Does the Amount of Progesterone in Intravaginal Implants Used to Synchronise Oestrus Affect the Reproductive Performance of Brahman Heifers Artificially Inseminated at a Fixed Time

The study tested the hypothesis that reduced intravaginal implant progesterone (P₄) concentration to synchronise oestrus would increase pregnancy rates to fixed‐time artificial insemination (FTAI) in Bos indicus heifers. Brahman heifers (n = 294; 2 year) were body condition scored (BCS), weighed and scanned for presence of a corpus luteum (CL). Only cyclic heifers were selected and allocated randomly within BCS and 25 kg bodyweight category to one of three P₄ treatment groups. On day 10, heifers received a P₄ implant (CueMate‐1‐pod, 0.78g P₄; CueMate‐2‐pod, 1.56g P₄; or CIDR‐B, 1.9g P₄), 2 mg oestradiol benzoate (ODB) intramuscularly (IM) and 250 ug cloprostenol IM. At day 2, the implant was removed, 250 ug cloprostenol was injected IM and tail paint applied. The heifers received 1 mg ODB 24 h later and were FTAI 48–54 h after implant removal (day 0). Ten randomly selected heifers per group were blood sampled and scanned at days 10, 2, 0 and 6 to define the P₄ profiles pre‐ and post‐FTAI. Heifers were heat‐detected 18–20 days post‐FTAI and oestrous heifers AI’d by the AM/PM rule. Bulls joined the heifers on day 27 post‐FTAI. Transrectal ultrasonography estimated conception date on day 72. Statistical analysis examined the effects of treatment, technician, semen, ovarian status, BCS and liveweight, on pregnancy rate (PR) to FTAI. There was no significant difference (p = 0.362) in PR between treatment groups (CueMate 1‐pod, 36.4%; CueMate 2‐pod, 39.6%: CIDR‐B, 28.3%), but PR was higher in those heifers with increased BCS between FTAI and pregnancy diagnosis (p = 0.005). Thirty‐three per cent of monitor heifers had plasma P₄ concentrations of <1 ng/ml on day 6 after FTAI; only 20% of these conceived vs 60% of heifers with P₄ ≥ 1 ng/ml. In summary, no significant difference in PR was identified between treatments but good BCS and a rising plane of nutrition were critical to PR of these pure grade Brahman heifers in northern Australia.     

The Effect of Oxidative Stress on Thawed Bulk‐Sorted Red Deer Sperm

The aims of this study were to assess the effects of the sex‐sorting process on post‐thaw sperm quality as well as on induced oxidative stress damage (H₂O₂ 0 mm  = H000; H₂O₂ 50 mm  = H050; H₂O₂ 100 mm  = H100) and the protective action of reduced glutathione (GSH) and Trolox, when comparing sorted (BSS) and non‐sorted (NS) red deer spermatozoa incubated at 37°C. Sperm samples from three stags were collected by electroejaculation and frozen. Immediately after thawing, sperm motility was higher (p < 0.05) for NS (59% ± 3.3) than BSS (36.9% ± 5.8) sperm. Furthermore, the percentage of apoptotic sperm was higher (p < 0.05) for BSS (21.6% ± 5.0) than NS sperm (14.6% ± 1.2). The presence of H₂O₂ increased DNA damage in NS (H000 = 4.1% ± 0.9; H050 = 9.3% ± 0.7; and H100 = 10.9% ± 2.3), but not in BSS sperm. However, in the presence of oxidant, GSH addition improved (p < 0.05) sperm motility in both groups of sperm samples as compared to their controls (NS: 44.5 ± 4.8 vs 21.1 ± 3.9 and BSS: 33.3 ± 8.1 vs 8.9 ± 1.8). These results demonstrate that the sperm‐sorting process induces sublethal effects, albeit selecting a sperm population with a chromatin more resistant to oxidative stress than that in non‐sorted sperm. Moreover, addition of GSH at 1 mm may be a good choice for maintaining the quality of stressed sperm samples, unlike Trolox, which inhibited sperm motility.     

Selection of red deer spermatozoa with different cryoresistance using density gradients

