20% and 30%, which were named PPL0 (control), PPL10, PPL20 and PML30 respectively. Two hundred New Zealand white rabbits at 6 weeks with similar weight (870.23 ± 15.98 g) were allocated to four dietary groups with five replicates containing 10 rabbits/per replicate (male). The results showed that: (a) PPL powder contained 24.26% crude protein, 4.34% crude fat, 17.86% crude fibre, 7.05% ash, 1.35% calcium, 0.28% phosphorus, 1.09% lysine and 0.20% methionine, and the chemical compositions are on DM basis; (b) the ratio of feed to gain of rabbits fed diet PPL10 was significantly better (p < 0.05) than those fed other three diets; (c) the content of longissimus dorsi (LD) moisture in the rabbits fed diets without PPL (control group) was 12% lower than that in the PPL30 diets (60.1 vs. 72.1; p < 0.05). In PPL10, PPL20 and PPL30 diets, the leg muscle (LM) b*(yellowness) value was 33%, 30% and 22.6% higher than the control group respectively. The rabbits fed diets PPL0 had lower (p < 0.05) LM crude protein and ash and higher (p < 0.05) crude fat of LD and LM as compared with those fed other diets; (d) crude protein and energy digestibility of PPL0 and PPL10 diets were significantly higher (p < 0.05) than PPL30 diets; and (e) serum glutathione peroxidase (GSH‐Px) activity of the rabbits fed PPL10 and PPL30 diets was significantly higher (p < 0.05) than that fed PPL20 diets. Liver total antioxidant capacity (T‐AOC) activity of the PPL30 groups was 1.3% higher (p < 0.05) than the PPL10 group. Additionally, the control group (PPL0) had the highest (p < 0.05) blood urea nitrogen (BUN), total cholesterol (TCHO) and low‐density lipoprotein cholesterol (LDLC) content compared with the groups supplemented with PPL. The PPL30 group had the highest (p < 0.05) triiodothyronine (T₃) and tetraiodothyroxine (T₄) value among the dietary groups.