Effect of setting a maximum milking time,from peak lactation,on production,milking time and udder health

Abstract

AIM: To examine the effect of setting a maximum milking time, from peak lactation until drying-off, on production, duration of milking, and udder health of dairy cows.

METHODS: Forty cows were assigned in twin-pairs to be either milked until cups were removed at a milk flow-rate threshold of 0.35 kg/minute (Control), or until cups were removed at a milk flow-rate threshold of 0.35 kg/minute, or maximum time, whichever came first (MaxT). The maximum time was set by determining the milking time of the 70th percentile cow when ranked from fastest to slowest, irrespective of yield. The milking routine was typical of that practised on dairy farms in New Zealand, and involved no pre-milking preparation. The study began at peak lactation (68 (SD 7) days in milk; DIM) and continued for 26 weeks. Duration of milking and milk yield were measured for each milking. Composition of milk was determined from weekly herd tests, and milk quality from fortnightly somatic cell counts (SCC). Completeness of milking and teat condition were assessed during the study. The bacterial status of quarter milk samples was determined at the beginning and end of the study, and all treated cases of clinical mastitis recorded. ANOVA was used to examine the effect of treatment group on variables of interest.

RESULTS: Total milk, fat and protein yields during the study period did not differ between treatments. On average, 30.3% of the morning and 27.6% of the afternoon milkings of MaxT cows reached the maximum time at which cups were removed, and were therefore shortened. While the average milking time of the slowest-milking cow was longer for the Control compared with MaxT group in Weeks 1–18, the average milking time did not differ between treatments. There was no difference in overall SCC, and the incidence of clinical mastitis, or the percentage of infected quarters at drying-off, was similar for the MaxT and Control cows.

CONCLUSION: The results show that setting a maximum milking time can reduce the milking time of slower-milking cows in a herd without compromising overall herd production and udder health.

CLINICAL RELEVANCE: Although the numbers of cows in the study were small there was no evidence of a major increase in SCC, or subclinical or clinical mastitis when a maximum milking time was set for slower-milking cows.     

A new record of Rhizoctonia butinii associated with Picea glauca ‘Conica’ in Slovenia

In 2013, the death of needles of dwarf Alberta spruce (Picea glauca ‘Conica’) seedlings was observed in an arboretum in Slovenia. Needles on infected P. glauca ‘Conica’ twigs were covered with thick, yellowish brown hyphal cushions. The outgrowing mycelium was white and had completely overgrown some needles and connected them to each other. To definitively identify the fungus affecting P. glauca ‘Conica’, morphological examinations of isolated pure cultures were performed, and the internal transcribed spacer (ITS) region of the rDNA was sequenced. Based on morphological and molecular phylogenetic analyses together with the performed pathogenicity trial, we identified the causal agent of the observed symptoms as Rhizoctonia butinii – a recently described species. This report connects this fungus to a new locality and a new host plant.     

Demodicosis in nine prairie dogs (Cynomys ludovicianus)

This case report describes the clinical signs and treatment of demodicosis in nine pet prairie dogs (Cynomys ludovicianus). Clinical records including history, clinical examination, microscopic evaluation and fungal culture of the skin lesions were available for all nine animals. In seven animals, blood was obtained for haematological and biochemical analyses. Clinical signs comprised bilaterally symmetrical alopecia extending from the middle part of the back down to the skin of the thighs and the dorsal and ventral parts of the tail. Demodex mites were found in skin scrapings from all cases. Treatment with amitraz at 250 p.p.m. resulted in resolution of lesions and hair regrowth. This is the first report of demodicosis in this species.     

Impact of a high-phosphorus diet on the sonographic and CT appearance of kidneys in degus, and possible concurrence with dental problems

The main aim of this study was to investigate the impact of pelleted diet of different mineral composition on the sonographic and CT appearance of kidneys in degus (Octodon degus). A total of 35 animals were randomly divided into five groups, fed diets containing different calcium and phosphorus contents (13.5 g/kg calcium and 6.3 g/kg phosphorus, or 9.1 g/kg calcium and 9.5 g/kg phosphorus) and given different amounts of exposure to UV light. Endoscopic examination of the oral cavity as well as renal ultrasonography and CT was performed four times at four-month intervals throughout the study. After 14 months of feeding an experimental diet, all degus were euthanased and subsequently all kidneys were collected for histopathological examination. Animals fed a diet with high dietary phosphate and improper calcium to phosphorus ratio showed severe nephrocalcinosis. Ultrasonographic and CT kidney abnormalities presented as hyperechogenicity and hyperdensity (interpreted as nephrocalcinosis), respectively. The most striking changes were seen at the corticomedullary zone. Ultrasonography and CT correlated in all cases with histopathological findings. Dental disease developed quickly in groups fed diets with an improper calcium and phosphorus content, with obvious apical and coronal elongation of all the teeth. A possible influence of UV light access could not be proved in this study.     