The objective of sperm selection media is selecting the best spermatozoa and to remove seminal plasma and diluent for using them in assisted reproductive techniques. It is known that individuals show different cryoresistance in response to the same freezing procedure. Our hypothesis was that the efficacy of selection media could be dissimilar for samples with different sperm quality after thawing. Epididymal sperm samples from mature Iberian red deer were collected and frozen. Males were classified as with high post‐thaw sperm quality when sperm motility (SM) ≥ 70%, or as with low post‐thaw sperm quality when SM ≤ 69%. Samples were centrifuged using the following density gradients (DG): Percoll^®, Puresperm^® and Bovipure^?, and several functional sperm parameters were assessed after sperm selecting and washing. Males classified with high sperm quality had higher post‐thawing values (p > .05) for all parameters evaluated, except for linearity index, than those categorized as low sperm quality. After selection, some sperm characteristics improved (viability, apoptosis and mitochondrial activity) for both groups, showing the males with high sperm quality higher values in all sperm parameters except for kinematic traits and DNA fragmentation index (%DFI), regardless of DG. Bovipure^? yield lower values of sperm motility, viability, apoptosis and mitochondrial activity in relation to Percoll^® and Puresperm^® considering both quality groups. There was an interaction between the type of DG and sperm quality group for sperm viability (p = .040) and apoptosis (p = .003). Thus, Percoll^® selected less live and more apoptotic spermatozoa than Puresperm^® and Bovipure^? for males with low sperm quality. In conclusion, the DG are more efficient selecting spermatozoa from samples with high sperm quality, acting differently depending on initial sperm quality.     

Bioassay-guided isolation of vasorelaxant compounds from Ziziphora clinopodioides Lam. (Lamiaceae)

Ziziphora clinopodioides Lam. (Lamiaceae) is traditionally used in Uighur's medicine for the treatment of hypertension. Our study determined and evaluated the bioactive compounds by performing an activity-guided fractionation of a hydroalcoholic extract of the whole plant, using an in vitro model of rat isolated thoracic aortic rings. Seven compounds were identified as active principles: acacetin, apigenin, chrysin, thymonin, acetovanillone, 4-hydroxyacetophenone and ethyl 4-coumarate. Apigenin, chrysin and ethyl 4-coumarate were found to be the most effective. Our results provide the first evidence that the vasodilation induced by Z. clinopodioides Lam. is mediated, at least in part, by phenolic components.     

Contribution of participatory forest management towards conservation and rehabilitation of dry Afromontane forests and its implications for carbon management in the tropical Southeastern Highlands of Ethiopia

Participatory forest management (PFM) has been applied as an approach to create a framework for collaborative forest management between local communities and government forestry agencies. This study was designed to assess the contribution of PFM approach in improving forest status in the Southeastern Highlands of Ethiopia. Landsat satellite imageries of four years were used to evaluate the trends and rate of deforestation before and after PFM interventions. Socio-economic data were collected from sample household surveys, key participants, focus group discussions, and field observations. The results showed that there was high rate of deforestation before PFM intervention as forestland has decreased by 19% (2531 ha) between 1990 and 2000. However, after the PFM intervention (2000–2016), the forest cover has increased by 247 ha (2.2%). During this period, net 1016 ha of shrub-lands were converted into forestland owing to significant forest regeneration. In addition, most sampled households (94% and 96% from lower and upper altitudes, respectively) perceived that PFM had significantly contributed to improve forest regeneration in their locality. This study revealed that PFM can serve as a stepping stone for carbon financing mechanisms to reduce greenhouses emission and enhance carbon sinks via forest resources.     

Tetravalent uranium in calcite

X-ray absorption spectroscopy and x-ray fluorescence microprobe studies of 35-million-year-old calcite from a Mississippi Valley-type zinc ore deposit indicate substitution of tetravalent uranium for divalent calcium. Thus, tetravalent uranium has a stable location in calcite deposited under reducing conditions. This result validates uranium-series dating methods (including uranium/lead dating) for ancient calcite and shows that calcite provides a sink for uranium in deep groundwater aquifers and anoxic lacustrine and marine basins.     

Isolation and identification of bubaline herpesvirus 1 (BuHV-1) from latently infected water buffalo (Bubalus bubalis) from Iran

In order to isolate buffaloes herpesvirus 1 (BuHV-1) from latently infected water buffalo (Bubalus bubalis), 16 buffalo heifers were selected from a herd. At first, animals were bled and their sera were tested by virus neutralization (VN) test, using bovine herpesvirus 1 (BoHV-1). According to the results of VN test and dexamethasone injection (0.1 mg/kg BW) for 5 consecutive days, the examined buffaloes were divided into 4 groups. Vaginal and nasal swabs were daily collected from all buffaloes from day 0 to 10 days later. Based on the cytopathic effects in cell culture, a herpesvirus was isolated only from nasal swabs of three seropositive buffaloes which they had received dexamethasone. The nasal swabs of these three buffaloes were also positive in PCR, using primers specific for ruminant herpesviruses gD gene. The identity of the isolated viruses was determined according to partial amino acid sequences of gD, deduced from the nucleotide sequences of the PCR products. On the basis of sequence alignment, phylogenetic analysis, and genetic distances, the three buffalo virus isolates were more closely related to BuHV-1 and BoHV-5 than to BoHV-1.

     

Bryan William (Bill) Manktelow (20 February 1930 – 3 May 2003)

When Bill Manktelow died at his home in his 74th year on the 3rd of May, the veterinary profession lost a major figure whose work over 50 years has influenced many people in all branches of the profession.