Changes in technical efficiency of the broiler production in Poland, 1994–2013

1. The effects of changes in technical efficiency on the increase of broiler production are presented for the period 1994–2013 based on the panel data from seven farms located in southern and central Poland. A total of 766 cycles were analysed.

2. The Cobb–Douglas production function was used to assess the changes of output elasticities as well as technical changes in broiler production, for 5-year sub-periods separately.

3. Technical indices of broiler production significantly improved between years 1994–2013: feed conversion ratio decreased from 2.50 kg/kg to 1.78 kg/kg, mortality rate from 8.8% to 4.0% and daily weight gain increased from 37.1 g/d to 58.7 g/d, respectively.

4. Before accession to the EU, there was a substantial increase of fixed capital connected with modernisation of buildings and equipment. In the period 1994–2013, inputs of fixed capital per kilogram of livestock increased by 72% and at the same time the input of labour decreased by 56%.

5. Technical changes in years 1994–1998 contributed to a rapid production increase at a rate of 4.6% annually and only by up to 0.7% annually during 2009–2013. The slowdown of production rate increase after 2009 was partially caused by decreasing the stocking density.     

Antibody response to sheep erythrocytes in Indian native vis-à-vis imported breeds of chickens.

1. A total of 433 birds (7 weeks old) of both sexes belonging to Indian native breeds, including, Aseel, Kadakanath, Naked Neck and Frizzle fowl along with the imported breeds Dahlem Red, White Leghorn, Synthetic dam line broiler (SDL) and Naked Neck broiler were utilised to test the primary antibody response to sheep erythrocytes by haemagglutination test. The effect of genotype (breed), sex and their interactions on antibody response were also studied. 2. The results revealed the presence of natural antibodies in all groups under study. 3. All groups except broilers showed the highest HA titre on day 5 post immunisation, which gradually declined until the end of the experiment (19th day post immunisation). In broilers, the peak HA titre was observed on day 12. 4. Dahlem Red showed the highest response throughout. The lowest antibody response was recorded for broilers except on day 19 post immunisation when it exceeded the White Leghorn value. 5. Amongst the native Indian breeds, the Naked neck had the highest titre on day 5 post immunisation but the Aseel titre was highest on days 12 and 19. 6. Males tended to have higher titres than females in Aseel, Kadakanath, Naked Neck, White Leghorn and Naked Neck broilers whereas Frizzle, Dahlem Red and SDL broilers showed the converse. 7. Statistical analysis revealed significant variation in HA response among the various genetic groups on different days post immunisation. The apparent differences between sexes were not significant. However, interactions between breed and sex were significant on day 5 and 19 post immunisation.     

Ovarian morphology and internal vis-à-vis non internal laying in relation to triacylglycerol,hormones and their receptors concentration around the age of sexual maturity in broiler breeder hens

1. Ovarian morphology, serum hormone concentrations of 17-β-estradiol, progesterone, testosterone, tri-iodothyronine (T3), thyroxine (T4) and triacylglycerol (TAG) were investigated at 23 and 26 weeks of age in broiler breeder hens provided with ad libitum access to feed. Progesterone, oestrogen-β, thyroid-α and -β receptor mRNAs were also quantified in the infundibulum at the same ages.

2. A large variation in the ovarian morphology was observed at 23 weeks of age including hens with undeveloped ovaries, non-laying hens with post ovulatory follicles (POF) and a predominance of non-laying hens without a POF.

3. Serum concentrations of triglyceride, 17-β-estradiol and progesterone at 23 weeks of age were lower in hens with an undeveloped ovary compared with other groups of hens, whereas testosterone, triiodothyronine and thyroxin were higher.

4. At 26 weeks of age, the average number of hierarchical yellow follicles in normal layers was 7.64?±?0·41 whereas in internal layers, the follicular numbers were significantly greater at 8.66?±?0·53. The higher follicular numbers in internal layers were associated with higher serum triglyceride and progesterone concentrations.

5. Oestrogen receptor-β and thyroid receptor-β mRNA was up regulated in the infundibulum of internal layers compared with normal laying hens at 26 weeks of age.     