Toll‐like receptor and related cytokine mRNA expression in bovine corpora lutea during the oestrous cycle and pregnancy

Improving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll‐like receptors (TLR) mediate innate immune mechanisms via the production of pro‐inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30–50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll‐like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN‐G), and interleukin (IL)‐12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL‐6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro‐inflammatory cytokine mRNA expression.     

Strong regularities in world wide web surfing

One of the most common modes of accessing information in the World Wide Web is surfing from one document to another along hyperlinks. Several large empirical studies have revealed common patterns of surfing behavior. A model that assumes that users make a sequence of decisions to proceed to another page, continuing as long as the value of the current page exceeds some threshold, yields the probability distribution for the number of pages that a user visits within a given Web site. This model was verified by comparing its predictions with detailed measurements of surfing patterns. The model also explains the observed Zipf-like distributions in page hits observed at Web sites.     

广东省坡地柑桔园有机无机肥料配施的效应研究

在赤红壤发育的旱坡地柑桔园开展不同有机无机肥料配施肥效试验,结果表明,与单施化肥相比,有机肥配施化肥能显著提高柑桔的产量和食用品质,其中沙糖桔增产率为16.3%～18.4%,年桔增产率为7.8%～16.4%。此外,施用有机肥处理能显著提高柑桔园土壤微生物量,在施用等氮量条件下,随着有机肥施用量的增加土壤微生物量碳和氮呈递增趋势,说明施用有机肥对柑桔园土壤微生物量碳和氮有显著的影响。     

Infestation in the dog by the paralysis tick, Ixodes holocyclus — 5. Treatment

In this study the value of drugs administered with hyperimmune serum in the treatment of advanced disease produced by Ixodes holocyclus was compared under controlled conditions. All control dogs died rapidly whereas one dog survived and 3 dogs died after receiving hyperimmune serum alone. When promethazine hydrochloride was administered with hyperimmune serum 2 dogs recovered rapidly while the remaining 2 died. Administration of dexamethasone and hyperimmune serum allowed 3 dogs to survive while administration of phenoxybenzamine hydrochloride in conjunction with hyperimmune serum allowed rapid recovery of all 4 dogs. Phenoxybenzamine hydrochloride, an alpha-adrenergic blocking drug, was chosen because of its potential to attenuate the arterial hypertension previously reported (Ilkiw et al 1988). The survival of all dogs together with the rapid return to normality indicated that this drug was beneficial in the treatment of dogs with advanced signs of tick paralysis.     

Pharmacokinetic evaluation of enrofloxacin administered orally to healthy dogs.

Enrofloxacin was administered orally to 6 healthy dogs at dosages of approximately 2.75, 5.5, and 11 mg/kg of body weight, every 12 hours for 4 days, with a 4-week interval between dosage regimens. Serum and tissue cage fluid (TCF) concentrations of enrofloxacin were measured after the first and seventh treatments. The mean peak serum concentration occurred between 1 and 2.5 hours after dosing. Peak serum concentrations increased with increases in dosage. For each dosage regimen, there was an accumulation of enrofloxacin between the first and seventh treatment, as demonstrated by a significant (P = 0.001) increase in peak serum concentrations. The serum elimination half-life increased from 3.39 hours for the 2.75 mg/kg dosage to 4.94 hours for the 11 mg/kg dosage. Enrofloxacin accumulated slowly into TCF, with peak concentrations being approximately 58% of those of serum. The time of peak TCF concentrations occurred between 3.8 hours and 5.9 hours after drug administration, depending on the dosage and whether it was after single or multiple administrations. Compared with serum concentrations (area under the curve TCF/area under the curve serum), the percentage of enrofloxacin penetration into TCF was 85% at a dosage of 2.75 mg/kg, 83% at a dosage of 5.5 mg/kg, and 88% at a dosage of 11 mg/kg. All 3 dosage regimens of enrofloxacin induced continuous serum and TCF concentrations greater than the minimal concentration required to inhibit 90% (MIC90) of the aerobic and facultative anaerobic clinical isolates tested, except Pseudomonas aeruginosa.(ABSTRACT TRUNCATED AT 250 WORDS)