The studies of efficacy and safety of doxycycline powder hyclatin colibaciloză in broilers

Aim of the study

It is proposed to assess therapeutic efficacy and safety of a tetracycline antibiotic family that is a soluble powder for hyclat of doxycycline administration in drinking water for birds.

Objective

Evaluation of therapeutic effect on broiler in an outbreak of colisepticemie.

MATERIALS AND METHODS

Presentation:

Hyclatul doxycycline is a structural isomer of reference which meets European standards (Ph.Eur. III 1997:0272) and comply with Council regulation EEC (No 2377/90), on M.R.L. (Maximum residue limits) published in O.J.E.C. (Official Journal of the European Communities) (4.13).

Like all family representatives tetracycline doxicilina is an inhibitor of protein synthesis in susceptible microorganisms. She crosses directly through the bacterial wall membrane bilipidica broad-spectrum antibiotic effective in the majority of infections caused by gram-positive and Gram-negative bacteria, mycoplasma, frequently isolated from birds, riketsii, chlamidii and some protozoa. (1,7,14).

Metal ions, most often those of iron significantly decreases the effectiveness of the active substance subsequent oral administration through the formation of insoluble complexes (chelates iron).

Good solubility, allowing the active substance to be highly absorbed and distributed in tissues and organs via administration of water.

Presentation of compliance:

Yellow powder, crystalline, hygroscopic. In the recommended levels of 100 ml / liter water, the powder is easily soluble in drinking water, and dissolve in alkaline hydroxides and carbonates.

Composition of the test product:

Hyclat doxycycline 0.3 g

Excipients q.s. ad 1.0 g.

Target animals:

broilers, turkeys.

Dosage: General dose is 10 mg doxycycline / kg bodyweight.

BroilersAge

Week

The weight of100 animals (kg)

Water consumptionin three hours (liter)

Quantityof substance (g)

1 140 3,75 5,0

2 300 7,5 10,0

3 570 11,25 20,0

4 880 15 30,0

5 1200 18,75 40,0

6 1600 22,5 55,0

7 1940 27,5 65,0

Adults 3000 37,5 100,0

Turkey4 1000 15 35

8 3000 32,5 100

16 11000 65 370

24 17000 90 570

Adults 25000 112,5 830

Usage: For broilers and turkeys: 10 mg / kg bodyweight in drinking water for 3-5 days. Before treatment the animals are deprived of water retention, introducing the fluid diet. The medicine is diluted in a quantity of water required for 3 o'clock. In calculating the amount of water necessary will consider ambient temperature, and higher body temperature of animals.

Frequency of use:

In poultry frequency of administration is highly dependent on the growth period of species (approximately 40 days in broilers, turkeys and 120-150 days to 420-450 days for laying hens).

If preventive treatment is almost continuous exposure while exposure curative treatment is phasic. Taking into account the mode and route of administration of doxycycline hyclatului

powder is recommended daily for 3-5 days, considered the contact period, followed by a contact indirectly through contact with urine or faeces during the depletion of tetracycline ( Estimated duration to a maximum 12 days).

For repeated treatments the frequency of administration is 7-10 days. In the worst case, according to the above, that we have a potential exposure to 16.875mg doxycycline 1350 kg (per 1000 broiler) that is 17g. of tetracycline in 1000 broiler (34g if the treatment is repeated) and 187,500 mg doxycycline (tetracycline 187g) at 1,000 turkeys to the total weight of 15,000 kilograms.

Contraindications: Do not use at once with other antibiotics.

Standby Time: in broilers = 7 days, turkey = 10 days

Warnings: not used for the treatment of laying hens!

Research Methodology:

- Identifying cases of disease and setting lots.

- Sampling to determine etiologic diagnosis.

- Making antibiogram whit difuziometric method.

- Administration of standardized product after the recommended by the manufacturer.

- Monitoring the clinical course after treatment (Experiment 1)

- Tracking trends in weight gain.

The animals:

The product has been clinically tested on broilers, hybrids Cobb, a farm town of 3,000 heads of Lugojel, Timis county, in which offspring rearing on the ground.

Epidemiological investigation revealed the presence of factors favoring the firm, because of deficiencies combined zooigienă: moisture supraaglomeraţie, variations of temperature in thermal comfort.

Under these conditions there were frequent episodes of enteric, lack of appetite and polydipsia, which were identified to be colisepticemie.

The disease started at the age of 20 days to chickens, and the mortality rate reached at 32.5%. The disease was confirmed by pathologoanatomic and bacteriological examination.

Health and bio-parameters were followed by:

- clinical examination: the assessment of appetite, temperature, specific consumption (feed and water), mobility, enteric and respiratory signs.

- morphopathological: necropsy of all the dead chickens and picture viewing feature.

- economic: the rate of feed consumption and average daily growth rate achieved after treatment was recorded by weighing on the lot of 20 and 30, 40 and 50.

The hall was built by a speaker 4 x 5 m, which were randomly placed 120 chickens, all with clinical evidence of colisepticemie. It also set up a batch of 12 chickens that were the control group in which no treatment was applied only to monitor the clinical course.