The use of air‐coolers in broiler houses under subtropical conditions in Iraq

1. Under summer conditions in north Iraq, 2 000 chicks were reared for 56 d in two broiler houses. One house was provided with two air‐coolers. The birds were housed at densities of eight to 16 birds/m².

2. Differences in weight gain between birds in cooled and uncooled houses ranged from 101.5 g at eight birds/m² to 385 g at 16 birds/m². Food consumption increased gradually with increasing bird density. Food conversion efficiency, meat yield and carcass conformation were much better in the cooled house than under conventional conditions.

3. The financial return/m² ranged from 2.30 to 4.51 ID¹ in the cooled house, compared with 2.01 to 2.77 ID in the uncooled house at different floor densities.     

The influence of nitrogen and defoliation on production and water‐use efficiency of Lolium multiflorum cv. Midmar

Abstract

The objective of this study was to investigate the influence of different nitrogen fertiliser application levels in combination with different defoliation intervals on the dry matter (DM) production and water‐use efficiency of ryegrass (Lolium multiflorum,) cv. Midmar. In a field trial, four nitrogen levels (0, 150, 300 and 450 kg N ha^?1) were combined with five defoliation intervals (every 2, 4, 6 and 8 weeks and twice a season). Soil moisture levels were measured with a neutron hydroprobe and were used to schedule irrigation. The dry matter production, nitrogen‐use efficiency (NUE), plant DM content and water‐use efficiency were influenced (P<0.01) by nitrogen level, defoliation interval, and the interaction between these factors. Total DM production varied from 64 to 20 922 kg DM ha^?1. Dry matter production per unit of applied N decreased with an increase in N level within a defoliation interval. The plant DM content varied from 14.0% to 35.6%. The plant DM content decreased (P<0.05) with increasing N applications, while a lengthening of the defoliation interval resulted in an increase (P<0.05) in the DM content. No difference (P>0.05) was found in total water used when plants received N. Water‐use efficiency varied from 1.2 to 25.8 kg DM ha^?1 mm^?1 water received.     

Impact of a Mastitis control program in Valdres,Norway, during 1982–1985

The present study examined the effect of the mastitis control program (MCP) on milk production, incidence of mastitis, incidence of teat lesions, culling, log₁₀ of the bulk tank milk somatic cell count (LBMSC) and economic returns in Valdres, Norway, during 1982–1985. The major economic impact of the MCP was due to improved milk quality and to a lesser degree due to increased milk production. This might be explained by the Norwegian policy aimed at reducing the milk surplus through production quotas. The net present value of MCP, using a 15% discount rate, for an average 12-cow herd was 5599-3372 Nkr ($800-482) for production within or above the milk production quota, respectively. Since the program was provided free of charge to the individual farmer, this was also the net benefit to the MCP-participating farmer.     

How do resources influence control measures during a simulated outbreak of foot and mouth disease in Australia?

An outbreak of foot and mouth disease (FMD) could seriously impact Australia's livestock sector and economy. As an FMD-free country, an outbreak would trigger a major disease control and eradication program that would include the culling of infected and at risk animals (‘stamping out’), movement restrictions and zoo-sanitary measures. Additional control measures may also include pre-emptive culling or vaccination. However, it is unclear what disease strategy would be most effective under Australian conditions and different resource levels. Using a stochastic simulation model that describes FMD transmission between farms in a livestock dense region of Australia, our results suggest that using current estimates of human resource capacity for surveillance, infected premises operations and vaccination, outbreaks were effectively controlled under a stamping out strategy. However, under more constrained resource allocations, ring vaccination was more likely to achieve eradication faster than stamping out or pre-emptive culling strategies.     

Diurnal‐nocturnal changes in food intake,gut storage of ingesta,food transit time and metabolism in growing broiler chickens: A model for temporal control of energy balance

1. Diurnal—nocturnal changes in food intake, gut storage of ingesta, food transit time and heat production were studied in male broiler chickens reared under a 14L:10D lighting schedule (lights on from 06.00 to 20.00 h).

2. Food consumption during the scotophase was negligible. Peak food consumption during the photoperiod occurred at the beginning of the photoperiod and in the late afternoon.

3. During the photoperiod, the crop and proventriculus/gizzard contained only small quantities of ingesta. However, at the beginning of the scotoperiod, dried ingesta content of crop and proventriculus/gizzard increased by 10.5‐ and 2.76‐fold respectively. This increase was followed by a gradual decrease towards the end of the scotoperiod.

4. Food transit time during the scotoperiod was significantly longer than that during the photoperiod.

5. The daily pattern of heat production closely followed the 14L:10D lighting schedule. Total heat production during darkness averaged 53% of total heat production during the photoperiod.

6. It was estimated that the storage of energy (as ingesta) in the crop and proventriculus/gizzard, followed by its gradual release and the increased food transit time during the night, contributed 75.5% of nocturnal energy needs. It must be recognised that these mechanisms play a major role in the energy balance of the growing chicken during periods without food intake.     

Performance of a new carbon dioxide absorbent,Yabashi lime? as compared to conventional carbon dioxide absorbent during sevoflurane anesthesia in dogs

In the present study, we compare a new carbon dioxide (CO₂) absorbent, Yabashi lime^® with a conventional CO₂ absorbent, Sodasorb^® as a control CO₂ absorbent for Compound A (CA) and Carbon monoxide (CO) productions. Four dogs were anesthetized with sevoflurane. Each dog was anesthetized with four preparations, Yabashi lime^® with high or low-flow rate of oxygen and control CO₂ absorbent with high or low-flow rate. CA and CO concentrations in the anesthetic circuit, canister temperature and carbooxyhemoglobin (COHb) concentration in the blood were measured. Yabashi lime^® did not produce CA. Control CO₂ absorbent generated CA, and its concentration was significantly higher in low-flow rate than a high-flow rate. CO was generated only in low-flow rate groups, but there was no significance between Yabashi lime^® groups and control CO₂ absorbent groups. However, the CO concentration in the circuit could not be detected (≤5ppm), and no change was found in COHb level. Canister temperature was significantly higher in low-flow rate groups than high-flow rate groups. Furthermore, in low-flow rate groups, the lower layer of canister temperature in control CO₂ absorbent group was significantly higher than Yabashi lime^® group. CA and CO productions are thought to be related to the composition of CO₂ absorbent, flow rate and canister temperature. Though CO concentration is equal, it might be safer to use Yabashi lime^® with sevoflurane anesthesia in dogs than conventional CO₂ absorbent at the point of CA production.     

Changes in egg quality traits during the last phase of production: is there potential for an extended laying cycle?

1. A field study was conducted to investigate the deterioration of eggshell quality at the end of lay and examine the potential to extend the production cycle. A total of 1200 eggs were assessed originating from commercial farms in Belgium: eggs were random sampled at the collection belt at 57–65 weeks of age and at the end of the production cycle (74–92 weeks).

2. Based on a linear mixed model, egg quality was estimated for an average flock at 60 weeks of age and changes in quality traits were predicted until the end of the laying cycle.

3. Egg weight increased by 0.07 g every week from 60 weeks of age onwards and shape index decreased by 0.04 unit weekly (P < 0.001). Haugh unit values decreased weekly by 0.38 units whereas relative yolk weight was unaffected after 60 weeks of age. Relative albumen weight showed a weekly increase of 0.02% and relative shell decreased by 0.02% weekly until the end of lay.

4. Shell quality traits were also influenced by age: shell index decreased by 0.013 g weekly, shell thickness was calculated to be 0.23 µm thinner every week, deformation increased by 0.06 µm weekly from 60 weeks to the end of the laying cycle. Variability of the deformation of eggs indicated more heterogeneous shell quality at the end of the production cycle. Dynamic stiffness increased from 60 weeks of age on.

5. Laying hens were depopulated on average at 80 weeks of age (varying from 74–92 weeks). Although ageing had a significant effect on most of the egg quality traits, egg quality was still acceptable at the end of lay, indicating the potential to extend the laying cycle.