The maintenance system was ground type semiintesiv, disinfect the place, equipped with heating lamps, friendly pup growth during the period of monitoring.

The feeding chickens was ad libitum in nourishing the soil, with mixed fodder under age category, with concentrated feed broiler starter CC 1115 (Vivabio) balanced quality.

Watering was done at the discretion of plastic adapters.

Methods:

The presence of disease, and frequency of cases was established by bacteriological and pathological examination.

Bacteriological examinations were carried out revealed the presence of numerous strains of Escherichia coli (11 strains).

Bacterial strains isolated were tested against the behavior of antibiotics in antibiogram (set Sanofi) was used to microcomprimate: Colistin sulfate, Neomycin, Amoxiklav, Enrofloxacin, norfloxacin, erythromycin, spectinomycin and doxycycline.

The proportion of strains resistant to multiple antibiotics was variable, showing high efficacy Colistin sulphate but all isolates of E. coli were very sensitive and Doxycycline.

Dosage:

Doxiphyl SP 100% A.U.V. according to the manufacturer's recommended drinking water in daily therapeutic dose of 10 mg / kg bw for 3-5 days.

In practice, this means the application of powder 100 mg / l drinking water.

Medicated water should be consumed within three hours after administration, for which diet is recommended fluid two hours before treatment.

In our case, the drug was given for 5 days in the batch of chicken, aiming at: the dynamics of mortality and clinical developments in the days of treatment and again five days after it.

RESULTS AND DISCUSSION

Analyzing the evolution of mortality was observed on the first day, ie before the first administration, this indicator had a value quite close (14.2%) of mortality existing in the hall.

On the second and third days after dosing, mortality levels have maintained high values but with a decreasing trend (from 8.3% to 5.9%).

In the coming days, mortality levels declined significantly in the days of the fourth and fifth respectively, the last day of treatment, the recorded as low as 2.5% and 1.7%.

Mortality were recorded and on the sixth day after the treatment period but recorded values were low (0.8%).

In the days of the seventh, eighth, ninth and tenth of the study have not registered mortality in chickens.

Favorable clinical course were recorded after the third day of treatment, (the seventh day mortality halting), at the end of treatment remained alive 80 chicken, (ie 66.7% of the total) with the general condition improved and after 5 days of treatment the clinical signs have disappeared entirely.

Following situation control group found the death of all untreated chickens until the fourth day.

The good results obtained confirm the therapeutic efficacy of the product in an outbreak of disease, although the losses recorded, confirming the results of clinical testing antibiogramelor.

The bodies, the duration of the experiment were necropsiate being emphasized all known lesions characteristic colisepticemiei: hypertrophy of the spleen, bleeding, perihepatită, pericarditis, aerosaculită fibrin, serious and irreversible (8).

Although doxycycline was effective, irreversible damage leading to death colisepticemie installed chickens. This explains why mortality remained relatively high during the first three days of treatment.

It should be noted that batch of chickens undergoing therapy with doxycycline hyclat was formed only in young patients with symptoms in different evolutionary stages of sepsis colibaciloză

Of course, as is known, chicks with advanced forms of disease could not be recovered even if the drug administered was effective bacteriological (8). This was confirmed by the results of bacteriological examination, the bodies of chickens undergoing treatment we isolated strains of E. coli.

In the coming days mortality was significantly reduced, the result of bacteriological tests were negative. Evolution losses colisepticemie chicken is reproduced in Figure 1.

Fig. 1. Evolution losses studied group

After the treatment, the clinical and the biological recovery of the chickens was good, as evidenced by the evolution of weight gain in young survivors, who were weighed until slaughter (day 20, 30, 40 and 50).The values of weight gain and specific consumption of chicken treated group were within the parameters of the hybrid productive from the day that the 30th onwards (6).

Table 3.Average daily growth rate, average daily feed consumption and average daily water

consumption expressed in period

The lot on the day

Weight

Lot

WeightMedium

Term average daily gain (g)

Average daily feed

consumption (g)

Average consumptionWater (ml)

Day 20

120capete73800 g 655 g 30,75 56 ( 6,5 kg) 200

Day 30

40 loss75280 g 941 g 24,60 110 (8,80 kg) 300

Day 40

80 remaining

119600 1495 g 51,40 170 (13,60 kg) 370

Day 50 174400 2180 68,50 190 (15,20 kg) 450

17

14,2

10

8,3

7

5,9

3

2,5

2

1,7

10,8

0 0 0 0

0

5

10

15

20

25

30

35

% 14,2 8,3 5,9 2,5 1,7 0,8 0 0 0 0

Dead chicken17 10 7 3 2 1 0 0 0 0

I II III IV V VI VII VIII IX X

Slaughter

CONCLUSIONS

The Doxiphyl SP Product in dose of 20 mg / perkg of bodyweight., Administered for five days resulted in complete clinical cure and bacteriological broiler with colisepticemie and recovery after therapeutic.

Therapy is preferable even if the economic assessment parameters are significantly lower disease-free situations.

After treatment, clinical and biological recovery of the chickens was good, as evidenced by the evolution of weight gain in chickens remaining.